Bodily changes in pain, hunger, fear and rage, an account of recent researches into the function of emotional excitement

/f/5

■>-

CORNELL

UNIVERSITY

LIBRARY

BOUGHT WITH THE INCOME
OF THE SAGE ENDOWMENT
FUND GIVEN IN 1891 BY

HENRY WILLIAMS SAGE

Datf» Ti\i^ —

DATE DUE

•

-

p*^

-

^-x^ 'Jh

'

'STT. V

-

1

B

-

„

.

CAYLORO

PRINTED(NU.S A.

Cornell University Library
QP 401.C22 1915

Bodily changes in pain hunger fear and

3 1924 022 542 470

,C

^

o/

Cornell University
Library

The original of tliis book is in
tlie Cornell University Library.

There are no known copyright restrictions in
the United States on the use of the text.

http://www.archive.org/details/cu31924022542470

BODILY CHANGES
IN PAIN, HUNGER,
FEAR AND RAGE

AN ACCOUNT OF RECENT RE-
SEARCHES INTO THE FUNCTION
OF EMOTIONAL EXCITEMENT

BY , •

WALTER B.' CANNON

GEOBGB HIGGINSON PROFESSOR OF PH78IOLOOT IN
HARVARD UNIVERSITY

NEW YORK AND LONDON
D. APPLETON AND COMPANY

1915

s

■ 1 h'. i;/;t;V

^

,^,^lgoG'i

Copyright, 1915, by
D. APPLETON AND COMPANY

Printed in the United States of America

TO MY COLLABORATORS IN THESE RESEARCHES

DANIEL DE LA PAZ
ALFRED T. SHOHL
WADE S. WEIGHT
ARTHUR L. WASHBURN
HENRY LYMAN
LEONARD B. NICE
CHARLES M. GRUBER
HOWARD OSGOOD
HORACE GRAY
WALTER L. MENDENHALL

WITH PLEASANT MEMORIES OF OUR
WORK TOGETHER

PREFACE

Fear, rage and pain, and the pangs of hunger are all
primitive experiences which human beings share with
the lower animals. These experiences are properly classed \
as among the most powerful that determine the action
of ^ men and beasts. A knowledge of the conditions |
which attend these experiences, therefore, is of general
and fundamental importance in the interpretation of
behavior.

During the past four years there has been conducted,l\
in the Harvard Physiological Laboratory, a series of in-
vestigations concerned with the bodily changes which '
occur in conjunction with pain, hunger and the major
emotions. A group of remarkable alterations in the
bodily economy have been discovered, all of which can
reasonably be regarded as responses that are nicely
adapted to the individual's welfare and preservation.
Because these physiological adaptations are interesting
both in themselves and in their interpretation, not only
to physiologists and psychologists, but to others as well,
it has seemed worth while to gather together in con-
venient form the original accounts of the experiments,
which have been published in various American medical
and physiological journals. I have, however, attempted
to arrange the results and discussions in an orderly
and consecutive manner, and I have tried also to elim-

vii

viii PREFACE

inate or incidentally to explain the technical terms, so
that the exposition will be easily understood by any
intelligent reader even though not trained in the med-
lical sciences.

My first interest in the conditions attending pain,
hunger and strong emotional states was stimulated dur-
ing the course of a previous series of researches on the
imotor activities of the alimentary canal. A summary
of these researches appeared in 1911, under the title,
"The Mechanical Factors of Digestion." The studies
recorded in the present volume may be regarded as a
natural sequence of observations on the influence of
emotional states on the digestive process, which were
reported in that volume.

W. B. Cannon.

CONTENTS

CHAPTEE I

PAGES

THE EFFECT OF THE EMOTIONS ON DIGESTION

Emotions favorable to normal secretion of the digestive
juices — ^Emotions unfavorable to normal secretion of
the digestive juices — Emotions favorable and un-
favorable to contractions of the stomach and in-
testines — The disturbing effect of pain on di-
gestion 1-21

CHAPTEE II i/^

THE GENERAL ORGANIZATION OF THE VIS-
CERAL NERVES CONCERNED IN EMOTIONS

The outlying neurones — The three divisions of the out-
lying neurones — The extensive distribution of neu-
rones of the "sympathetic" or thoracico-lumbar di-
vision and their arrangement for diffuse action — The
arrangement of neurones of the cranial and sacral
divisions for specific action — The cranial division a
conserver of bodily resources — The sacral division
a group of mechanisms for emptying — The sympa-
thetic division antagonistic to both the cranial and
the sacral— Neurones of the sympathetic division and
adrenal secretion have the same action 22-39

ix

X CONTENTS

CHAPTER III

PAGES

METHODS OF DEMONSTRATING ADRENAL SECRE-
TION AND ITS NERVOUS CONTROL

The evidence that splanchnic stimulation induces ad-
renal secretion — The question of adrenal secretion
in emotional excitement — The method of securing
blood from near the adrenal veins — The method of
testing the blood for adrenin 40-51

CHAPTER IV

ADRENAL SECRETION IN STRONG EMOTIONS
AND PAIN

The evidence that adrenal secretion is increased in emo-
tional excitement — The evidence that adrenal secre-
tion is increased by "painful" stimulation — Confirma-
tion of our results by other observers .... 52-65

CHAPTER V

THE INCREASE OF BLOOD SUGAR IN PAIN AND
GREAT EMOTION

Glycosuria from pain — Emotional glycosuria — The role
of the adrenal glands in emotional glycosuria . 66-80

CHAPTER VI

IMPROVED CONTRACTION OF FATIGUED MUSCLE
AFTER SPLANCHNIC STIMULATION OF THE
ADRENAL GLAND

The nerve-muscle preparation — The splanchnic prepara-
tion — The effects of splanchnic stimulation on the
contraction of fatigued muscle — The first rise in the
muscle record — The prolonged rise in the muscle
record — The two factors : arterial pressure and adre-
nal secretion 81-94

CONTENTS xi

CHAPTEE VII

PAGES

THE EFFECTS ON CONTRACTION OF FATIGUED
MUSCLE OF VARYING THE ARTERIAL
BLOOD PRESSURE
The effect of increasing arterial pressure — The effect of
decreasing arterial pressure — An explanation of the
effects of varying the arterial pressure — The value
of increased arterial pressure in pain and strong
emotion 95-109

CHAPTEE VIII

THE SPECIFIC r6lE OP ADRENIN IN COUNTER-
ACTING THE EFFECTS OF FATIGUE

Variations of the threshold stimulus as a measure of
irritability — The method of determining the threshold
stimulus — The lessening of neuro-muscular irrita-
bility by fatigue — The slow restoration of fatigued
muscle to normal irritability by rest — jThg^uick res-
toration of fatigued muscle to norrnM irritability
by adrenin — The evidence that the restorative ac-
tion of adrenin is specific — The point of action of
adrenin in muscle 110-134

CHAPTEE IX

THE HASTENING OF THE COAGULATION OF BLOOD
r- BY ADRENIN

The graphic method of measuring the coagulation time
— The effects of subcutaneous injections of adrenin —
The effects of intravenous injections — The hastening
of coagulation by adrenin not a direct effect on the
blood . . . . / 135-160

CHAPTEE X

THE HASTENING OF COAGULATION OF BLOOD IN
PAIN AND GREAT EMOTION

Coagulation hastened by splanchnic stimulation — Co-
agulation not hastened by splanchnic stimulation if

xii CONTENTS

PAGES

the adrenal glands are absent — Coagulation hast-
ened by "painful" stimulation — Coagulation hastened
in emotional excitement 161-183

CHAPTEE SI

THE UTILITY OF THE BODILY CHANGES IN PAIN
AND GREAT EMOTION

The reflex nature of bodily responses in pain and the
major emotions, and the useful character of re-
flexes — The utility of the increased blood sugar as
a source of muscular energy — The utility of in-
creased adrenin in the blood as an antidote to the
effects of fatigue — The question whether adrenin
normally secreted inhibits the use of sugar in the
body — The vascular changes produced by adrenin
favorable to supreme muscular exertion — The changes
in respiratory function also favorable to great effort
— The effects produced in asphyxia similar to those
produced in pain and excitement — The utility of
rapid coagulation in preventing loss of blood . 184-214

'''^CHAPTER XII

THE ENERGIZING INFLUENCE OF EMOTIONAL EX-
CITEMENT

"Reservoirs of power" — The excitements and energies of
competitive sports — Frenzy and endurance in cere-
monial and other dances — The fierce emotions and
struggles of battle — The stimulating influence of
witnesses and of music — The feeling of power . 215-231

^ CHAPTER XIII
THE NATURE OF HUNGER

Appetite and hunger — The sensation of hunger — The
theory that hunger is a general sensation — Weak-
ness of the assumptions underlying the theory that
hunger is a general sensation — Body need may exist
without hunger — The theory that hunger is of gen-

CONTENTS xiii

PAGES

eral origin does not explain the quick onset and the
periodicity of the sensation — The theory that hunger
is of general origin does not explain the local refer-
ence — Hunger not due to emptiness of the stomach
— Hunger not due to hydrochloric acid in the empty
stomach — ^Hunger not due to turgescence of the gas-
tric mucous membrane — Hunger the result of con-
tractions — The "empty" stomach and intestines con-
tract — Observations suggesting that contractions
cause hunger — The concomitance of contractions and
hunger in man 232-266

•^CHAPTER XIV

THE INTERRELATIONS OF EMOTIONS

^Antagonism between emotions expressed in the sym-
pathetic and in the cranial divisions of the auto-
nomic system — Antagonism between emotions ex-
pressed in the sympathetic and in the sacral di-
visions of the autonomic system — The function of
hunger — The similarity of visceral effects in differ-
ent strong emotions and suggestions as to its psy-
chological significance 267-284

CHAPTER XV

ALTERNATIVE SATISFACTIONS FOR THE FIGHT-
ING EMOTIONS

Support for the militarist estimate of the strength of
the fighting emotions and instincts — Growing op-
position to the fighting emotions and instincts as
displayed in war — The desirability of preserving the
martial virtues — Moral substitutes for warfare — ^Phy-
sical substitutes for warfare — The significance of in-
ternational athletic competitions 285-301

^

A LIST OF PUBLISHED RESEARCHES FROM THE
PHYSIOLOGICAL LABORATORY IN HARVARD
UNIVERSITY 302-303

INDEX 305

BODILY CHANGES m PAIJ^,
HUJ^GER, FEAR AI^D RAGE

CHAPTER I

THE EFFECT OF THE EMOTIONS ON
DIGESTION

The doctrine of Imman development from sub-
human antecedents lias done much to unravel the
complex nature of man. As a means of interpre-
tation this doctrine has been directed chiefly
toward the solving of puzzles in the peculiarities
of anatomical structure. Thus arrangements in
the human body, which are without obvious util-
ity, receive rational explanation as being vestiges
of parts useful in or characteristic of remote an-
cestors — parts retained in man because of age-
long racial inheritance. This mode of interpreta-
tion has proved applicable also in accounting for
functional peculiarities. Expressive actions and(
gestures — the facial appearance in anger, for ex-'
ample — observed in children and in widely dis-
tinct races, are found to be innate, and are best
explained as the retention in human beings of
responses which are similar in character in lower
animals.

2 BODILY CHANGES

From this point of view biology has contributed
much to clarify our ideas regarding the motives
of human behavior. The social philosophies
which prevailed during the past century either
assumed that conduct was determined by a cal-
culated search for pleasure and avoidance of pain
or they ascribed it to a vague and undefined
faculty named the conscience or the moral sense.
Comparative study of the behavior of men and
of lower animals under various circumstances,
however, especially with the purpose of learning
the source of prevailing impulses, is revealing the
inadequacy of the theories of the older psychol-
ogists. More and more it is appearing that in
men of all races and in most of the higher ani-
mals, the springs of action are to be found in
the tafluence of_certain emotions wh ich express
themselv es in ch aracteristic ins tinctive act^.

The role which these fundamental responses in
the higher organisms play in the bodily economy
has received little attention. As a realm for in-
vestigation the bodily changes in emotional ex-
citement have been left by the physiologists to
the philosophers and psychologists and to the
students of natural history. These students, how-
ever, have usually had too slight experience in
the detailed examination of bodily functions to
permit them to follow the clues which superficial
observation might present. In consequence our

EMOTIONS AND DIGESTION 3

knowledge of emotional states has been meagre.
There are, of course, many surface manifesta-
tions of excitement. The contraction of blood
vessels with resulting pallor,' the pouring out of
"cold sweat," the stopping of saliva-flow so that
the "tongue cleaves to the roof of the mouth," the
dilation of the pupils, the rising of the hairs, the
rapid beating of the heart, the hurried respira-
tion, the trembling and twitching of the muscles,
especially those about the lips — all these bodily ]
changes are well recognized accompaniments of
pain and great emotional disturbance, such as
-f^r^ horror and deep disgust. But these dis- /
turbances of the even routine of life, which have
been commonly noted, are mainly superficial and
therefore readily observable. Even the increased
rapidity of the heart beat is noted at the surface
in the pulsing of the arteries. There^re, how-
ever^^ other organs, hid den deep— io—the-^body,
which do not reveal so obviously as the struc-
tures near or in the 's1on^""tEe disturbances of
action which attend states of intense feeling.
Special methods^'musT he used to deteraiine
whether thjesedeep-Jying organs also are included
in the complex of an emotional* agitation.

* In the T^ g of the term "emotign", the meaning here is
not restricted tit violent affective states, but includes "feel-,
mgs" and other affective experiences. At times, also, in
order to avoid awkward expressions, the term is used in the
popular manner, as if the "feeling" caused the bodily change.

A BODILY CHANGES

Among the organs that are affected to an im-
portant degree by feelings are those concerned
with digestion. And the relations of feelings to
the activities of the alimentary canal are of par-
ticular interest, because recent investigations have
shoAvn that not only are the first stages of the
digestive process normally started by the pleasur-
able taste and smell and sight of food, but also
( that pain and great emotional excitement can
seriously interfere with the starting of the pro-
cess or its continuation after it has been started.
Thus there may be a conflict of feelings and of
their bodily accompaniments — a conflict the inter-
esting bearing of which we shall consider later.

Emotions Favorable to Normal Secretion of the
Digestive Juices

The feelings or affective states favorable to
the digestive functions have been studied fruit-
fully by Pawlow,^ of Petrograd, through in-
genious experiments on dogs. By the use of care-
ful surgical methods he was able to make a side
pouch of a part of the stomach, the cavity of
which was wholly separate from the main cavity
in which the food was received. This pouch was
supplied in a normal manner with nerves and
blood vessels, and as it opened to the surface of
the body, the amount and character of the. gastric
juice secreted by it under various conditions

EMOTIONS AND DIGESTION 5

could be accurately determined. Secretion by that
part of the stomach wall which was included in
the pouch was representative of the secretory
activities of the entire stomach; The arrange-
ment was particularly advantageous in providing
the gastric juice unmixed with iood. In some of
the animals thus operated upon an opening was
also made in the esophagus so that when the
fQiM^a^s-swaile3sSkd7itdid~not pass to the stom- r
ach but propped out on the way. All the pleas-
ures of eating were thus experienced, and there
was no necessity of stopping because of a sense
of fulness. This process was called "sham feed- \
ingj.' The well-being of these animals was care-
fully attended to, they lived the normal life of
dogs, and in the course of months and years be-
came the pets of the laboratory.

By means of sham feeding Pawlow showed that
the chewing and swallowing of food which the
dogs relishedi.resulted, after a delay of about five
minutes, in a flow of natural gastric juice from
the side pouch of the stomach — a flow which per-
sisted as long as the dog chewed and swallowed
the food, and continued for some time after eat-
ing ceased. Evidently the presence of food in
the stomach is not a prime condition for gastric
secretion. And since the flow occurred only when
the dogs had an appetite, and the material pre-
sented to them was agreeable, the conclusion

BODILY CHANGES

as justified that this was a ivTiB-'^psjchie
jcretion.

The mere sight or smell of a favorite food may
tart the pouring out of gastric juice, as was
oted many years ago by Bidder and Schmidt ^
1 a hungry dog which had a fistulous opening
irough the body wall into the stomach. This
bservation, reported in 1852, was confirmed later
y Schiff and also still later by Pawlow. That
le mouth "watej*^" "with a flow of saliva when
alatable food is seen or smelled has long been
ach common knowledge that the expression, "It
lakes my mouth water," is at once recognized as
le highest testimony to the attractiveness of an
ppetizing dish. That the stomach also "waters"
1 preparation for digesting the food which is to
e taken is clearly proved by the above cited ob-
Brvations on the dog.

The importance of the initial psychic secretion
f saliva for further digestion is indicated when,
1 estimating the function of taste for the pleas-
res of appetite, we realize that materials can
e tasted only when dissolved in the mouth and
lereby brought into relation with the taste or-
ans. The saliva which "waters" the mouth as-
ures the dissolving of dry but soluble food even
^hen it is taken in large amount.

The importance of the initial psychic secretion
f gastric juice is made clear by the fact that con-

"EMOTIONS AND DIGESTION 7

timiance of the flow of tMs juice during diges-
tion is provided by the action of its acid or its
digestive products on the mucous membrane of
the pyloric end of the stomach, and that secre-
tion of the pancreatic juice and bile are called
forth by the action of this same acid on the mu-
cous membrane of the duodenum. _The_proper
s tarting of the digesjdve. process, therefore, ,i8
conditioned by the satisfactions of the palate,and
fhe~cons equent flow of the first digestive fluids.,
The facts brought out experimentally in studies
on lower animals are doubtless true also of man.
Not very infrequently, because of the accidental
swallowing of corrosive substances, the esopha-
gus is so injured that, when it heals, the sides
grow together and the tube is closed. Under
these circumstances an opening has to be made
into the stomach through the side of the body and
then the individual chews his food in the usual
manner, but ejects it from his mouth into a tube
which is passed through the gastric opening. The
food thus goes from mouth to stomach through
a tube outside the chest instead of inside the
chest. As long ago as 1878, Eichet,* who had
occasion to study a girl whose esophagus was
closed and who was fed through a gastric fistula,,
reported that whenever the girl chewed or tasted |
a highly sapid substance, such as sugar or lemon \
juice, while the stomach was empty, there flowed I

8 BODILY CHANGES

from the fistula a considerable quantity of gastric
juice. A number of later observers * have had
similar cases in human beings, especially in chil-
dren, and have reported in detail results which
correspond remarkably with those obtained in the
laboratory. Hornborg* found that when the
little boy whom he studied chewed agreeable food
a more or less active secretion of gastric juice
invariably started, whereas the chewing of an
indifferent substance, as gutta-percha, was fol-
lowed by no secretion. All these observations
clearly demonstrate that the normal flow of the
first digestive fluids, the saliva and the gastric
juice, is favored by the pleasurable feelings
which accompany the taste and smell of food dur-
ing mastication, or which are roused in anticipa-
tion of eating when choice morsels are seen or
smelled.

These facts are of fundamental importance in
the serving of food, especially when, through ill-
ness, the appetite is fickle. The degree of dainti-
ness with which nourishment is served, the little
attentions to esthetic details — the arrangement
of the dishes, the small portions of food, the
flower beside the plate — all may help to render
food pleasing to the eye and savory to the nos-
trils and may be the deciding factors in determin-
ing whether the restoration of strength is to be-
gin or not.

EMOTIONS AND DIGESTION 9

Emotions Unfavorable to the Normal Secretion of the
Digestive Juices

The conditions favorable to proper digestion
are wholly abolished when unpleasant feelings
such as vexation and worry and anxiety, or great
emotions such as anger and «f ear, are allowed to)
prevail. This fact, so far as the salivary secre-
tion is concerned, has long' been known. The
dry mouth of the anxious person called upon to
speak in public is a common instance; and the
"ordeal of rice," as employed in India, was a prac-
tical utilization of the knowledge that excitement
is capable of inhibiting the salivary flow. When
several persons were suspected of crime, the con-
secrated rice was given to them all to chew, and
after a short time it was spit out upon the leaf of
the sacred fig tree. If anyone ejected it dry, that
was taken as proof that fear of being discovered
had stopped the secretion, and consequently he
was adjudged guilty.^

What has long been recognized as true of the
secretion of saliva has been provedOtrue also of
the secretion of gastric juice. ^^ For example,
Hornborg was unable to confirm in his little pa-
tient with a gastric fistula the observation by
Pawlow that when hunger is present the mere
seeing of food results in a flow of gastric juice.
Hornborg explained the difference between his
and Pawlow's results by the different ways '•in

\

10 BODILY CHANGES

which, the boy and the dogs faced the situation.
When food was shown, but withheld, the hungry
dogs were all eagerness to secure it, and the juice
very soon began to flow. The boy, on the con-
trary, became vexed when he could not eat at
once, and began to c^y; then no secretion ap-
peared. Bogen also has reported the instance of
a child with closed esophagus and gastric fistula,
who sometimes fell into such a passion in con-
sequence of vain hoping for food that the giving
of the food, after the child was calmed^was not
followed by any flow of the secretion.

The inhibitory influence of excitement has i^lso
been seen in lower animals under laboratory con-
ditions. Le Conte " declares that in studying
gastric secretion it is necessary to avoid all cir-
cumstances likely to provoke emotional reactions.
In the fear which dogs manifest when first
brought into stran ge surroundin gsJie found that
activity of the gastric glands may be completely
suppressed. The suppression occurred even if
the dog had eaten freely and was then disturbed
— as, for example, by being tied to a table. "When
the animals became accustomed to the experi-
mental procedure, it no longer had an inhibitory
effect. The studies of Bickel and Sasaki "^ con-
firm and define more precisely this inhibitory
effect of strong emotion on gastric secretion.
They observed the inhibition on a dog with an

EMOTIONS AND DIGESTION 11

esophageal fistula, and with, a side pouch of the
stomach, which, as in Pawlow's experiments,
opened only to the exterior. In this dog Bickel
and Sasaki noted, as Pawlow had, that sham feed-
ing was attended by a copious flow of gastric
juice, a true psychic secretion, resulting from the
pleasurable taste of the food, (in a typical in-j
stance the sham feeding lasted five minutes, and
the secretion continued for twenty minuteg^, dur-j
ing which time 66.7 cubic centimeters of pure gas-
tric juice were produced.

vx\

On another day a cat was brought into the V^ v V ; ;
presence of the dog, whereupon the dog flew into "^^^ , ^s,^i
a great fury. The cat was soon removed, and ^^ '\/J'i'
the dog pacified. Now the dog was again given \. >^^
the sham feeding for five minutes. In spite of "^
the fact that the animal was hungry and ate
eagerly, there was no secretion worthy of men-
tion. During a period of twenty minutes, cor-
responding to the previous observation, only 9
cubic centimeters of acid fluid were produced, and
this was rich in mucus. It is evident that in the
dog, as in the boy observed by Bogen, strong emo-
tions can so profoundly disarrange the mechanisms ^yK
of secretion that the pleasurable excitation which
accompanies the taking of food cannot cause th0
normal flow.

On another occasion Bickel and Sasaki started
gastric secretion in the dog by sham feeding, and

12 BODILY CHANGES

when the flow of gastric juice had reached a cer-
tain height, the dog was infuriated for five min-
utes by the presence of the cat. During the next
(fifteen minutes there appeared only a few drops
' of a very mucous secretion. Evidently in this
instance a physiological process, started as an
accompaniment of a psychic state quietly pleas-
urable in character, was almost entirely stopped
after another psychic state violent in character.
It is noteworthy that in both the favorable and
unfavorable results of the emotional excitement
illustrated in Bickel and Sasaki's dog the effects
persisted long after the removal of the exciting
condition. This fact, in its favorable aspect,
Bickel ^ was able to confirm in a girl with
esophageal and gastric fistulas; the gastric se-
cretion long outlasted the period of eating, al-
though no food entered the stomach. (_ The in-
fiuences unfavorable to digestion, however, are
stronger than those which promote it. And
evidently, if the digestive process, because of
emotionah disturbance, is for some time inhibited,
the swallowing of food which must lie stagnant in
the stomach is a most irrational procedure.^ If a
child has experienced an outburst of passion, it
is well not to urge the taking of nourishment soon
afterwards. Macbeth's advice that "good diges-
tion wait on appetite and health on both," is now
well-founded physiology.

EMOTIONS AND DIGESTION 13

Other digestive glands than the salivary and
the gastric may be checked ia emotional excite-
ment. Eecently Oechsler^ has reported that in
such psychic disturbances as were shown by
Bickel and Sasaki to be accompanied by sup-
pressed secretion of the gastric juice, the secre-
tion of pancreatic juice may be stopped, and the |
flow of bile definitely checked. All the means of
bringing about chemical changes in the food may
be thus temporarily abolished.

Emotions Favorable and Unfavorable to the Contractions
OP THE Stomach and Intestines

The secretions of' the digestive glands and the
chemical changes wrought by them are of little
worth unless the food is carried onward through
the alimentary canal into fresh regions of diges-
tion and is thoroughly exposed to the intestinal
wall for absorption. In studying these mechani-
cal aspects of digestion I was led to infer ^^ that
(^just as there is a psychic secretion, so likei
wise there is probably a "psychic tone" or "psy-l
chic contraction" of the gastro-intestinal musclesl
as a result of taking food. For if the vagus nerve
supply to the stomach is cut immediately before
an animal takes food, the usual contractions of y
the gastric wall, as seen by the Eontgen rays, dc
not occur; but if these nerves are cut after fooc
has been eaten with relish, the contractions which

14 BODILY CHANGES

have started continue without cessation?^ The
nerves in both conditions were severed under
anesthesia, so that no element of pain entered
into the experiments. In the absence of hunger,
which in itself provides a contracted stomach,^^
the pleasurable taking of food may, therefore, be
a primary condition for the appearance of natural
contractions of the gastro-intestinal canal.

Again just as the secretory activities of the
stomach are unfavorably influenced by strong
emotions, so also are the movements of the stom-
ach; and, indeed, the movements of almost the
entire alimentary canal are wholly stopped dur-
ing great excitement. In my earliest observa-
tions on the movements of the stomach ^^ I had
difficulty because in some animals the waves of
contraction were perfectly evident, while in others
there was no sign of activity. Several weeks
passed before I discovered that this difference
was associated with a difference of sex. In order
to be observed with Eontgen rays the animals
were restrained in a holder. Although the holder
was comfortable, the male cats, particularly the
young males, were restive and excited on being
fastened to it, and under these circumstances
gastric peristaltic waves were absent; the female
cats, especially if elderly, usually submitted with
calmness to the restraint, and in them the waves
had their normal occurrence. Once a female with

EMOTIONS AND DIGESTION 15

kittens turned from her state of quiet content-
ment to one of apparent restless anxiety. The
movements of the stomach immediately stopped,
the gastric wall became wholly relaxed, and only
after the animal had been petted and began to
purr did the moving waves start again on their
course, (^y covering the cat's mouth and nose\
with the fingers until a slight distress of breath- 1
ing is produced, the stomach contractions can be j
stopped at willT^ In the cat, t herefo je , anv sign [ilh
of^ rage or fear, such as was seen in dogs by Le /
Conte and by Bickel and Sasaki(was accompanied! J
by a total abolition of the movements of the!
stomach.y Even indications of slight anxiety may
be attended by complete absence of the churning
waves. In a vigorous young male cat I have
watched the stomach for more than an hour by
means of the Eontgen rays, and during that time
not the .slightest beginning of peristaltic activity
appeared; yet the only visible indication of ex-
citement in the animal was a continued quick
twitching of the tail to and fro. What is true
of the cat I have found true also of the rabbit,
dog and guinea-pig ^* — ^very mild emotional dis-
turbances are attended by abolition of peristalsis.
The observations on the rabbit have been con-
firmed by Auer,^* who found that the handling
of the animal incidental to fastening it gently
to a holder stopped gastric peristalsis for a

16 BODILY CHANGES

variable length of time. And if the animal was
startled for any reason, or struggled excitedly,
peristalsis was again abolished. The observa-
tions on the dog also have been confirmed; Lom-
meP^ found that small dogs in strange sur-
roundings might have no contractions of the
stomach for two or three hours. And whenever
the animals showed any indications of being un-
comfortable or distressed, the contractions were
inhibited and the discharge of contents from the
stomach checked.

Like the peristaltic waves in the stomach, the

peristalsis and the kneading movements (seg-

// t mentation) in the small intestine, and the re-

; versed peristalsis in the large intestine all cease

' whenever the observed animal shows signs of

; emotional excitement.

There is no doubt that just as the secretory
activity of the stomach is affected in a similar
fashion in man and in lower animals, so likewise
gastric and intestinal peristaltic waves are
stopped in man as they are stopped in lower ani-
mals, by worry and anxiety and the stronger
f affective states. (^ The conditions of mental discord
\ may thus give rise to a sense of gastric inertia.
For example, a patient described by Miiller ^^
testified that anxiety was always accompanied by
a feeling of weight, as if the food remained in
the stomach. Every addition of food caused an

EMOTIONS AND DIGESTION 17

increase of the trouble. Strong emotional states
in this instance led almost always to gastric dis-
tress, which persisted, according to the grade and
the duration of the psychic disturbance, between
a half-hour and several days. The patient was
not hysterical or neurasthenic, but was a very
sensitive woman deeply affected by moods.

The feeling of heaviness in the stomach, men-|
tioned in the foregoing case, is not uncommonlj
complained of by nervous persons, and may be
due to stagnation of the contents. That sue!
stagnation occurs is shown by the following in-
stance. A refined and sensitive woman, who had
had digestive difficulties, came with her husband
to Boston to be examined. They went to a hotel
for the night. The next morning the woman ap-
peared at the consultant's office an hour after
having eaten a test meal. An examination of the
gastric contents revealed no free acid, no diges-
tion of the test breakfast, and the presence of a
considerable amount of the supper of the pre-
vious evening. The explanation of this stagna-
tion of the food in the stomach came from the
family doctor, who reported that the husband
had made the visit to the city an occasion for be-
coming uncontrollably drunk, and that he had
by his escapades given his wife a night of turbu-
lent anxiety. The second morning, after the
woman had had a good rest, the gastric eon-

18 BODILY CHANGES

tents were again examined; the proper acidity
was found, and the test breakfast had been nor-
mally digested and discharged.

These cases are merely illustrative and doubt-
less can be many times duplicated in the experi-
ence of any physician concerned largely with di-
gestive disorders., -^Indeed, the opinion has been
expressed that a great majority of the cases of
gastric indigestion that come for treatment are
functional in character and of nervous origin.
It is the emotional element that seems most char-
acteristic of these cases.^To so great an extent
is this true that Rosenbach has suggested that as
a term to characterize the cause of the distur-
bances, Q"emotional" dyspepsia is better than
"nervous" dyspepsia.^'^

The Disturbing Effect of Pain on Digestion

The advocates of the theory of organic evolu-
tion early pointed out the similarity between the
bodily disturbances in pain and in the major emo-
tions. The alterations of function of internal or-
gans they could not know about. The general
statement, however, that pain evokes the same
changes that are evoked by emotion, is true also
M these deep-lying structures. Wertheimer^^
proved many years since that stimulation of a
I sensory nerve in an anesthetized animal — such
Istimulation as in a conscious animal would in-

<

EMOTIONS AND DIGESTION 19

duce pain — quickly abolished the contractions of
the stomach. And Netschaiev, working in Paw-
low's ^® laboratory, showed that excitation of
the sensory fibres in the sciatic nerve for two or
three minutes resulted ia an inhibition of the
secretion of gastric juice that lasted for several
hours. Similar effects from painful experience
have been not uncommonly noted in human be-
ings. Mantegazzaj^"* in his account of the physi-
ology of pain, has cited a number of such ex-
amples, and from them he has concluded tha1(pain^ >
interferes with digestion by lessening appetite
and by producing various forms of dyspepsia,
with arrest of gastric digestion, and with vomit-
ing and diarrhea.^ The expression, "sickening,
pain" is testimony to the power of strong sensory
stimulation to upset the digestive processes pro-
foundly. Vomiting is as likely to follow violent
pain as it is to follow strong emotion. A "sick
headache" may be, indeed, a sequence of events
in which the pain from the headache is primary,
and the nausea and other evidences of digestive
disorder are secondary.

As the foregoing account has shown, emotional
conditions or "feelings" may be accompanied by
quite opposite effects in the alimentary canal,
some highly favorable to good digestion, some
highly disturbing. It is an interesting fact that
the feelings having these antagonistic actions are

^

20 BODILY CHANGES

typically expressed through nerve supplies which
are correspondingly opposed in their influence
on the digestive organs. The antagonism between
these nerve supplies is of fundamental impor-
tance in understanding not only the operation of
conditions favorable or unfavorable to digestion
but also in obtaining insight into the conflicts of
emotional states. Since a consideration of the
arrangement and mode of action of these nerves
will establish a firm basis for later analysis and
conclusions, they will next be considered.

EEFEEENCES

^ Pawlow : The Work of the Digestive Glands, London,
1902.

^ Bidder and Schmidt : Die Verdauungssafte und der
StofFwechsel, Leipzig, 1852, p. 35.

^ Eiehet : Journal de I'Anatomie et de la Physiologie,
1878, xiv, p. 170.

* See Hornborg : Skandinavisches Archiv f iir Physiologie,
1904, XV, p. 248. Cade and Latarjet : Journal de Physiologie
et Pathologie Generale, 1905, vii, p. 221. Bogen : Archiv f iir
die gesammte Physiologie, 1907, cxvii, p. 156. Lavenson:
Archives of Internal Medicine, 1909, iv, p. 271.

^ Lea : Superstition and Force, Philadelphia, 1892, p. 344.
8Le Conte: La Cellule, 1900, xvii, p. 291.
^ Bickel and Sasaki : Deutsche medizinische Wochen-
schrift, 1905, xxxi, p. 1829.

* Bickel : Berliner klinische Wochensohrift, 1906, xliii, p.
845.

° Oechsler : Internationelle Beitrage zur Pathologie und
Therapie der Ernahrungstorungen, 1914, v, p. 1.

1" Cannon : The Mechanical Factors of Digestion, London
and New York, 1911, p. 200.

EMOTIONS AND DIGESTION 21

''■ Cannon and Washburn : American Journal of Physi-
ology, 1912, xxix, p. 441.

^2 Cannon : The American Journal of Physiology, 1898, i,
p. 38.

^^ Cannon : American Journal of Physiology, 1902, vii,
p. xxii.

^* Auer : American Journal of Physiology, 1907, xviii,
p. 356.

^° Lommel : Miinchener medizinische Wochenschrift,
1903, i, p. 1634.

^* Miiller : Deutsches Archiv f iir klinische Medicin, 1907,
Ixxxix, p. 434.

" Eosenbach : Berliner klinische Wochenschrift, 1897,
xxxiv, p. 71

18 Wertheimer : Archives de Physiologic, 1892, xxiv, p.
379.

1' Pawlow : Loc. cU., p. 56.

^^ Mantegazza : Fisiologia del Dolore, Florence, 1880, p.
123.

CHAPTER II

THE GENEKAL ORGANIZATION OF THE
VISCERAL NERVES CONCERNED IN EMOTIONS

The structures of the alimentary canal which
are brought into activity during the satisfactions
of appetite or are checked in their activity during
pain and emotional excitement are either the se-
creting digestive glands or the smooth muscle
which surrounds the canal. Both the gland cells
and the smooth-muscle cells differ from other
tells which are subject to nervous influence —
those of striated, or skeletal, muscle — in not being
directly under voluntary control and in being
slower in their response. The muscle connected
with the skeleton responds to stimulation within
two or three thousandths of a second; the delay
with gland cells and with smooth muscle is more
likely to be measured in seconds than in fractions
of a second.

The Outlying Neurones
The skeletal muscles receive their nerve supply
direct from the central nervous system, i. e., the

22

VISCERAL NERVES 23

nerve fibres distributed to these muscles are parts
of neurones whose cell bodies lie within the brain
or spinal cord. The glands and smooth muscles! /^
of the viscera, on the contrary, are, so far as is ;:
now known, never innervated directly from the
central nervous system.* The neurones reaching!
out from the brain or spinal cord never come into
immediate relation with the gland or smooth-
muscle cells ; there are always interposed between
the cerebrospinal neurones and the viscera extra
neurones whose bodies and processes lie wholly
outside the central nervous system. They are
represented in dotted lines in Fig. 1. I have sug-
gested that possibly these outlying neurones act
as "transformers," modifying the impulses re-
ceived from the central source (impulses suited to
call forth the quick responses of skeletal muscle),
and adapting these impulses to the peculiar, more
slowly-acting tissues, the secreting cells and vis-
ceral muscle, to which they are distributed.^

The outlying neurones typically have their cell
bodies grouped in ganglia (Gr's, Fig. 1) which, in
the trunk region, lie along either side of the spinal
cord and in the head region and in the pelvic
part of the abdominal cavity are disposed near
the organs which the neurones supply. In some
instances these neurones lie wholly within the

* The special case of the adrenal glands will be considered
later.

Tear gland
Dilator of pupil

Artery of salivary gland

Hair

Surface artery

Sweat gland

Heart

Hair

Surface artery
^-—^ Sweat gland

(l^^ Liver

Stomach

Visceral artery
Spleen

Intestine

Adrenal gland

Hair

Surface artery

Sweat gland

Colon

Bladder

Rectum

Artery of ejrternal
genitals

Figure 1. — Diagram of the more important distributions of the
autonomic nervous system. The brain and spinal cord are repre-
sented at the left. The nerves to skeletal muscles are not repre-
sented. The preganglionic fibres of the autonomic system are in
solid Unes, the postganglionic in dash-lines. The nerves of the
cranial and sacral divisions are distinguished from those of the
thoracioo-lumbar or "sympathetic," division by broader lines. A -|-
mark indicates an augmenting effect on the activity of the organ;
a — mark, a depressive or inhibitory effect. For further descrip-
tion see text.

yiSCERAL NEEVES 25

structure which they innervate (see e. g., the heart
and the stomach, Fig. 1). In other instances the
fibres passing out from the ganglia — the so-called
"postganglionic fibres" — may traverse long dis-
tances before reaching their destination. The in-
nervation of blood vessels in the foot by neurones
whose cell bodies are in the lower trunk region
is an example of this extensive distribution of the
fibres.

The Three Divisions of the Outlying Neurones

As suggested above, the outlying neurones are
connected with the brain and spinal cord by
neurones. whose cell bodies lie within the central
nervous organs. These connecting neurones, rep-
resented in continuous lines in Fig. 1, do not pass
out in a continuous series all along the cerebro-
spinal axis. Where the nerves pass out from the
spinal cord to the fore and hind limbs, fibres are
not given off to the ganglia. Thus these connect-
ing or "preganglionic" fibres are separated into
three divisions. In front of the nerve roots for
the fore limbs is the head or cranial division, be-
tween the nerve roots for the fore limbs and those
for the hind limbs is the trunk division (or thorad-
ico-lumbar division, or, in the older terminology,
the "sympathetic system"); and after the nerve
roots for the hind limbs the sacral division.

This system of outlying neurones, with post-

26 BODILY CHANGES

ganglionic fibres innervating the viscera, and with
preganglionic fibres reaching out to them from
the cerebrospinal system, has been called by
Langley, to whom we are indebted for most of
our knowledge of its organization, the autonomic
nervous system.^ This term indicates that the
structures which the system supplies are not sub-
ject to voluntary control, but operate to a large
degree independently. As we have seen, a highly
potent mode of influencing these structures is
through conditions of pain and emotional excite-
ment. The parts of the autonomic system — the
cranial, the sympathetic, and the sacral— have a
number of peculiarities which are of prime im-
portance in accounting for the bodily manifesta-
tions of such affective states.

The Extensive Distribution of Neurones of the "Sympa-
thetic" Division and Their Arrangement for Diffuse
Action

/The fibres of the sympathetic divisioiJ^differ
from those of the other two divisions inybeing
/aistributed through the body very widely. They
go to the eyes, ^causing dilation of the pupils.
They go to the heart and, when stimulated, they
cause it to beat rapidly. They carry impulses to
arteries and arterioles of the skin, the abdominal
viscera, and other parts, keeping the smooth mus-
cles of the vessel walls in a state of slight con-

VISCEEAL' NERVES 27

traction or tone, and thus serving to maintain
an arterial pressure sufficiently higli to meet sud-
den demands in any special region; or, in times
of special discharge of impulses, to increase the
tone and thus also the arterial pressure. They
are distributed extensively to the smooth muscle
attached to the hairs; and when they cause this
muscle to contract, the hairs are erected. They
go to sweat glands, causing the outpouring of
sweat. These fibres pass also to the entire length
of the gastro-intestinal canal. And t he inhibi-
^ion of diges^ve activity which, ^ as . we have
learned, occurs in pain and emotional states, i_s
due to impulses which are conducted outward by
the splanchnic nerves — the preganglionic fibres
that reach to the great ganglia in the upper abdo-
men (see Fig. 1) — and thence are spread by post-
ganglionic fibres all along the gut.* They in-
nervate likewise the genito-urinary tracts, causing
contraction of the smooth muscle of the internal
genital organs, and usually relaxation of the blad-
der. Finally they affect the liver, releasing the
storage of material there in a manner which may
be of great service to the body in tiine of need.
The extensiveness of the distribution of the fibres
of the sympathetic division is one of its most
prominent characteristics.

Another typical feature of the sympathetic di-
vision is an arrangement of neurones for diffuse

28 BODILY CHANGES

discharge of tlie nerve impulses. As shown dia-
grammatically in Fig. 1, the preganglionic fibres
from the central nervous system may extend
through several of the sympathetic ganglia and
give off in each of them connections to cell bodies
of the outlying neurones. Although the neurones
which transmit sensory impulses from the skin
into spinal cord have similar relations to nerve
cells lying at ditferent levels of the cord, the op-
eration in the two cases is quite different. In
the spinal cord the sensory impulse produces di-
rected and closely limited effects, as, for example,
when reflexes are being evoked in a "spinal" ani-
mal (i. e., an animal with the spinal cord isolated
from the rest of the central nervous system), the
left hind limb is nicely lifted, in response to a
harmful stimulus applied to the left foot, without
widespread marked involvement of the rest of
the body in the response.* In the action of the
sympathetic division, on the contrary, the con-
nection of single preganglionic fibres with nu-
merous outlying neurones seems to be not at all
arranged for specific effects in this or that par-
ticular region. There are, to be sure, in different
circumstances variations in the degree of ac-
tivity of different parts; for example, it is prob-
able that dilation of the pupil in the cat occurs
more readily than erection of the hairs. It may
be in this instance, however, that specially direct

VISCEEAL NEEVES 29

pathways to the eye are present for common use
in non-emotional states (in dim light, e. g.), and
that only slight general disturbance in the central
nervous system, therefore, would be necessary to
send impulses by these well-worn courses. Thus
for local reasons (dust, e. g.) tears might flow
from excitation of the tear glands by sympathetic
impulses, although other parts innervated by this
same division might be but little disturbed. We
have no means of voluntarily wearing these path-
ways, however, and^both from anatomical and
physiological evidence^ the neurone relations in
the sympathetic division of the autonomic system
seem devised for widespread diffusion of nervous
impulses.

The Arrangement of Neurones of the Cranial and Sacral
Divisions for Specific Action

The cranial and sacral autonomic divisions
differ from the sympathetic in having only re-
stricted distribution (see Fig. 1). The third cran-
ial nerves deliver impulses from the brain to
ganglia in which lie the cell bodies of neurones
innervating smooth muscle only in the front of
the eyes. The vagus nerves are distributed to
the lungs, heart, stomach, and small intestine.
As shown diagrammatically in Fig. 1, the out-
lying neurones in the last three of these organs
lie within the organs themselves. By this ar-
rangement, although the preganglionic fibres of

30 BODILY CHANGES

the vagi are extended in various directions to
structures of quite diverse functions, singleness
and separateness of connection of the peripheral
organs with the central nervous system is as-
sured. The same specific relation between effer-
ent fibres and the viscera is seen in the sacral
autonomic. In this division the preganglionic
fibres pass out from the spinal cord to ganglia
lying in close proximity to the distal colon, the
bladder, and the external genitals. And the post-
ganglionic fibres deliver the nerve impulses only
to the nearby organs. Besides these innervations
the cranial and sacral divisions supply individual
arteries with "dilator nerves" — nerves causing
relaxation of the particular vessels. Quite typi-
cally, therefore, the efferent fibres of the two
terminal divisions of the autonomic differ from
those of the mid-division in having few of the
distributed connections characteristic of the mid-
division, and m. innervating distinctively the or-
gans to which they are distributed. The cranial
and sacral preganglionic fibres resemble thus the
nerves to skeletal muscles, and their arrangement
provides similar possibilities of specific and sepa-
rate action in any part, without action in other
parts.

The Cranial Division a Conserveb of Bodily Resources

\ The cranial autonomic, represented by the

yagus nerves, is the part of the visceral nervous

VISCEEAL NEEVES 31

system concerned in the psychic secretion of the
gastric juice. Pawlow showed that when these
nerves are severed psychic secretion is abolished.
The cranial nerves to the salivary glands are sim-
ilarly the agents for psychic secretion in these
organs, and are known to cause also dilation of the
arteries supplying the glands, so that during ac-
tivity the glands receive a more abundant flow of
blood. As previously stated (see p. 13), the evi-
dence for a psychic tonus of the gastro-intestinal
musculature rests on a failure of the normal con-
tractions if the vagi are severed before food is
taken, in contrast to the continuance of the con-
tractions if the nerves are severed just after-
wards. The vagi artificially excited are well-
known as stimulators of increased tone in the
smooth muscle of the alimentary canal. Aside
from these positive effects on the muscles of the
digestive tract and its accessory glands, cranial
autonomic fibres cause contraction of the pupH
of the eye, and slowing of the heart rate.

A glance at these various functions of the cra^
nial division reveals at once that they serve foi
bodily conservation. By narrowing the pupil oi
the eye they shield the retina from excessiv
light. By slowing the heart rate, they give th
cardiac muscle longer periods for rest and in'-
vigoration. And by providing for the flow ol
saliva and gastric juice and by supplying the mus

32 BODILY CHANGES

j cular tone necessary for contraction of the ali-

/ mentary canal, they prove fundamentally essen-

! tial to the processes of proper digestion and

i absorption by which energy-yielding material is

taken into the body and stored. To the cranial

division of the visceral nerves, therefore, belongs

;, the quiet service of building up reserves and forti-

f fying the body against times of need or stress.

The Sacral Division a Group of Mechanisms for Emptying

I Sacral autonomic fibres cause contraction of the
' rectum and distal colon and also contraction of
'' the bladder. In both instances the effects result
reflexly from stretching of the tonically con-
tracted viscera by their accumulating contents.
No affective states precede this normal action of
the sacral division and even those which accom-
pany or follow are only mildly positive ; a feeling
of relief rather than of elation usually attends
the completion of the act of defecation or mic-
turition — though there is testimony to the con-
trary.

I The sacral autonomic fibres also include, how-
lever, the nervi erigentes which bring about en-
gorgement of erectile tissue in the external geni-
Jtals. According to Langley and Anderson^ the
sacral nerves have no effect on the internal gen-
erative organs. The vasa deferentia and the
seminal vesicles whose rhythmic contractions

VISCEEAL NEEVES 33

mark the acme of sexual excitement in the male,
and the uterus whose contractions in the female
are probably analogous, are supplied only by
lumbar branches — part of the sympathetic divi-
sion. These branches also act in opposition to
the nervi erigentes and cause constriction of the
blood vessels of the external- genitals. The sexual
orgasm involves a high degree of emotional ex-
citement; but it can be rightly considered as es-
sentially a reflex mechanism; and, again in this
instance, distention of tubules, vesicles, and blood
vessels can be found at the beginning of the in-
cident, and relief from this distension at the end.
Although distention is the commonest occasion
for bringing the sacral division into activity it is
not the only occasion. Great emotion, such as is
accompanied by nervous discharges via the sym-
pathetic division, may also be accompanied by dis-
charges via the sacral fibres. The involuntary
voiding of the bladder and lower gut at times of
violent mental stress is well-known. Veterans of
wars testify that just before the beginning of a
battle many of the men have to retire temporarily
from the firing line. And the power of sights
and smells and libidinous thouglits to disturb the
regions controlled by the nervi erigentes proves
that this part of the autonomic system also has
its peculiar affective states. The fact that one
part of the sacral division, e. g., the distribu-

34 BODILY CHANGES

tion to the bladder, may be in abeyance, while
another part, e. g., the distribution to the rectum,
is active, illustrates again the directive discharge
of impulses which has been previously described
as characteristic of the cranial and sacral portions
of the autonomic system.

Like the cranial division, the sacral is engaged
in internal service to the body, in the performance
of acts leading immediately to greater comfort.

The Sympathetic DnasioN Antagonistic to Both the
Cranial and the Sacral

As indicated in the foregoing description many
of the viscera are innervated both by the cranial
or sacral part of the autonomic and by the sym-
pathetic. When the mid-part meets either end-
part in any viscus their effects are antagonistic.
Thus the cranial supply to the eye contracts the
pupil, the sympathetic dilates it; the cranial
slows the heart, the sympathetic accelerates it;
the sacral contracts the lower part of the large
intestine, the sympathetic relaxes it; the sacral
relaxes the exit from the bladder, the sym-
pathetic contracts it.N These opposed effects
are indicated in Fig. i by 4- for contraction, ac-
celeration or increased tone; and by - for inhibi-
tion, relaxation, or decreased tone.*

* The vagus nerve, when artificially stimulated, has a pri-
mary, brief inhibitory effect on the stomach and small intes-
tine ; its main function, however, as already stated, is to pro-

VISCERAL NEEVES 35

Sherrington lias demonstrated that the setting
of skeletal muscles in opposed groups about a
joint or system of joints — as in flexors and ex-
tensors — is associated with an internal organiza-
tion of the central nervous system that provides
for relaxation of one group of the opposed mus-
cles when the other group is made to contract.
This "reciprocal innervation of antagonistic mus-
cles," as Sherrington has called it,** is thus a
device for orderly action in the body. As the
above description has shown, there are peripheral
oppositions in the viscera corresponding to the
oppositions between flexor and extensor muscles.
In all probability these opposed innervations of
the viscera have counterparts in the organization
of neurones in the central nervous system. Sher4
rington has noticed, and I can confirm the obser-i
vation, that even though the sympathetic supplv
to the eye is severed and is therefore incapable on
causing dilation of the pupil, nevertheless the
pupil dilates in a paroxysm of anger — due, no
doubt (because the response is too rapid to be
mediated by the blood stream), to central inhibi-
tion of the cranial nerve supply to the constrictor
muscles — i. e., an inhibition of the muscles which
naturally oppose the dilator action of the sym-
pathetic. Pain, the major emotions — fear and

duce increased tone and contraction in these organs. This
double action of the vagus is marked thus, q: , in Fig. 1.

36 BODILY CHANGES

I rage — and also intense excitement, are manifested
^ in the activities of the sympathetic division.
When in these states impulses rush out over the
neurones of this division they produce all the
changes typical of sympathetic excitation, such
las dilating the pupils, inhibitmg digestion, caus-
I ing pallor, accelerating the heart, and various
' other well-known effects. The impulses of the
sympathetic neurones, as indicated by their domi-
nance over the digestive process, are capable of
readily overwhelming the conditions established
by neurones of the cranial division of the auto-
nomic system.

Neurones of the Sympathetic Division and Adrenal
Secretion Have the Same Action

Lying anterior to each kidney is a small body —
the adrenal gland. It is composed of an external
portion or cortex, and a central portion or me-
dulla. From the medulla can be extracted a sub-
stance, called variously suprarenin, adrenin, epi-
nephrin. or "adrenalin,"* which, in extraordinarily
minute amounts, affects the structures innervated
by the sympathetic division of the autonomic sys-

* The name "adrenalin" is proprietary. "Epinephrin" and
"adrenin" have been suggested as terms free from commer-
cial suggestions. As adrenin is shorter and more clearly
related to the common adjectival form, adrenal, I have fol-
lowed Schafer in using adrenin to designate the substance
produced physiologically by the adrenal glands.

VISCERAL NEEVES 37

tern precisely as if they were receiving nervous
impulses. For example, -when adrenin is injected
into the blood, it will cause pupils to dilate, hairs
to stand erect, blood vessels to be constricted, the
activities of the alimentary canal to be inhibited,
and sugar to be liberated from the liver. These
effects are not prfidueedJhy-action of the substance '
on the central nervous system, but by^ direct ac-j
tion on the organ itself.'^ And the effects oc-
cur even after the structures have been removed
from the body and kept alive artificially.
. The adrenals are glands of internal secretion, \
i. e., like the thyroid, parathyroid, and pituitary
glands, for example ; they have no connection with
the surface of the body, and they'' give out into^,^
the blood the material which they elaborate. /The
blood is carried away from each of them by the
lumbo-adrenal vein which empties either into the
renal vein or directly into the inferior vena cava
just anterior to the openings of the renal veins.
The adrenal glands are supplied by preganglionic
fibres of the autonomic group,* shown in solid
line in Fig. 1. This seems an exception to the
general rule that gland cells have an outlying
neurone between them and the neurones of tho
central nervous system. The medulla of the adre-
nal gland, however, is composed of modified nerve
cells, and may therefore be regarded as offering
exceptional conditions.

38 BODILY CHANGES

The foregoing brief sketch of the organization
of the autonomic system brings out a number of
points that should be of importance as bearing
on the nature of the emotions which manifest
themselves in the operations of this system. Thus
' it is highly probable that the sympathetic division,
because arranged for diffuse discharge, is likely
to be brought into activity as a whole, whereas
the sacral and cranial divisions, arranged for
particular action on separate organs, may operate
, in parts. Also, because antagonisms exist be-
^' tween the middle and either end division of the
autonomic, affective states may be classified ac-
cording to their expression in the middle or an
end division and these states would be, like the
nerves, antagonistic in character. And finally,
since the adrenal glands are innervated by au-
tonomic fibres of the mid-division, and since ad-
renal secretion stimulates the same activities that
are stimulated nervously by this division, it is
possible that disturbances in the realm of the
sympathetic, although initiated by nervous dis-
charge, are .automatically augmented and pro-
longed through chemical effects of the adrenal
secretion.

EEFEEENCES

1 Cannon : The American Journal of Psychology, 1914,
XXV, p. 257.

VISCERAL NERVES 39

" For a summary of his studies of the organization of the
autonomic system, see Langley: Ergebnisse der Physiologie,
Wiesbaden, 1903, ii^, p. 818.

^ See Cannon : American Journal of Physiology, 1905,
xiii, p. xxii.

* See Sherrington : The Integrative Action of the Nerv-
ous System, New York, 1909, p. 19.

° Langley and Anderson : Journal of Physiology, 1895,
xix, see pp. 85, 122.

^Sherrington: Loc. cit., p. 90.

■^ Elliott : Journal of Physiology, 1905, xxxii, p. 426.

* See Elliott : Journal of Physiology, 1913, xlvi, p. 289 ff.

CHAPTEE III

METHODS OF DEMONSTEATING ADEENAL
SECEETION AND ITS NEEVOUS CONTEOL

As stated in the first chapter, the inhibition of
gastric secretion produced by great excitement
long outlasts the presence of the object which'
evokes the excitement. The dog that was en-
raged by seeing a cat for five minutes secreted
only a few drops of gastric juice during the next
fifteen minutes. Why did the state of excitation
persist so long after the period of stimulation had
ended? This question, which presented itself to
me while reading Bickel and Sasaki's paper, fur-
nished the suggestion expressed at the close of
the last chapter, that the excitement might pro-
voke a flow of adrenal secretion, and that the
changes originally induced in the digestive organs
by nervous impulses might be continued by circu-
lating adrenin. The prolongation of the effect
might be thus explained. Whether that idea is
correct or not has not been tested. Its chief serv-
ice was ia leading to an enquiry as to whether

40

ADEENAL SECEETION 41

the adrenal glands are in fact stimulated to action
in emotional excitement. The preganglionic fibres
passing to the glands are contained in the splanch-
nic nerves. What is the effect of splanchnic stim-
ulation?

The Evidence that Splanchnic Stimulation Induces
Adrenal Secretion

It was in 1891 that Jacobi ^ described nerve
fibres derived from the splanchnic trunks which
were distributed to the adrenal glands. Six years
later BiedP found that these nerves conveyed
vaso-dilator impulses to the glands, and he sug-
gested that they probably conveyed also secre-
tory impulses. Evidence in support of this sug-
gestion was presented the following year by
Dreyer,^ who demonstrated that electrical ex-
citation of the splanchnic nerves produced in the
blood taken from the adrenal veins an increased
amount of a substance having the power of rais-
ing arterial blood pressure, and that this result
was independent of accompanying changes in the
blood supply to the glands. The conclusion drawn
by Dreyer that this substance was adrenin has
been confirmed in various ways by later observers.
Tscheboksaroff * repeated Dreyer's procedure
and found in blood taken from the veins after
splanchnic stimulation evidences of the presence
of adrenin that were previously absent. Asher ®

42 BODILY CHANGES

observed a rise of blood pressure when tbe glands
were stimulated in such, a ma-nner as not to cause
constriction of the arteries — the rise was there-
fore assumed to be due to secreted adrenin.
Dilation of the pupil was used by Meltzer and
Joseph « to prove secretory action of the splanch-
nics on the adrenal glands ; they found that stim-
ulation of the distal portion of the cut splanchnic
nerve caused the pupil to enlarge— an effect char-
acteristic of adrenin circulating in the blood.
Elliott '^ repeated this procedure, but made it
a more rigorous proof of internal secretion of the
adrenals by noting that the effect failed to ap-
pear if the gland on the stimulated side was re-
moved. Additional proof was brought by myself
and Lyman * when we found that the typical
drop in arterial pressure produced in cats by in-
jecting small amounts of adrenin could be ex-
actly reproduced by stimulating the splanchnic
nerves after the abdominal blood vessels, which
contract when these nerves are excited, were tied
so that no changes iu them could occur to in-
fluence the rest of the circulation.

The problem of splanchnic influence on the ad-
renal glands Elliott attacked by a still different
method. Using, as a measure, the graded effects
of graded amounts of adrenin on blood pressure,
he was able to assay the quantity of adrenin in
adrenal glands after various conditions had been

ADEENAL SECEETION 43

allowed to prevail. The tests were made on cats.
In these animals each adrenal gland is supplied
only by the splanchnic fibres of its own side, and
the two glands normally contain almost exactly the
same amount of adrenin. Elliott ^ found that
when the gland on one side was isolated by cutting
its splanchnic supply, and then impulses were sent
along the intact nerves of the other side, either
by disturbing the animal or by artificial excita-
tion of the nerves, the gland to which these fibres
reached invariably contained less adrenin, often
very much less, than the isolated gland. Results
obtained by the method employed by Elliott have
been confirmed with remarkable exactness in re-
sults obtained by Folin, Denis and myself,^"
using a highly sensitive color test after adding
the gland extract to a solution of phosphotungstic
acid.

All these observations, with a variety of meth-
ods, and by a respectable number of reliable in-
vestigators, are harmonious in bringing proof
that artificial stimulation of the nerves leading
to the adrenal glands will induce secretory ac-
tivity in the adrenal medulla, and that in conse-
quence adrenin will be increased in the blood.
The fact is therefore securely established that in
the body a mechanism exists by which these
glands can be made to discharge this peculiar sub-
stance promptly into the circulation.

44 BODILY CHANGES

The Question of Adrenal Secretion in Emotional
Excitement

As we have already seen, the phenomena of a
great emotional disturbance in an animal indi-
cate that sympathetic impulses dominate the vis-
cera. When, for example, a cat becomes fright-
ened, the pupils dilate, the activities of the
stomach and intestines are inhibited, the heart
beats rapidly, the hairs of the back and tail stand
erect — from one end of the ailimal to the other
there are abundant signs of nervous discharges
along sympathetic courses. Do not the adrenal
glands share in this widespread subjugation of
the viscera to sympathetic control?

This question, whether the common excitements
of an animal's life might be capable of evoking
a discharge of adrenin, was taken up by D. de la
Paz and myself in 1910. "We made use of the nat-
ural enmity between two laboratory animals, the
dog and the cat, to pursue our experiments. In
these experiments the cat, fastened in a comfor-
table holder (the holder already mentioned as be-
ing used in X-ray studies of the movements of
the alimentary canal), was placed near a barking
dog. Some cats when thus treated showed al-
most no signs of fear; others, with scarcely a
movement of defence, presented the typical pic-
ture. In favorable cases the excitement was al-
lowed to prevail for five or ten minutes, and in

ADRENAL SECRETION 45

a few cases longer. Samples of blood were taken
within a few minutes before and after tbe period.

The Method of Securing Blood from Near the Adrenal

Veins

The blood was obtained from the inferior vena
cava anterior to the opening of the adrenal veins,
i. e., at a point inside the body near the level of
the notch at the lower end of the sternum. To
get the blood so far from the surface without
disturbing the animal was at first a difficult prob-
lem. We found, however, that by making anes-
thetic with ethyl chloride the skin directly over
the femoral vein high in the groin, the vein could
be quickly bared, cleared of connective tissue,
tied, and opened without causing any general dis-
turbance whatever. A long, fine, flexible catheter
(2.4 millimeters in diameter) which had pre-
viously been coated with vaseline inside and out,
to lubricate it and to delay the clotting of blood
within it, was now introduced into the opening in
the femoral vein, thence through the iliac and
on into the inferior cava to a point near the level
of the sternal notch. A thread tied around this
tube where, after being inserted to the proper dis-
tance, it disappeared into the femoral vein,
marked the extent of insertion, and permitted a
later introduction to the same extent. This slight
operation — a venesection, commonly practised on

46 BODILY CHANGES

our ancestors — consumed only a few minutes, and
as the only possibility of causing pain was
guarded against by local anesthesia, the animal
remained tranquil throughout. Occasionally it
was necessary to stroke the cat's head gently to
keep her quiet on the holder, and under such cir-
cumstances I have known her to purr during all
the preparations for obtaining the blood, and
while the blood was being taken.

The blood (3 or 4 cubic centimetres) was slowly
drawn through the catheter into a clean glass
syringe. Care was taken to avoid any marked
suction such as might cause collapse of the vein
near the inner opening of the tube. As soon as
the blood was secured, the catheter was removed
and the vein tied loosely, to prevent bleeding.
The blood was at once emptied into a beaker, and
the fibrin whipped from it by means of fringed
rubber tubing fitted over a glass rod. Since this
defibrinated blood was obtained while the ani-
mal was undisturbed, it was labelled "quiet
blood."

The animal was then exposed to the barking
dog, as already described, and immediately there-
after blood was again removed, from precisely
the same region as before. This sample, after
being defibrinated, was labelled "excited blood."
The two samples, the "quiet" and the "excited,"
both obtained in the same manner and subse-

ADRENAL SECRETION 47

quently treated in the same manner, were now
tested for their content of adrenin.

The Method op Testing the Blood for Adrenin

It was desirable to use as a test tissues to
which the blood was naturally related. As will
be recalled, adrenin affects viscera even after
they have been removed from the body, just as if
they were receiving impulses via sympathetic
fibres, and further, that sympathetic fibres nor-
mally deliver impulses which cause contraction
of the internal genitals and relaxation of the
stomach and intestines. The uterus has long been
employed as a test for adrenin, the presence of
which it indicates by increased contraction. That
isolated strips of the longitudinal muscle of the
intestine, which are contracting rhythmically, are
characteristically inhibited by adrenin in dilu-
tions of 1 part in 20 millions, had been shown by
Magnus in 1905. Although, previous to our in-
vestigation in 1910, this extremely delicate reac-
tion had not been used as a biological signal for
adrenin, it possesses noteworthy advantages over
other methods. The intestine is found in all ani-
mals and not in only half of them, as is the uterus ;
it is ready for the test within a few minutes, in-
stead of the several hours said to be required for
the best use of the uterus preparation;" and it
responds by relaxing. This last characteristic

48 BODILY CHANGES

is especially important, for in defibrinated blood
there are, besides adrenin, other substances cap-
able of causing contraction of smooth muscle,"
and liable therefore to lead to erroneous con-
clusions when a structure which responds by con-
tracting, such as uterus or artery, is used to prove
whether adrenin is present. On the other hand,
substances producing relaxation of smooth muscle
are few, and are unusual in blood.^*

We used, therefore, the strip of intestinal mus-
cle as an indicator. Later Ho skins ^* modified
our procedure by taking, instead of the strip, a
short segment of the rabbit intestine. The seg-
ment is not subjected to danger of injury during
its preparation, and when fresh it is almost in-
credibly sensitive. It may be noticeably inhibited
by adrenin, 1 part in 200 millions!

The strip, or the intestinal segment, was sus-
pended between minute wire pincers {serres
fines) in a cylindrical chamber 8 millimeters in
diameter and 5 centimeters deep. By a thread
attached to the lower serre fime the preparation
was drawn into the chamber, and was held firmly ;
by the upper one it was attached to the short end
of a writing lever (see Fig. 2). When not ex-
posed to blood, the strip was immersed in a nor-
mal solution of the blood salts (Einger's). The
blood or the salt solution could be quickly with-
drawn from or introduced into the chamber, with-

ADRENAL SECRETION

49

out disturbing the muscle, by means of a fine
pipette passed down along the inner surface. The
chamber and its contents, the stock of Ringer's

Figure 2. — Diagram of the arrangements for recording con-
tractions of the intestinal muscle.

solution, and the samples of "quiet" and "ex-
cited" blood were all surrounded by a large vol-
ume of water kept approximately at body tem-
perature (37° C). Through the blood or the salt
solution in the chamber oxygen was passed in a
slow but steady stream of bubbles. Under these
circumstances the strip will live for hours, and
will contract and relax in a beautifully regular
rhythm, which may be recorded graphically by
the writing lever.

The first effect of surrounding the muscle with
blood, whether "quiet" or "excited," was to send
it into a strong contraction which might persist,
sometimes with slight oscillations, for a minute
or two (see Figs. 4 and 5). After the initial short-
ening, the strip, if in quiet blood soon began to

50 BODILY CHANGES

contract and relax rhythmically and with each re-
laxation to lengthen more, until a fairly even
base line appeared in the written record. At this
stage the addition of fresh "quiet" blood usually
had no effect, even though the strip were washed
once with Einger's solution before the second por-
tion of the blood was added. For comparison of
the effects of "quiet" and "excited" blood on the
contracting strip, the two samples were each
added to the muscle immediately after the Eing-
er's solution had been removed, or they were ap-
plied to the muscle alternately and the differences
in effect then noted. The results obtained by
these methods are next to be presented.

EEFEEENCES

1 Jacobi : Archiv f iir experimentelle Pathologie und Phar-
makologie, 1891, xxix, p. 185.

^ Biedl : Archiv f iir die gesammte Physiologie, ISOY, Ixvii,
pp. 456, 481.

^ Dreyer : American Journal of Physiology, 1898-99, ii,
p. 219.

* Tscheboksaroff : Archiv f iir die gesammte Physiologie,
1910, cxxxvii, p. 103.

^ Asher : Zeitschrift f iir Biologie, 1912, Iviii, p. 274.

*> Meltzer and Joseph : American Journal of Physiology,

1912, xxix, p. xxxiv.

^Elliott: Journal of Physiology, 1912, xliv, p. 400.

' Cannon and Lyman : American Journal of Physiology,

1913, xxxi, p. 377.

" Elliott : Journal of Physiology, 1912, xliv, p. 400.
^^ Eolin, Cannon and Denis : Journal of Biological Chem-
istry, 1913, xiii, p. 477.

ADEENAL SECRETION 51

^'^ Fraenkel : Archiv f iir experimentelle Pathologie und
Pharmakolog-ie, 1909, Ix, p. 399.

^^ See O'Connor : Archiv fiir die experimentelle Patholo-
gie und Pharmakologie, 1912, Ixvii, p. 206.

^' Grutzner : Ergebnisse der Physiologie, 1904, iii^, p. 66 ;
Magnus: Loc. cit., p. 69.

^*Hoskins: Journal of Pharmacology and Experimental
Therapeutics, 1911, iii, p. 95.

CHAPTER IV

ADEENAL SECRETION IN STEONG EMOTIONS
AND PAIN

If the secretion of adrenin is increased in strong
emotional states and in pain, that constitutes a
fact of considerable significance, for, as already
mentioned, adremn is capable of_grodncing many
IJf of the bodily changes which are characteristically
manifested in emotional and painful experiences,
rt is a matter of prime importance for further
discussion to determine whether the adrenal
glands are in fact roused to special activity in
times of stress.

The Evidence that Adrenal Secretion Is Increased in
Emotional Excitement

That blood from the adrenal veins causes the
relaxation of intestinal muscle characteristic of
adrenal extract or adrenin is shown in Fig. 3.
The muscle was originally beating in blood which
contained no demonstrable amount of adrenal se-
cretion ; this inactive blood was replaced by blood

52

ADRENAL SECRETION IN EMOTIONS 53

from the adrenal veins, obtained after quick
etherization. Etherization, it will be recalled, is
accompanied by a "stage of excitement." Re-
laxation occurred almost immediately (at b).
Then the rhythm was renewed in the former

FiGtTBB 3. — ^Intestinal muscle beat-
ing in inactive blood, which was with-
drawn from the chamber at a. Blood
from the adrenal vein of an animal ex-
cited by etherization was substituted
at b, and withdrawn at c. Contrac-
tions were restored in the original in-
active blood which was removed at d.
Blood from the renal vein (same ani-
mal) was added at e.

In this and subsequent records time
is marked in half minutes.

blood, and thereupon the muscle was surrounded
with blood from the vein leading away from the
left kidney, i. e., blood obtained from the same
animal and under the same conditions as the
adrenal blood, but from a neighboring vein. No
relaxation occurred. By this and other similar
tests the reliability of the method was proved.

54 BODILY CHANGES

In no instance did blood from the inferior vena
cava of the quiet normal animal produce relaxa-
tion. On the other hand, blood from the animal
after emotional excitement showed more or less
promptly the typical relaxation. In Fig. 4 is

Figure 4. — Alternate application of "excited" blood (at 6
and/) and "quiet" blood (at d), from the same animal, to in-
testinal muscle initially beating in Ringer's solution.

represented the record of intestinal muscle which
was beating regularly in Einger's solution. At a
the Einger's solution was removed, and at b "ex-
cited" blood was added; after the preliminary
shortening, which, as already stated, occurs at
the first immersion in blood, the muscle length-
ened gradually into complete inhibition. At c the
"excited" blood was removed, and at d "quiet"
blood was added in its place. The muscle at once
began, fairly regular rhythmic beats. At e the
"quiet" blood was removed, and at / the "excited"
blood was again applied. The muscle lengthened
almost immediately into an inhibited state. In
this instance the "excited" blood was taken after

ADEENAL SECEETION IN EMOTIONS 55

the eat had been barked at for about fifteen min-
utes.

The increase of effect with prolongation of the
period of excitement is shown in Fig. 5. A is the

Figure 5. — The effect of prolonging the excitement. A, the
record in "quiet" serum; B, in defibrinated blood after eleven
minutes of excitement; and C, in serum after fifteen minutes of
excitement.

record of contractions after the muscle was sur-
rounded with "quiet" blood serum. B shows the
gradual inhibition which occurred when the mus-
cle was surrounded with defibrinated blood taken
when the animal had been excited eleven minutes.
And C is the record of rapid inhibition after fif-
teen minutes of excitement. In other instances
the effect was manifested merely by a lowering
of the tonus of the muscle, and a notable slowing
of the beats, without, however, a total abolition
of them.

The inference that this inhibition of contrac-
tion of the intestinal muscle is due to an increased
amount of adrenal secretion in the "excited"

56

BODILY CHANGES

blood de la Paz and I justified on several grounds :
(1) The inhibition was produced by "excited"
blood from the inferior vena cava anterior to the
mouths of the adrenal veins, when blood from the
femoral vein, taken at the same time, had no in-
hibitory influence. Since blood from the femoral
vein is typical of the cava blood below the en-
trance of the kidney veins, the conclusion is war-
ranted that the difference of effect of the two
samples of blood is not due to any agent below
the kidneys. But that blood from the kidneys
does not cause the relaxation is shown in Fig. 3.

FiGTJRB 6. — Failure of the cava blood
(added at a) to produce inhibition when
excitement has occurred after removal
of the adrenal glands. The muscle later
proved sensitive to adrenin in blood in
the ratio 1:1,000,000.

The only other structures which could alter the
blood between the two points at which it was
taken are the adrenal glands, and the material

ADEENAL SECEETION IN EMOTIONS 57

secreted by them would produce precisely the
inhibition of contraction which was in fact pro-
duced.

(2) If in ether anesthesia the blood vessels
leading to and from the adrenal glands are first
carefully tied, and then the glands are removed, ex-

FiGURE 7.— Effect of adding adrenin 1 :1,000,000 (A), 1 :2,000,000
(B), and 1:3,000,000 (C), to formerly inactive blood. In each case
a marks the moment when the quiet blood was removed, and 6, the
time when the blood with adrenin was added.

citement four or five hours later, before the weak-
ness that follows the removal has become promi-
nent, does not alter the blood so that the typical
inhibition occurs (see Fig. 6). Thus, although
the animal shows all the characteristic signs of
sympathetic stimulation, the blood, in the absence
of the adrenals, remains unchanged.

(3) As already shown, sometimes the effect pro-

68 BODILY CHANGES

duced by the "excited" blood was prompt inbibi-
tion, sometimes tbe inhibition followed only after
several beats, and sometimes a slowing and short-
ening of contractions, with a lower tone, were the
sole signs of the action of adrenin. All these
degrees of relaxation can be duplicated by adding
to inactive blood varying amounts of adrenin.
Fig. 7 shows the effects, on a somewhat insensi-
tive muscle preparation, of adding adrenin,
1:1,000,000 (A), 1:2,000,000 (B), and 1:3,000,000
(C), to different samples of blood joreviously with-
out inhibitory influence. These effects of adrenin
and the effects produced by blood taken near the
opening of the adrenal veins are strikingly analo-
gous.

(4) Emden and v. Furth ^ have reported that
0.1 gram of suprarenin chloride disappears almost
completely in two hours if added to 200 cubic
centimeters of defibrinated beef blood, and the
mixture constantly aerated at body temperature.
"Excited" blood which produces inhibition loses
that power on standing in the cold for twenty-four
hours, or on being kept warm and agitated with
bubbling oxygen. This change is illustrated in
Fig. 8 ; the power of the "excited" blood to inhibit
the contractions of the intestinal muscle when rec-
ord A was written was destroyed after three
hours of exposure to bubbling oxygen, as shown
by record B. The destruction of adrenin and

ADRENAL SECRETION IN EMOTIONS 59

the disappearance of the effect which adrenin
would produce are thus closely parallel.

All these considerations, taken with the proof

Figure 8.— The effect of bubbling
oxygen through active blood. A, re-
laxation after active blood applied at
a; B, failure of relaxation when the
same blood, oxygenated three hours,
was appHed to a fresh strip at b.

that sympathetic impulses increase secretion of the
adrenal glands, and taken also with the evidence
that, during such emotional excitement as was em-
ployed in these experiments, signs of sympathetic
discharges appeared throughout the animal from
the dilated pupil of the eye to the standing hairs
of the tail-tip, led us to the conclusions that the
characteristic action of adrenin on intestinal mus-
cle was in fact, in our experiments, due to secre-
tion of the adrenal glands, and that that secretion
is increased in great emotion.

The Evidence that Adrenal Secretion is Increased by

"Painful" Stimulation

As mentioned in the first chapter, stimulation of
sensory fibres in one of the larger nerve trunks

60 BODILY CHANGES

is known to result in such nervous discliarges along
sympathetic paths as to produce marked inhibi-
tion of digestive processes. Other manifestations
of sympathetic innervations — e. g., contraction of
arterioles, dilation of pupils, erection of hairs —
are also demonstrable. And since the adrenal
glands are stimulated to activity by sympathetic
impulses, it was possible that they would be af-
fected as are other structures supplied with sym-
pathetic fibres, and that they would secrete in
greater abundance when sensory nerves were irri-
tated.

The testing of this possibility was undertaken by
Hoskins and myself in 1911. Since bodily changes
from "painful" stimulation can in large degree be
produced in an anesthetized animal, without, how-
ever, an experience of pain by the animal, it was
possible to make the test quite simply. The sen-
sory stimulus was a rapidly interrupted induced
current applied to the sciatic nerve. The current
was increased in strength as time passed, and thus
the intensity of the effect, indicated by continuous
dilation of the pupils, was maintained. There was
no doubt that such stimulation would have caused
very severe pain if the animal had not been anes-
thetized. Indeed, the stimulus used was probably
much stronger than would be necessary to obtain
a positive result in the absence of the anesthetic
(urethane), which markedly lessens the irritabil-

ADEENAL SECEETION IN EMOTIONS 61

ity of visceral nerve fibres.^ In different in-
stances the stimulation lasted from three to six
minutes. Throughout the period there was mark-
edly increased rapidity and depth of breathing.
As Fig. 9 shows, the normal blood, removed

FiGXTEB 9. — Intestinal mus-
cle beating in normal vena cava
blood, removed at 1 and re-
newed at 2. At 3 normal blood
removed. At 4 contraction in-
hibited by vena cava blood
drawn after sensory stimula-
tion; at 5 removed. At 6 Rin-
ger's solution substituted.

62 BODILY CHANGES

from the vena cava before stimulation, caused no
inhibition of the beating segment, whereas that
removed afterwards produced a deep relaxation.
Hoskins and I showed that the increased respira-
tion which accompanies "painful" stimulation does
not augment adrenal activity. We concluded,
therefore, that when a sensory trunk is strongly
excited the adrenal glands are reflexly stimulated,
and that they pour into the blood stream an in-
creased amount of adrenin.

Confirmation of Ocr Eesults by Other Observers

The foregoing experiments and conclusions were
reported in 1911. In 1912, Elliott * brought con-
firmatory evidence by use of a method quite differ-
ent from ours. As previously stated, he studied
the effects of experimental procedures on adrenal
secretion by a careful comparative quantitative
assay of the adrenin content of the glands when
one gland was isolated from the central nervous
system and the other left connected. He took
advantage of the action of morphia and of the
substance B-tetrahydronaphthylamine in evoking
in cats all the appearances of great fright. After
the animals had thus been "frightened," he found
that the adrenal gland which was still connected
with the spinal cord was much depleted of its
adrenin content compared with the other, isolated
gland. And he observed, further, that animals

ADEENAL SECEETION IN EMOTIONS 63

newly brought to the laboratory, and evidently
disturbed by the strangeness of their surroundings,
had a considerably smaller amount of adrenin in
their glands than other animals grown accustomed
to the situation. Elliott also observed that pro-
longed excitation of a sensory nerve, such as the
great sciatic, may cause the adrenin largely to
disappear from the gland still connected with the
central nervous system and subjected, therefore, to
reflex influences.

Our conclusions have also been confirmed more
recently (1913) by Hitchings, Sloan and Austin,*
working in Crile's laboratory in Cleveland. They
used the same method which we had used to ob-
tain blood and to test for adrenin, and found that
after great fear and rage had been induced in a
cat by the attempt of a muzzled dog to fight it,
the adrenin reaction was clearly demonstrable.
And just as we had noted that the reaction did not
occur if the adrenal glands had been removed, they
showed that it did not occur if the nervous connec-
tions with the spinal cord were previously severed.

The logic of all these experiments may be briefly
summed up. That the adrenal glands are subject
to splanchnic influence has been demonstrated
anatomically and by the physiological effects of
their secretion after artificial stimulation of the
splanchnic nerves. Impulses are normally sent
along these nerves, in the natural conditions of

64 BODILY CHANGES

life, when animals become greatly excited, as in
fear and rage and pain. There is every probabil-
ity, therefore, that these glands are stimulated to
extra secretion at such times. Both by an ex-
ceedingly delicate biological test (intestinal mus-
cle) and by an examination of the glands them-
selves, clear evidence has been secured that in pain
and deep emotion the glands do, in fact, pour out
an excess of adrenin into the circulating blood.

Here, then, is a remarkable group of phenomena
— a pair of glands stimulated to activity in times
of strong excitement and by such nerve impulses
as themselves produce at such times profound
changes in the viscera ; and a secretion given forth
into the blood stream by these glands, which is
capable of inducing by itself, or of augmenting,
the nervous influences which induce the very
changes in the viscera which accompany suffering
and the major emotions. What may be the sig-
nificance of these changes, occurring when condi-
tions of pain and great excitement — experiences
common to animals of most diverse types and
probably known to their ancestors for ages past
— lay hold of the bodily functions and determine
the instinctive responses ?

Certain remarkable effects of injecting adrenin
into the blood have for many years been more or
less well recognized. For example, when injected
it causes liberation of sugar from the liver into

ADRENAL SECRETION IN EMOTIONS 65

the blood stream. It relaxes the smooth, muscle
of the bronchioles. Some old experiments indi-
cated that it acts as an antidote for muscular
fatigue. It alters the distribution of the blood in
the body, driving it from the abdominal viscera
into the heart, lungs, central nervous system and |
limbs. And there was some evidence that it ren-
ders more rapid the coagulation of the blood.
There may be other activities of adrenin not yet
discovered — it may co-operate with the products
of other glands of internal secretion. And other
glands of internal secretion may be stimulated by
sympathetic impulses. But we were not concerned
with these possibilities. We wished to know
whether the adrenin poured out in pain and emo-
tional excitement produced or helped to produce

the same effects that follow the injection of adre-

nin. Our later researches were concerned with an-
swers to this question.

EEFEEENCES

' Embden and v. Eurtli : Hofmeister's Beitrage zur
chemischen Physiologie und Pathologie, 1904, iv, p. 423.

2 Elliott : Journal of Physiology, 1905, xxxii, p. 448.

3 Elliott : Journal of Physiology, 1912, xliv, p. 409.

*Hitchings, Sloan and Austin: Cleveland Medical Jour-
nal, 1913, xii, p. 686; see also Crile and Lower: Anoci-asso-
ciation, Philadelphia, 1914, p. 56.

CHAPTEE V

THE INCEEASE OF BLOOD SIJGAE IN PAIN
AND GREAT EMOTION

Sugar is the form in which carbohydrate mate-
rial is transported in organisms ; starch is the stor-
age form. In the bodies of animals that have
been well fed the liver contains an abundance of
glycogen or "animal starch," which may be called
upon in times of need. At such times the glycogen
is changed, and set free in the blood as sugar.
Ordinarily there is a small percentage of sugar
in the blood — from 0.06 to 0.1 per cent. When
only this small amount is present the kidneys are
capable of preventing its escape in any noteworthy
amount. If the percentage rises to the neighbor-
hood of 0.2-0.3 per cent, however, the sugar passes
the obstacle set up by the kidneys, and is readily
demonstrable in the urine by ordinary tests. The
condition of "glycosuria," therefore, may prop-
erly be considered, in certain circumstances, as
evidence of increased sugar in the blood. The in-
jection of adrenin can liberate sugar from the

66

INCEEASE OF BLOOD SUGAE 67

liver to sucli an extent that glycosuria results.
Does the adrenal secretion discharged in pain and
strong emotional excitement play a role in pro-
ducing glycosuria under such conditions?

In clinical literature scattered suggestions are
to be found that conditions giving rise to emo-
tional states may be the occasion also of more or
less permanent glycosuria. Great grief and pro-
longed anxiety during a momentous crisis have
been regarded as causes of individual instances
of diabetes, and anger or fright has been followed
by an increase in the sugar excreted by persons
who already have the disease. Kleen ^ cites
the instance of a German officer whose diabetes
and whose Iron Cross for valor both came from
a stressful experience in the Franco-Prussian War.
The onset of the disease in a man directly after
his wife was discovered in adultery is described
by Naunyn;^ and this author also mentions
two cases in his own practice — one started during
the bombardment of Strassburg (1870), the other
started a few days after a companion had shot
himself. In cases of mental disease, also, states
of depression have been described accompanied
by sugar in the urine. Schultze^ has reported
that in these cases the amount of glycosuria is de-
pendent on the degree of depression, and that the
greatest excretion of sugar occurs in the fear-
psychoses. Eaimann * has reported that in both

68 BODILY CHANGES

melancholia and mania the assimilation limit of
sugar may be lowered. Similar results in the
insane have recently been presented by Mita,^
and by Folin and Denis.« The latter investiga-
tors found glycosuria in 12 per cent of 192 insane
patients, most of whom suffered from depression,
apprehension, or excitement. And Arndt '' has
observed glycosuria appearing and disappearing
as alcoholic delirium appeared and disappeared in
his patients.

Although clinical evidence thus indicates an
emotional origin of some cases of diabetes and
glycosuria, the intricacies of existence and the
complications of disease in human beings throw
some doubt on the value of that evidence. Both
Naunyn * and Hirschfeld, although mentioning
instances of diabetes apparently due to an emo-
tional experience, urge a skeptical attitude to-
ward such statements. It is desirable, therefore,
that the question of an emotional glycosuria be
tested under simpler and more controllable con-
ditions. "Emotional glycosuria" in experimental
animals has indeed been referred to by Water-
man and Smit * and more recently by Hender-
son and Underhill.i" Both these references, how-
ever, are based on the work of Bohm and Hoff-
mann,^^ reported in 1878.

INCREASE OF BLOOD SUGAR 69

Glycosuria From Pain

Bohm and Hoffmann found that cats, when
bound to an operating board, a tube inserted into
the trachea (without anesthesia), and in some
instances a catheter inserted into the urethra
through an opening above the pubis, had in about
half an hour an abundance of sugar in the urine.
In three determinations sugar in the blood proved
slightly above "normal" so long as sugar was ap-
pearing in the urine, but returned to "normal"
as the glycosuria disappeared. Since they were
able to produce the phenomenon by simply bind-
ing animals to the holder, they called it "Fes-
selungsdiabetes."

As possible causes af this glycosuria in bound
animals, they considered opening the trachea,
cooling, and pain. The first two they readily
eliminated, and still they found sugar excreted.
Pain they could not obviate, and since, without
binding the animals, they caused glycosuria by
merely stimulating the sciatic nerves, they con-
cluded that painful confinement was itself a suffi-
cient cause. Other factors, however, such as cool-
ing and circulatory disturbances, probably co-
operated with pain, they believed, to produce the
result. Their observations on cats have been
proved true also of rabbits ;i2 and recently it has
been shown that an operation involving some pain
increases blood sugar in dogs.^^ Temporary gly-

70 BODILY CHANGES

cosuria has likewise been noted in association with
intense pain in human beings.

Inasmuch as Bohm and Hoffmann did not men-
tion the emotional element in discussing their re-
sults, and inasmuch as they admitted that they
could not obviate from their experimental pro-
cedure pain, which they themselves proved was
effective in causing glycosuria, desig-nating what
they called "Fesselungsdiabetes" as "emotional
glycosuria" is not justified.

Emotional Glycosuria

The discovery that during strong emotion adre-
nal secretion is increased, and the fact that injec-
tion of adrenin gives rise to glycosuria, suggested
that glycosuria might be called forth by emotional
excitement, and then that even without the painful
element of Bohm and Hoffmann's experiments,
sugar might be found in the urine. The testing of
this possibility was undertaken by A. T. Shohl, W.
S. Wright and myself in 1911.

Our first procedure was a repetition of Bohm
and Hoffmann's experiments, freed from the
factor of pain. The animals (cats) were bound
to a comfortable holder, which left the head
unfastened. This holder I had used hundreds
of times in X-ray studies of digestion, with
many different animals, without causing any signs
of even so much as uneasiness. Just as in obser-

INCEEASE OF BLOOD SUGAE 71

vations on the movements of ttie alimentary canal,
however, so here, the animals reacted differently
to the experience of being confined. Young males
usually became quite frantic, and with eyes wide,
pupils dilated, pulse accelerated, hairs of the tail
more or less erect, they struggled, snarling and
growling, to free themselves. Females, on the
contrary, especially if elderly, were as a rule
much more calm, and resignedly accepted the novel
situation.

According to differences in reaction the animals
were left in the holder for periods varying in
length from thirty minutes to five hours. In
order to insure prompt urination, considerable
quantities of water were given by stomach tube
at the beginniag of the experiment and in some
cases again later. Arrangements were made for
draining the urine promptly, when the animal was
on the holder or when afterwards in a metal metab-
olism cage, into a glass receiver containing a few
drops of chloroform to prevent fermentation.
The diet in all cases consisted of customary raw
meat and milk. In every instance the urine was
proved free from sugar before the animal was
excited.

In our series of observations twelve cats were
used, and in every one a well-marked glycosuria
was developed. The shortest periods of confine-
ment to the holder which were effective were thirty

72 BODILY CHANGES

and forty minutes ; the longest we employed, five
hours. The average time required to bring about
a glycosuria was less than an hour and a half;
the average in seven of the twelve cases was less
than forty minutes. In all eases no sugar was
found in the urine passed on the day after the
excitement.

The promptness with which the glycosuria de-
veloped was directly related to the emotional state
of the animal. Sugar was found early in animals
which early showed signs of being frightened
or in a rage, and much later in animals which took
the experience more calmly.

As cooling may result in increased sugar in the
blood, and consequent glycosuria, the rectal tem-
perature was observed from time to time, and it
was found to vary so slightly that in these experi-
ments it was a wholly negligible factor. In one
cat the rectal temperature fell to 36° C. while the
animal was bound and placed in a cold room (about
2° C.) for fifty minutes, but no sugar appeared in
the urine.

Further evidence that the appearance of sugar
in the urine may arise purely from emotional ex-
citement was obtained from three cats which gave
negative results when bound in the holder for
varying periods up to four hours. It was note-
worthy that these animals remained calm and
passive in their confinement. When, however,

INCREASE OF BLOOD SUGAR 73

they were placed, separately, in a small wire cage,
and were barked at by an energetic little dog, that
jumped at them and made signs of attack, the cats
became much excited, they showed their teeth,
humped their backs, and growled defiance. This
sham fight was permitted to continue for a half
hour in each of the three cases. In each case the
animal, which after four hours of bondage had ex-
hibited no glycosuria, now had sugar in the urine.
Pain, cooling, and bondage were not factors in
these experiments. The animal was either fright-
ened or enraged by the barking dog, and that ex-
citement was attended by glycosuria.

The sugar excreted in the twenty-four hours
which included the period of excitement was de-
termined by the Bertrand method.^* It ranged
from 0.024 gram to 1.93 grams, or from 0.008
gram to 0.62 gram per kilo body weight, for the
twenty-four hours' quantity.

The presence of sugar in the urine may be used
as an indication of increased sugar in the blood,
for unless injury has been done to the cells of
the kidneys, they do not permit sugar to escape
imtil the percentage in the blood has risen to a
considerable degree. Thus, though testing the
urine reveals the instances of a high content of
blood sugar, it does not show the fine variations
that appear when the blood itself is examined.
Recently Scott ^^ has concluded a thorough in-

74 BODILY CHANGES

vestigation of the variations of blood sugar in cats,
and has found that merely incidental conditions,
producing even mild excitement, as indicated by
crying or otherwise, result in a noticeable rise in
the amount. Indeed, so sensitive is the sugar-lib-
erating mechanism that all the early determina-
tions of the "normal" content of sugar in blood
which has been drawn from an artery or vein in
the absence of anesthesia, are of very doubtful
value. Certainly when care is taken to obtain
blood suddenly from a tranquil animal, the per-
centage (0.069, Scott; 0.088, Pavy) is much less
than when the blood is drawn without anesthesia
(0.15, Bohm and Hoffmann), or after light nar-
cosis (0.282, Bona and Takahashi").

Our observations on eats have since been found
valid for rabbits. EoUy and Oppermann, Jacob-
sen, and Hirseh and Eeinbach ^'^ have recently
recorded that the mere handling of a rabbit pre-
paratory to operating on it will increase the per-
centage of blood sugar (in some cases from 0.10
to 0.23 and 0.27 per cent). Dogs are said to be
much less likely to be disturbed by the nature of
their surroundings than are rabbits and cats.
Nevertheless, pain and excitement are such funda-
mental experiences in animals that without much
doubt the same mechanism is operative in all when
these experiences occur. Probably, just as the
digestion of dogs is disturbed by strong emotion,

INCEEASE OF BLOOD SUGAE 75

the blood sugar likewise is increased, for sym-
pathetic impulses occasion both changes.* Gib
has given an account of a bitch that became much
agitated when shut up, and after such enforced
seclusion, but never otherwise, she excreted small
quantities of sugar in the urine.^^

The results noted in these lower animals have
been confirmed in human beings. One of my for-
mer students, W. G. Smillie, found that four of
nine medical students, all normally without sugar
in their urine, had glycosuria after a hard exami-
nation, and only one of the nine had glycosuria
after an easier examination. The tests, which
were positive with Fehling's solution, Nylander's
reagent, and also with phenyl-hydrazine, were
made on the first urine passed after the exam-
ination. Furthermore, 0. H. Fiske and I ex-
amined the urine of twenty-five members of
the Harvard University football squad immedi-
ately after the final and most exciting contest
of the season of 1913, and found sugar in
twelve cases. Five of these positive cases
were among substitutes not called upon to enter
the game. The only excited spectator of the Har-

* Since the foregoing sentences were written Hirsch and
Eeinbach have reported (Zeitschrift fiir physiologische
Chemie, 1914, xci, p. 292) a "psychic hyperglycemia" in dogs,
that resulted from fastening the animals to a table. The
blood sugar rose in one instance from 0.11 to 0.14 per cent,
and in another from 0.09 to 0.16 per cent.

76 BODILY CHANGES

vard victory whose urine was examined also had
a marked glycosuria, which on the following day
had disappeared.

Other tests made on students before and after
important scholastic examinations have been pub-
lished by Folin, Denis and Smillie.i" Qf thirty-
four second-year medical students tested, one had
sugar before the examination as well as after-
wards. Of the remaining thirty-three, six, or 18
per cent, had small but unmistakable , traces of
sugar in the urine passed directly following the
ordeal. A similar study was made on second-year
students at a women's college. Of thirty/-six stu-
dents who had no sugar in the urine on the day
before, six, or 17 per cent, eliminated sugar with
the urine passed immediately after the examina-
tion.

From the foregoing results it is reasonable to
conclude that just as in the cat, dog, and rabbit,
so also in man, emotional excitement produces tem-
porary increase of blood sugar.

, The Eole op the Adrenal Glands in Emotional

Glycosuria ,

Since artificial stimulation of the splanchnic
nerves produces glycosuria,^** and since major
emotions, such as rage and fright, are attended by
nervous discharges along splanchnic pathways,
glycosuria as an accompaniment of emotional ex-

INCREASE OF BLOOD SUGAR 77

citement would naturally be expected to occur.
To what extent the adrenal glands which, as
already mentioned, are stimulated to increased
secretion by excitement, might play a part in this
process, has been in dispute. Removal of these
glands or cutting of the nerve fibres supplying
them, according to some observers,^^ prevents
glycosuria after puncture of the fourth ventricle
of the brain (the "sugar puncture," which typically
induces glycosuria) and also after stimulation of
the splanchnics.22 On the other hand, Wert-
heimer and Battez ^* have stated that removal
of the glands does not abolish the effects of sugar
puncture in the cat. It was questionable, there-
fore, whether removal of the adrenal glands would
affect emotional glycosuria.

Evidence on this point I secured with Shohl and
Wright in observations on three animals in which
the adrenals were removed aseptically under ether.
The animals selected had all become quickly ex- '
cited on being bound to the holder, and had mani-
fested glycosuria after about an hour of confine-
ment. In the operation, to avoid' discharge of
adrenin by handling, the adrenal veins were first
tied, and then the glands freed from their attach-
ments and removed as quickly and with as little
manipulation as possible. In one cat the entire
operation was finished in twenty minutes. In two
of the cats a small catheter was introduced into the

78 BODILY CHANGES

urethra througli an incision, so that the bladder
could be emptied at any time.

In all three cases urine that was free from
sugar was obtained soon after the operation. Al-
though the animals deprived of their adrenals
manifested a general lessening of muscular tone,
they still displayed much of their former rage or
excitement when bound. Indeed, one was more ex-
cited after removal of the adrenals than before.
That the animals might not be excessively cooled
they were kept warm with coverings or an elec-
tric heating pad. Although they were now bound
for periods from two to three times as long as
the periods required formerly to cause glycosuria,
no trace of sugar was found in the urine in any
instance. The evidence thus secured tends, there-
fore, to support the view that the adrenal glands
perform an important contributory role in the
glycosuria resulting from splanchnic stimula-
tion.

Possibly the emotional element is in part ac-
countable for the glycosuria observed after pain-
ful stimulation, but conditions causing pain alone
will reasonably explain it. As we have already
seen, strong stimulation of sensory fibres causes
the discharge of impulses along the splanchnic
nerves, and incidentally calls forth an increased
secretion of the adrenal glands. In glycosuria re- -
suiting from painful stimulation, as well as in emo-

INCEEASE OF BLOOD SUGAR 79

tional glycosuria, the adrenal glands may be es-
sential factors.

Later the evidence will be given that sugar is
the optimum source of muscular energy. In pass-
ing, we may note that the liberation of sugar at
a time when great muscular exertion is likely to
be demanded of the organism may be interpreted
as a highly interesting instance of biological
adaptation.

EEFEEENOES

^ Kleen : On Diabetes Mellitus and Glycosuria, Philadel-
ptia, 1900, pp. 22, 37-39.

='Naunyn: Der Diabetes Mellitus, Vienna, 1898, p. 72.

^ Schultze : Verhandlungen der Gesellschaft deutscher
Naturforscher und Aerzte, Cologne, 1908, ii, p. 358.

* Eaimann : Zeitscbrif t f iir Heilkunde, 1902, xxiii, Ab-
theilung iii, pp. 14, 19.

= Mita : Monatshefte fiir Psychiatrie und Neurologie, 1912,
xxxii, p. 159.

^Eolin, Denis and Smillie: Journal of Biological Chem-
istry, 1914, xvii, p. 519.

' Arndt : Zeitschrif t fiir Nervenheilkunde, 1897, x. p. 436.

^Naunyn: Loc. ciL, p. 73; Hirschfeld: Die Zuckerkrank-
heit, Leipzig, 1902, p. 45.

9 Waterman and Smit: Archiv fiir die gesammte Physi-
ologie, 1908, cxxiv, p. 205.

" Henderson and Underbill : American Journal of Physi-
ology, 1911, xxviii, p. 276.

11 Bohm and Hoffmann : Archiv fiir experimentelle Pa-
thologie und Pharmakologie, 1878, viii, p. 295.

"Eckhard: Zeitschrif t fiir Biologic, 1903, xliv, p. 408.

13 Loewy and Rosenberg : Biochemische Zeitschrift, 1913,

Ivi, p. 114.

1* See Abderhalden : Handbuch der biochemischen Ar-
beitsmethoden, Berlin, 1910, ii, p. 181.

80 BODILY CHANGES

1^ Scott : American Journal of Physiology, 1914, xxxiv,
p. 283.

1" Cited by Scott : Loc. cit., p. 296.

1' Roily and Oppermann : Biochemische Zeitschrift, 1913,
xlix, p. 201. Jacobsen: Ihid., 1913, li, p. 449. Hirsch and
Eeinbach: Zeitschrift fiir physiologiscbe Chemie, 1913,
Ixxxvii, p. 122.

Incited by Kleen: Loc. cit., p. 3Y.

1^ Folin, Denis and Smillie : Loc. cit., p. 520.

-" See Macleod : American Journal of Physiology, 1907,
xix, p. 405, also for other references to literature.

^^ See Meyer : Comptes rendus de la Societe de Biologie,
1906, Iviii, p. 1123; Nishi: Archiv fiir experimentelle Pa-
thologic und Pharmakologie, 1909, Ixi, p. 416.

^^ Gautrelet and Thomas : Comptes rendus de la So-
ciete de Biologie, 1909, Ixvii, p. 233 ; and Macleod : Pro-
ceedings of the Society for Experimental Biology and Medi-
cine, 1911, viii, p. 110 (true for left adrenal and left splanch-
nic).

^^ Wertheimer and Battez : Archives Internationales de
Physiologic, 1910, ix, p. 392.

CHAPTER VI

IMPEOVED CONTEACTION OF FATIGUED

MUSCLE AFTEE SPLANCHNIC STIMULATION OF

THE ADEENAL GLAND

In the older literature on the adrenal glands the
deleterious effect of their absence, or the beneficial
effect of injected extracts, on the contraction of
skeletal muscle was not infrequently noted. As
evidence accumulated, however, tending to prove
an important relation between the extract of the
adrenal medulla (adrenin) and the sympathetic
nervous system, the relations with the efficiency of
skeletal muscle began to receive less consideration.

The muscular weakness of persons suffering
from diseased adrenals (Addison's disease) was
well recognized before experimental work on the
glands was begun. Experiments on rabbits were
reported in 1892 by Albanese,^ who showed that
muscles which were stimulated after removal
of the glands were much more exhausted than
when stimulated the same length of time in the
same animal before the removal. Similarly Boi-

81

82 BODILY CHANGES

net 2 reported, in 1895, that rats recently deprived
of their adrenals were much, more quickly ex-
hausted in a revolving cage than were normal
animals.

More direct evidence of the favorable influence
of adrenal extract on skeletal muscle was brought
forward by Oliver and Schafer.^ After inject-
ing the extract subcutaneously into a frog they
found that the excised gastrocnemius muscle regis-
tered a curve of contraction about 33 per cent
higher and about 66 per cent longer than the
corresponding muscle not exposed to the action
of the extract. Similar prolongation of the muscle
curve was observed after injecting the extract
intravenously into a dog. A beneficial effect
of adrenal extract on fatigued muscle, even when
applied to the solution in which the isolated
muscle was contracting, was claimed by Dessy
and Urandis,* who studied the phenomenon in a
salamander.* Further evidence leading to the
same conclusion was offered in a discriminat-

* These earlier investigations, in which an extract of
the entire gland was used, made no distinction between the
action of the medulla and that of the cortex. It may be that
the weakness following removal or disease of the adrenals is
due to absence of the cortex (see Hoskins and Wheelon: Am-
erican Journal of Physiology, 1914, xxxiv, p. 184). Such a
possible effect, however, should not be confused with the
demonstrable influence of injected adrenin (derived from the
adrenal medulla alone) and the similar effects from adrenal
secretion caused by splanchnic stimulation.

CONTRACTION OF FATIGUED MUSCLE 83

ing paper I)y Panella.^ He found that in cold-
blooded animals the active principle of the adre-
nal medulla notably reinforced skeletal muscle,
prolonging its ability to do work, and improv-
ing its contraction when fatigued. In warm-
blooded animals the same effects were observed,
but only after certain experimental procedures,
such as anesthesia and section of the bulb, had
changed them to a condition resembling the cold-
blooded.

The foregoing evidence indicates that removal
of the adrenals has a debilitating effect on muscu-
lar power, and that injection of extracts of the
glands has an invigorating effect. It seemed pos-
sible, therefore, that increased secretion of the
adrenal glands, whether from direct stimulation
of the splanchnic nerves or as a reflex result of
pain or the major emotions, might act as a dyna-
mogenic factor in the performance of muscular
work. With this possibility in mind L. B. Nice
and I ^ first concerned ourselves in a research
which we conducted in 1912.

The general plan of the investigation consisted
primarily in observing the effect of stimulating
the splanchnic nerves, isolated from the spinal
cord, on the contraction of a muscle whose nerve,
also isolated from the spinal cord, was rhyth-
mically and uniformly excited with break induc-
tion shocks. When a muscle is thus stimulated it

84 BODILY CHANGES

at first responds by strong contractions, but as
time passes the contractions become weaker, the
degree of shortening of the muscle becomes less,
and in this state of lessened efficiency it may con-
tinue for a long period to do work. The tired
muscle which is showing continuously and evenly
its inability to respond as it did at first, is said to
have reached the "fatigue level." This level serves
as an excellent basis for testing influences that
may have a beneficial effect on muscular perform-
ance, for the benefit is at once manifested in
greater contraction.

In the experimental arrangement which we used,
only a connection through the circulating blood
existed between the splanchnic region and the
muscle — all nervous relations were severed. Any
change in muscular ability, therefore, occurring
when the splanchnic nerve is stimulated, must
be due to an alteration in the quantity or qual-
ity of the blood supplied to the laboring
muscle.

Cats were used for most experiments, but re-
sults obtained with cats were confirmed on rab-
bits and dogs. To produce anesthesia in the
cats and rabbits, and at the same time to avoid
the fluctuating effects of ether, urethane (2 grams
per kilo body-weight) was given by a stomach tube.
The animals were fastened back downward, over
an electric warming pad, to an animal holder.

CONTEACTION OF FATIGUED MUSCLE 85

Care was taken to maintain the body temperature
at its normal level throughout each experiment.

The Nerve-muscle Preparation

The muscle selected to be fatigued was usually
the extensor of the right hind foot (the tibialis
anticus), though at times the common extensor
muscle of the digits of the same foot was em-
ployed. The anterior tibial nerve which supplies
these muscles was bared for about two centimeters,
severed toward the body, and set in shielded elec-
trodes, around which the skin was fastened by
spring clips. Thus the nerve could be protected,
kept moist, and stimulated without stimulation of
neighboring structures. By a small slit in the skin
the tendon of the muscle was uncovered, and after
a strong thread was tied tightly about it, it was
separated from its insertion. A nerve-muscle
preparation was thereby made which was still con-
nected with its proper blood supply. The prepa-
ration was fixed firmly to the animal holder by
thongs looped around the hock and the foot, i. e.,
on either side of the slit through which the tendon
emerged.

The thread tied to the tendon was passed over
a pulley and down to a pivoted steel bar which
bore a writing point. Both the pulley and this
steel writing lever were supported in a rigid tri-
pod. In the earliest experiments the contracting

86 BODILY CHANGES

muscle was made to lift weights (125 to 175
grams) ; in all the later observations, however,
the muscle pulled against a spring attached below
the steel bar. The tension of the spring as the
muscle began to lift the lever away from the sup-
port was, in most of the experiments, 110 grams,
with an increase of 10 grams as the writing point
was raised 4.5 millimeters. The magnification of
the lever was 3.8.

The stimuli delivered to the anterior tibial nerve
were, in most experiments, single break shocks of
a value barely maximal when applied to the fresh
preparation. The rate of stimulation varied be-
tween 60 and 300 per minute, but was uniform
in any single observation. A rate which was found
generally serviceable was 180 per minute.

Since the anterior tibial nerve contains fibres
affecting blood-vessels, as well as fibres causing
contraction of skeletal muscle, the possibility had
to be considered that stimuli applied to it might
disturb the blood supply of the region. Constric-
tion of the blood vessels would be likely to pro-
duce the most serious disturbance, by lessening
the blood flow to the muscle. The observations
of Bowditch and Warren,'^ that vasodilator rather
than vasoconstrictor effects are produced by
single induction shocks repeated at intervals of
not more than five per second, reassured us as to
the danger of diminishing the blood supply, for

CONTRACTION OF FATIGUED MUSCLE 87

the rate of stimulation in onr experiments never
exceeded five per second and was usually two or
three. Furthermore, in using these different rates
we have never noted any result which could rea-
sonably be attributed to a diminished circulation.

The Splanchnic Preparation
The splanchnic nerves were stimulated in vari-
ous ways. At first only the left splanchnics in
the abdomen were prepared. The nerves, sepa-
rated from the spinal cord, were placed upon
shielded electrodes. The form of electrodes which
was found most satisfactory was that illustrated

FiGTjKB 10. — The shielded electrodes used in stimulating the
splanchnic nerves. For description see text.

in Fig. 10. The instrument was made of a round
rod of hard wood, bevelled to a point at one end,
and grooved on the two sides. Into the grooves
were pressed insulated wires ending in platinum
hooks, which projected beyond the bevelled sur-
face. Around the rod was placed an insulating
rubber tube which was cut out so as to leave the
hooks uncovered when the tube was slipped down-
ward.

In applying the electrodes the left splanchnic
nerves were first freed from their surroundings
and tightly ligatured as close as possible to their

88 BODILY CHANGES

origin. By means of strong compression the con-
ductivity of the nerves was destroyed central
to the ligature. The electrodes were now fixed
in place by thrusting the sharp end of the wooden
rod into the muscles of the back. This was so
done as to bring the platinum hooks a few milli-
meters above the nerves. "With a small seeker
the nerves were next gently lifted over the hooks,
and then the rubber tube was slipped downward
until it came in contact with the body wall. Ab-
sorbent cotton was packed about the lower end
of the electrodes, to take up any fluid that might
appear ; and finally the belly wall was closed with
spring clips. The rubber tube served to keep the
platinum hooks from contact with the muscles of
the back and the movable viscera, while still per-
mitting access to the nerves which were to be
stimulated. This stimulating apparatus could be
quickly applied, and, once in place, needed no
further attention. In some of the experiments
both splanchnic nerves were stimulated in
the thorax. The rubber-covered electrode proved
quite as serviceable there as in the abdo-
men.

The current delivered to the splanchnic nerves
was a rapidly interrupted induced current of such
strength that no effects of spreading were notice-
able. That splanchnic stimulation causes secre-
tion of the adrenal glands has been proved in

CONTEACTION OF FATIGUED MUSCLE 89

many different ways whicH have already been de-
scribed (see p. 41).

The Effects of Splanchnic Stimulation on the
Contraction of Fatigued Muscle

When skeletal muscle is repeatedly stimulated
by a long series of rapidly recurring electric
shocks, its strong contractions gradually grow
weaker until a fairly constant condition is reached.
The record then has an even top — the muscle has
reached the "fatigue level." The effect of splanch-
nic stimulation was tried when the muscle had
been fatigued to this stage. The effect which was
often obtained by stimulating the left splanchnic
nerves is shown in Fig. 11. In this instance the
muscle while relaxed supported no weight, and

FiGtTBB 11. — ^Upper record, contraction of the tibialis
anticus, 80 times a minute, lifting a weight of 125 grams.
Lower record, stimulation of the left splanchnic nerves,
two minutes. Time, half minutes.

while contracting lifted a weight of 125 grams.
The rate of stimulation was 80 per minute.

90

BODILY CHANGES

The muscle record shows a brief initial rise
from the fatigue level, followed by a drop, and
that in turn by another, prolonged rise. The maxi-
mum height of the record is 13.5 millimeters, an
increase of 6 millimeters over the height recorded
before splanchnic stimulation. Thus the muscle
was performing for a short period 80 per cent
more work than before splanchnic stimulation, and
for a considerably longer period exhibited an in-
termediate betterment of its efficiency.

The First Eise in the Muscle Eecord

The brief first elevation in the muscle record
when registered simultaneously with arterial blood
pressure is observed to occur at the same time

Figure 12. — Top record, arterial blood
pressure with membrane manometer. Mid-
dle record, contractions of tibialis anticus
loaded with 125 grams and stimulated 80
times a minute. Bottom record, splanchnic
stimulation (two minutes). Time, half min-
utes.

CONTEACTION OF FATIGUED MUSCLE 91

with the sharp initial rise in the blood-pressure
curve (see Fig. 12). The first sharp rise in blood
pressure is due to contraction of the vessels in
the area of distribution of the splanchnic nerves,
for it does not appear if the alimentary canal is
removed, or if the celiac axis and the superior
and inferior mesenteric arteries are ligated. The
betterment of the muscular contraction is prob-
ably due directly to the better blood supply result-
ing from the increased pressure, for if the adrenal
veins are clipped and the splanchnic nerves are
stimulated, the blood pressure rises as before and
at the same time there may be registered a higher
contraction of the muscle.

The Prolonged Eise in the Muscle Eecord

As Fig. 12 shows, the initial quick uplift in the
blood-pressure record is quickly checked by a drop.
This rapid drop does not appear when the adrenal
veins are obstructed. A similar difference in
blood-pressure records has been noted before and
after excision of the adrenal glands. As Elli-
ott,^ and as Lyman and I " have shown, this
sharp drop after the first rise, and also the subse-
quent elevation of blood pressure, are the conse-
quences of liberation of adrenal secretion into the
circulation. Fig. 12 demonstrates that the pro-
longed rise of the muscle record begins soon after
this characteristic drop in blood pressure.

92 BODILY CHANGES

If after clips have been placed on the adre-
nal veins so that no blood passes from them, the
splanchnic nerves are stimulated, and later the
clips are removed, a slight bnt distinct improve-
ment in the muscular contraction occurs. As in
the experiments of Young and Lehmann,^" in
which the adrenal veins were tied for a time and
then released, the release of the blood which had
been pent in these veins was quickly followed by
a rise of blood pressure. The volume of blood
thus restored to circulation was too slight to ac-
count for the rise of pressure. In conjunction
with the evidence that splanchnic stimulation calls
forth adrenal secretion, the rise may reasonably be
attributed to that secretion. The fact should be
noted, however, that in this instance the prolonged
improvement in muscular contraction did not ap-
pear until the adrenal secretion had been admitted
to the general circulation.

Many variations in the improvement of activity
in fatigued muscle after splanchnic stimulation
were noted in the course of our investigation. The
improvement varied in degree, as indicated by in-
creased height of the record. In some instances
the height of contraction was doubled — a better-
ment by 100 per cent ; in other instances the con-
traction after splanchnic stimulation was only a
small fraction higher than that preceding the stim-
ulation; and in still other instances there was no

CONTRACTION OP FATIGUED MUSCLE 93

betterment whatever. Never, in our experience,
were the augmented contractions equal to the
original strong contractions of the fresh muscle.
The improvement also varied ia degree as in-
dicated by persistence of effect. In some in-
stances the muscle returned to its former working
level within four or five minutes after splanchnic
stimulation ceased (see Fig. 11) ; and in other cases
the muscle continued working with greater effi-
ciency for fifteen or twenty minutes after the stim-
ulation.

The Two Factors: Arterial Pressure and Adrenal
Secretion

The evidence just presented has shown that
splanchnic stimulation improves the contraction of
fatigued muscle. Splanchnic stimulation, however,
has two effects — it increases general arterial pres-
sure and it also causes a discharge of adrenin from
the adrenal glands. The questions now arise —
Does splanchnic stimulation produce the improve-
ment in muscular contraction by increasing the
arterial blood pressure and thereby flushing the
laboring muscles with fresh blood? Or does the
adrenin liberated by splanchnic stimulation act
itself, specifically, to improve the muscular con-
traction? Or may the two factors cooperate?
These questions will be dealt with in the next two
chapters.

94 BODILY CHANGES

EEFEEENCES

^ Albanese : Archives Italiennes de Biologie, 1892, xvii,
p. 243.

2 Boinet : Comptes rendus, Societe de Biologie, 1895, xlvii,
pp. 273, 498.

^ Oliver and Schiif er : Journal of Physiology, 1895, xviii,
p. 263. See also Eadwanska, Anzeiger der Akademie, Krakau,
1910, pp. '728-'736. Eeviewed in Zentralblatt fiir Biochemie
und Biophysik, 1911, xi, p. 467.

*.Dessy and Grandis: Archives Italiennes de Biologie,
1904, xli, p. 231.

^ Panella : Archives Italiennes de Biologie, 1907, xlviii, p.
462.

•^ Cannon and Nice : American Journal of Physiology,
1913, xxxii, p. 44.

' Bowditch and Warren : Journal of Physiology, 1886, vii,
p. 438.

^ Elliott: Journal of Physiology, 1912, xliv, p. 403.

^ Cannon and Lyman : American Journal of Physiology,
1913, xxxi, p. 376.

^° Young and Lehmann : Journal of Physiology, 1908,
xxxvii, p. liv.

CHAPTER VII

THE EFFECTS ON CONTEAOTION OF FATIGUED

MUSCLE OF VARYING THE ARTERIAL

BLOOD PRESSURE

That great excitement is accompanied by sym-
pathetic innervations which increase the contrac-
tion of the small arteries, render unusually forc-
ible the heart beat, and consequently raise arterial
pressure, has already been pointed out (see p. 26).
Indeed, the counsel to avoid circumstances likely
to lead to such excitement, which is given to per-
sons with hardened arteries or with weak hearts,
is based on the liability of serious consequences,
either in the heart or in the vessels, that might
arise from an emotional increase of pressure in
these pathological conditions. That great muscu-
lar effort also is accompanied by heightened arte-
rial pressure is equally well known, and is avoided
by persons likely to be injured by it. Both in ex-
citement and in strong exertion the blood is forced
in large degree from the capacious vessels of the
abdomen into other parts of the body. In excite-

95

96 BODILY CHANGES

ment the abdominal arteries and veins are con-
tracted by impulses from the splanchnic nerves.
In violent effort the diaphragm and the muscles
of the belly wall are voluntarily and antagonistic-
ally contracted in order to stiffen the trunk as a
support for the arms ; and the increased abdominal
pressure which results forces blood out of that
region and does not permit reaccumulation. The
general arterial pressure in man, as McCurdy ^
has shown, may suddenly rise during extreme
physical effort, from approximately 110 millime-
ters to 180 millimeters of mercury.

The Effect of Increasing Arterial Pressure

What effect the increase of arterial pressure, re-
sulting from excitement or physical strain, may
have on muscular efficiency, has received only
slight consideration. Nice and I found there was
need of careful study of the relations between
arterial pressure and muscular ability, and, in
1913, one of my students, 0. M. Gruber, under-
took to make clearer these relations.

The methods of anesthesia and stimulation used
by Gruber were similar to those described in
the last chapter. The arterial blood pressure was
registered from the right carotid or the femoral
artery by means of a mercury manometer. A
time marker indicating half -minute intervals was
placed at the atmospheric pressure level of the

FATIGUE AND BLOOD PRESSURE 97

manometer. And since the blood-pressure style,
the writing point of the muscle lever, and the time
signal were all set in a vertical line on the surface
of the recording drum, at any given muscular con-
traction the height of blood pressure was simul-
taneously registered.

To increase general arterial pressure two meth-
ods were used: the spinal cord was stimulated in
the cervical region through platinum electrodes, or
the left splanchnic nerves were stimulated after
the left adrenal gland had been excluded from the
circulation. This was done in order to avoid any
influence which adrenal secretion might exert. It
is assumed in these experiments that vessels sup-
plying active muscles would be actively dilated, as
Kaufmann ^ has shown, and would, therefore, in
case of a general increase of blood pressure, de-
liver a larger volume of blood to the area they
supply. The effects of increased arterial pressure
are illustrated in Figs. 13, 14 and 15. In the ex-
periment represented in Fig. 13, the rise of blood
pressure was produced by stimulation of the cer-
vical cord, and in Figs. 14 and 15 by stimulation
of the left splanchnic nerves after the left adre-
nal gland had been tied off.

The original blood pressure in Fig. 13 was 120
millimeters of mercury. This was increased by
62 millimeters, with a rise of only 8.4 per cent in
the height of contraction of the fatigued muscle.

98

BODILY CHANGES

Figure 13. — In this and the following
records, the upper curve indicates the
blood pressure, the middle Mne muscu-
lar contraction, and the lower line the time
in 30 seconds (also zero blood pressure.)
Between the arrows the exposed cervical
spinal cord was stimulated.

In Fig. 14 the original blood pressure was 100
millimeters of mercury. By increasing this pres-

FATIGUE AND BLOOD PRESSURE 99

sure 32 millimeters there resulted simultaneous
betterment of 9.8 per cent in the height of muscu-
lar contraction. In Fig. 14 B the arterial pres-
sure was raised 26 millimeters and the height of

V-'

''^tUiWutflUkttflWiM^

^2

T i

t 4.

A B C

FiGTJRB 14. — Stimulation of the left splanchnic nerves (left
adrenal gland tied off) during the periods indicated by the arrows.

contraction increased correspondingly 7 per cent.
In Fig. 14 C no appreciable betterment can be seen
although the blood pressure rose 18 millimeters.
In Fig. 15 the original blood pressure was low
— 68 millimeters of mercury. This was increased
in Fig. 15 A by 18 millimeters (the same as in

100 BODILY CHANGES

Fig. 14 C without effect), and there resulted an in-
crease of 20 per cent in the height of contraction.
In Fig. 15 B the pressure was raised 24 millime-

■\,,..

- ,-, . 1 p : , 1 ,-, 1 — 1 1 r

A B C

Figure 15. — During the periods indicated in the
time line the left splanchnic nerves were stimulated.
The vessels of the left adrenal gland were tied off.

ters with a corresponding increase of 90 per cent
in the muscular contraction ; and in Fig. 15 C 30
millimeters with a betterment of 125 per cent.

Comparison of Figs. 13, 14 and 15 reveals that
the improvement of contraction of fatigued mus-
cle is much greater when the blood pressure is
raised, even slightly, from a low level, than when
it is raised, perhaps to a very marked degree,
from a high level. In one of the experiments per-
formed by Nice and myself the arterial pressure

FATIGUE AND BLOOD PRESSURE 101

was increased by splanchnic stimulation from the
low level of 48 millimeters of mercury to 110 milli-
meters, and the height of the muscular contrac-
tions was increased about sixfold (see Fig. 16).

Figure 16. — The bottom record (zero of blood pressure) shows
stimulation of left splanchnics; between the arrows the pressure was
kept from rising by compression of heart.

Results confirming those described above were
obtained by Gruber in a study of the effects of
splanchnic stimulation on the irritability of mus-
cle when fatigued. In a series of eleven observa-
tions the average value of the barely effective
stimulus (the "threshold" stimulus) had to be in-
creased as the condition of fatigue developed. It

102 BODILY CHANGES

was increased for the nerve-muscle by 25 per cent
and for the muscle by 75 per cent. The left
splanchnic nerves, disconnected from the left adre-
nal gland, were now stimulated. The arterial pres-
sure, which had varied between 90 and 100 milli-
meters of mercury, was raised at least 40 milli-
meters. As a result of splanchnic stimulation
there was an average recovery of 42 per cent in
the nerve-muscle and of 46 per cent in the muscle.
The increased general blood pressure was effec-
tive, therefore, quite apart from any possible
action of adrenal secretion, in largely restoring to
the fatigued structures their normal irritability.

The Effect of Decreasing Arterial Pressure

Inasmuch as an increase in arterial pressure
produces an increase in the height of contraction
of fatigued muscle, it is readily supposable that
a decrease in the pressure would have the oppo-
site effect. Such is the case only when the blood
pressure falls below the region of 90 to 100 milli-
meters of mercury. Thus if the arterial pressure
stands at 150 millimeters of mercury, it has to
fall approximately 55 to 65 millimeters before
causing a decrease in the height of contraction.
Fig. 17 is the record of an experiment in which
the blood pressure was lowered by lessening the
output of blood from the heart by compressing the
thorax. The record shows that when the pressure

FATIGUE AND BLOOD PRESSURE 103

was lowered from 120 to 100 millimeters of mer-
cury (A), there was no appreciable decrease in
the height of contraction; when lowered to 90

Figure 17. — The arrows indicate the points at which the thorax
began to be compressed in order to lessen the output of blood
from the heart.

millimeters (B), there resulted a decrease of 2.4
per cent; when to 80 millimeters of mercury (C),
a decrease of 7 per cent; and when to 70 milli-
meters (D), a decrease of 17.3 per cent. Results
similar to those represented in Fig. 17 were ob-
tained by pulling on a string looped about the

104 BODILY CHANGES

aorta just above its iliac branches, thus lessening
the flow to the hind limbs.

The region of 90 to 100 millimeters of mercury
may therefore be regarded as the critical region
at which a falling blood pressure begins to be ac-
companied by a concurrent lessening of the effi-
ciency of muscular contraction, when the muscle
is kept in continued activity. It is at that region
that the blood flow is dangerously near to being
inadequate.

An Explanationotjth^ Effects op Varying the Arterul
""■ Pressure

How are these effects of ^ucreasing and decreas-
ing the arterial blood pressure most reasonably
explained? There is abundant evidence that fa-
tigue products accumulate in a muscle which is
doing work, and also that these metabolites inter-
fere with efficient contraction. As Eanke ^ long
ago demonstrated, if a muscle, deprived of circu-
lating blood, is fatigued to a standstill, and then
the circulation is restored, the muscle again re-
sponds for a short time to stimulation, because
the waste has been neutralized or swept away by
the fresh blood. When the blood pressure is at
its normal height for warm-blooded animals
(about 120 millimeters of mercury, see Fig. 13),
the flow appears to be adequate to wash out the
depressive metabolites, at least in the single muscle

FATIGUE AND BLOOD PRESSURE 105
used in these experiments, because a large rise of

pressuTe_praduQ©s-%at4ittte-S
level. On the other hand, when the pressure is
abnormally low, the flow is inadequate, and the
waste products are permitted to accumulate^ahd
clog the action of the muscle. Under such circum-
stances a rise of pressure has a. very striking bene-
ficial effect.

It is noteworthy that the best results of adre-
nin on fatigued muscle reported by previous ob-
servers were obtained from studies on cold-blooded
animals. In these animals the circulation is main-
tained normally by an arterial pressure about one-
third that of warm-blooded animals. Injection of
adrenin in an amount which would not shut off the
blood supply would, by greatly raising the arterial
pressure, markedly increase the circulation of
blood in the active muscle. In short, the conditions
in cold-blooded animals are quite like those in the
pithed mammal with an arterial pressure of about
50 millimeters of mercury (see Fig. 16). Under
these conditions the improved circulation causes
a remarkable recovery from fatigue. That notable
results of adrenin on fatigue are observed in
warm-blooded animals only, when they are deeply
anaesthetized or are ^epriVed of the medulla was
claimed by Panella.* He apparently believed
that in normal mammalian conditions adrenia has
little effect because quickly destroyed, whereas in

106 BODILY CHANGES

the cold-blooded animals, and in mammals whose
respiratory, circulatory, and thermogenic states
are made similar to the cold-blooded by anaesthesia
or pithing, the contrary is true. In accordance
with our observations of the effects of blood pres-
sure on fatigued muscle, we would explain Panel-
la's results not as he has done but as due to two
factors. First, the efficiency of the muscle, when
blood pressure is low, follows the ups and downs
of pressure much more directly than when the
pressure is high. And second, a given dose of
adrenin always raises a low blood pressure in
atonic vessels. The improvement of circulation
is capable of explaining, therefore, the main re-
sults obtained in cold-blooded animals and in
pithed mammals.

Oliver and Schafer reported unusually effective
contractions in muscles removed from the body
after adrenal extract had been injected. As shown
in Fig. 16, however, the fact that the circulation
had teen improved results in continued greater effi-
ciency of the contracting muscle. Oliver and Scha-
fer's observation may reasonably be accounted for
on this basis.

The Value of Increased Arterial Pressure m Pain and
Strong Emotion

As stated in a previous paragraph, there is evi-
dence that the vessels supplying a muscle dilate

FATIGUE AND BLOOD PEESSUEE 107

when the muscle becomes active. And although
the normal blood pressure (about 120 millimeters
of mercury) may be able to keep adequately sup-
plied with blood the single muscle used in our in-
vestigation, a higher pressure might be required
when more muscles are involved in activity, for
a more widely spread dilation might then reduce
the pressure to the point at which there would be
insufficient circulation in active organs. Further-
more, with many muscles active, the amount of
waste would be greatly augmented, and the need
for abundant blood supply would thereby to a
like degree be increased. For both reasons a rise
of general arterial pressure would prove advan-
tageous. The high pressure developed in excite-
ment and pain, therefore, might be specially ser-
viceable in the muscular activities which are likely
to accompany excitement and pain.

Tn connection with the foregoing considerations,
the action of adrenin on the distribution of blood
in the body is highly interesting. By measuring
alterations in the volume of various viscera and
the limbs, Oliver and Schafer ^ proved that the
viscera of the splanchnic area — e. g., the spleen,
the kidneys, and the intestines — suffer a consider-
able decrease of volume when adrenin is adminis-
tered, whereas the limbs into which the blood is
forced from the splanchnic region actually in-
crease in size. The action of adrenin indicates the

108 BODILY CHANGES

relative degrees of sympathetic innervations. In
other words, at times of pain and excitement sym-
pathetic discharges, probably aided by the adrenal
secretion simultaneously liberated, will drive the
blood out of the vegetative organs of the interior,
which serve the routine needs of the body, into
the skeletal muscles which have to meet by extra
action the urgent demands of struggle or escape.
But there are exceptions to the general state-
"n ient t ha i •by 'Sdrenin the viscera are emptied of
their blood, ^t is well known that adrenin has a
vasodilator, not a vasoconstrictor, action on the
arteries of the heart; it is well known also that
adrenin affects the vessels of the brain and the
lungs only slightly if at all. From this evidence
we may infer that sympathetic impulses, though
causing constriction of the arteries of the abdomi-
nal viscera, have no effective influence on those of
the pulmonary and intracranial areas and actually
increase the blood supply to the heart. Thus the
absolutely and immediately essential organs —
those the ancients called the "tripod of life" — the
heart, the lungs, the brain (as well as its instru-
ments, the skeletal muscles) — are in times jjf, ex-
citement abundantly supplied with blood taken
from organs of less importance in criticar"in6-
inents. This shifting of the blood so that there is
an assured adequate supply to structures" eSMntlal
for the preservation of the individual may reason-

FATIGUE AND BLOOD PRESSURE 109

ably be interpreted as a fact of prime biological
significance. It wil lJbej'Msgjd . in .its.,.pr,ape]j- setti-ng- /
when the_otb.eX-,eziclence of bodily changes in pain I
and excitement have. been. presented. ^

EEFEEENCES

^ McOurdy : American Journal of Physiology, 1901, v,
p. 98.

2 Kaufmann : Archives de Physiologie, 1892, xxiv, p. 283.

^Eanke: Archiv fiir Anatomie, 1863, p. 446.

* Panella : Archives Italiennes de Biologie, 190Y, xlviii,
p. 462.

° Oliver and Schafer : Journal of Physiology, 1895, xviii,
p. 240.

/

CHAPTER VIII

THE SPECIFIC EOLE OE ADEENIN IN
COUNTERACTING THE EFFECTS OF FATIGUE

As a muscle approaches its fatigue level, its con-
tractions are decreased in height. Higher contrac-
tions will again be elicited if the stimulus is in-
creased. Although these phenomena are well
known, no adequate analysis of their causes has
been advanced. A number of factors are probably
operative in decreasing the height of contraction :
(1) The using up of available energy-producing
material; (2) the accumulation of metabolites in
the fatigued muscle; (3) polarization of the nerve
at the point of repeated electrical stimulation ; and
(4) a decrease of irritability. It may be that there
are interactions between these factors within the
muscle, e. g., the second may cause the fourth.

Variations of the Threshold Stimulus as a Measure of
Irritability

The last of the factors mentioned above — the
effect of fatigue on the irritability of the nerve-
muscle combination, or on the muscle alone — can

110

FATIGUE AND ADRENIN 111

be tested by determining variations in the least
stimulus capable of causing the slightest contrac-
tion, the so-called "threshold stimulus." As the
irritability lessens, the threshold ' stimulus must
necessarily be higher. The height of the threshold
is therefore a measure of irritability. How does
fatigue affect the irritability of nerve-muscle and
muscle ? How is the irritability of fatigued struc-
tures affected by rest? How is it influenced by
adrenin or by adrenal secretion? Answers to
these questions were sought in researches carried
on by C. M. Gruber ^ in 1913.

The Method of Determining the Threshold Stimulus

The neuro-muscular arrangements used in these
researches were in many respects similar to those
already described in the account of experiments
by Nice and myself. To avoid the influence of an
anesthetic some of the animals were decerebrated
under ether and then used as in the experiments in
which urethane was the anesthetic. The nerve
(the peroneus communis) supplying the tibialis an-
ticus muscle was bared and severed ; and near the
cut end shielded platinum electrodes were applied.
These electrodes were used in fatiguing the muscle.
Between these electrodes and the muscle other
platinum electrodes could be quickly applied to de-
termine the threshold stimulus and the tissue re-
sistance. These second electrodes were removed

112 BODILY CHANGES

except wlien in use, and when replaced were set
always in the same position. Care was taken, be-
fore replacing them, to wipe off moisture on the
nerve or on the platinum points.

For determining the threshold stimulus of the
muscle the skin and other overlying tissues were
cut away from the tibialis anticus in two places
about 5 centimeters apart. Through these open-
ings platinum needle electrodes could be thrust
into the muscle whenever readings were to be
taken. Local polarization was avoided by rein-
serting the needles into fresh points on the exposed
areas whenever new readings were to be taken.

The tendon of the tibialis anticus was attached,
as in the previous experiments, by a strong thread
passing about pulleys to a lever which when lifted
stretched a spring. During the determination of
the threshold the spring was detached from the
lever, so that only the pull of the lever itself
(about 15 grams) was exerted on the muscle.

The method of measuring the stimulating value
of the electric current which was used in testing
the threshold was that devised by E. Gr. Martin* of
the Harvard Laboratory — a method by which the
strength of an induced electric shock is calculable
in definite units. If the tissue resistance enters

* For a full account of Dr. Martin's method of calculating'
the strength of electric stimuli, see Martin : The Measurement
of Induction Shocks, New York, 1912.

FATIGUE AND ADEENIN 113

into the calculation these are called ^ units. When
the threshold of the nerve-muscle was taken, the
apparatus for the determination was connected
with the nerve through the electrodes nearer the
muscle. They were separated from the fatiguing
electrodes by more than 3 centimeters, and ar-
ranged so that the kathode was next the muscle.
When the threshold of the muscle was taken direct-
ly the apparatus was connected with the muscle
through platinum needle electrodes thrust into it.
The position of the secondary coil of the inducto-
rium, in every case, was read by moving it away
from the primary coil until the very smallest pos-
sible contraction of the muscle was obtained. Four
of these readings were made, one with tissue resist-
ance, the others with 10,000, 20,000, and 30,000
ohms additional resistance in the secondary cir-
cuit. Only break shocks were employed — the
make shocks were short-circuited. Immediately
after the determination of the position of the sec-
ondary coil, and before the electrodes were re-
moved or disconnected, three readings of the tis-
sue resistance were made. From these data four
values for /3 were calculated.

The strength of the primary current for deter-
mining the threshold of the nerve-muscle was usu-
ally .01 ampere, but in a few cases .05 ampere was
used. For normal muscle it was .05 ampere and
for denervated muscle 1.0 ampere. The inducto-

114 BODILY CHANGES

rium, which was used throughout, had a secondary
resistance of 1400 ohms. This was added to the
average tissue resistance in making corrections —
corrections were made also for core magnetiza-
ti on.

The Lessening op Neuro-musculae Irritability by Fatigue
The threshold for the peroneus communis nerve
in decerebrate animals varied from 0.319 to 2.96
units, with an average in sixteen experiments of
1.179.* This average is the same as that found by
E. L. Porter ^ for the radial nerve in the spinal
cat. For animals under urethane anesthesia a
higher average was obtained. In these it varied
from .644 to 7.05, or an average in ten experiments
of 3.081.

The threshold for the tibialis anticus muscle
varied in the decerebrate animals from 6.75 units
to 33.07, or an average in fifteen experiments of
18.8. Ten experiments were performed under ure-
thane anesthesia and the threshold varied from
12.53 to 54.9, with an average of 29.84 j3 units.
From these results it is evident that anesthesia
notably affects the threshold.

E. L. Porter proved, by experiments carried on
in the Harvard Physiological Laboratory, that the
threshold of an undisturbed nerve-muscle remains

* For the detailed data of these and other quantitative ex-
periments, the reader should consult the tables in the original
papers.

FATiaUE AND ADRENIN 115

constant for hours, and his observation was con-
firmed by Gruber (see Fig. 19). If, therefore,
after fatigue, a change exists in the threshold, this
change is necessarily the result of alterations set
up by the fatigue process in the nerve-muscle or
muscle.

After fatigue the threshold of the nerve-muscle,
in sixteen decerebrate animals, increased from an
average of 1.179 to 3.34 — an increase of 183 per
cent. In ten animals under urethane anesthesia
the threshold after fatigue increased from a nor-
mal average of 3.08 to 9.408 — an increase of 208
per cent.

An equal increase in the threshold stimulus was
obtained from the normal muscle directly. In de-
cerebrate animals the normal threshold of 18.8
units was increased by fatigue to 69.54, or an in-
crease of 274 per cent. With urethane anesthesia
the threshold increased from 29.849 to 66.238, or
an increase of 122 per cent.

Fig. 18, plotted from the data of one of the many
experiments, shows the relative heights of the
threshold before and after fatigue. The corre-
spondence of the two readings of the threshold, one
from the nerve supplying the muscle and the other
from the muscle directly, served as a check on the
electrodes. The broken line in the figure repre-
sents the threshold (in units) of the nerve-muscle,
and the continuous line that of the muscle. The

116 BODILY CHANGES

threshold values of the nerve-muscle have been
magnified ten times in order to bring the two rec-
ords close together. In this experiment the thresh-

FiGTJEE 18. — A record plotted from the data of one experiment.
The time intervals in minutes are registered on the abscissa; the
value of the threshold in units is registered on the ordinate. The
continuous line is the record of the muscle, the broken Une that of
the nerve-muscle. The values for the nerve-muscle have been
magnified ten times, those for the muscle are normal.

(1) Normal values of the threshold.

(2) Fatigue thresholds after one hour's work, hfting 120 grams
240 times a minute.

(3 and 4) The threshold after rest.

old of the muscle after fatigue (i.e., at 2) is 167 per
cent higher than the normal threshold (at 1), while
that of the nerve-muscle after fatigue is 30.5 per
cent higher than its normal.

Evidently a direct relation exists between the
duration of work and the increase of threshold.
For instance, the threshold is higher after a muscle
is fatigued for two hours than it is at the end of

FATIGUE AND ADEENIN 117

the first hour. The relation between the work
done and the threshold is not so clear. In some
animals the thresholds were higher after 120 grams
had been lifted 120 times a minute for 30 minutes
than they were in others in which 200 grams had
been lifted 240 times a minute for the same period.
The muscle in the latter instances did almost four
times as much work, yet the threshold was lower.
The difference may be due to the general condi-
tion of the animal.

A few experiments were performed on animals
in which the nerve supplying the muscle was cut
seven to fourteen days previous to the experiment.
The muscle, therefore, had within it no living
nerve fibres. The average normal threshold for
the denervated muscle in 6 animals was 61.28 units.
As in the normal muscle, the percentage increase
due to fatigue was large.

The Slow Eestoration of Fatigued Muscle to Normal
Ireitability by Eest

That rest decreases the fatigue threshold of both
nerve-muscle and muscle can be seen in Fig. 18.
The time taken for total recovery, however, is de-
pendent upon the amount of work done, but this
change, like that of fatigue, varies widely with
different individuals. In some animals the thresh-
old returned to normal in 15 minutes; in others,
in which the same amount of work was done, it was

118 BODILY CHANGES

still above normal even after 2 hours of rest. This
may be due to the condition of the animals — in
some the metabolites are probably eliminated more
rapidly than in others. There were also variations
in the rate of restoration of the normal threshold
when tested on the nerve and when tested on the
muscle in the same animal. In Fig. 18 (at 3) the
nerve-muscle returned to normal in 30 miautes,
whereas the muscle (at 4) after an hour's rest had
not returned to normal by a few /3 units. This,
however, is not typical of all nerve-muscles and
muscles. The opposite condition — that in which
the muscle returned to normal before the nerve-
muscle — occurred in as many cases as did the con-
dition just cited. The failure of the two tissues to
alter uniformly in the same direction may be ex-
plained as due to variations in the location of the
electrodes when thrust into the muscle at different
times (e. g., whether near nerve filaments or not).
The results from observations made on the nerve
are more likely to be uniform and reliable than are
those from the muscle.

The time required for the restoration of the
threshold from fatigue to normal, in denervated
muscles, is approximately the same as that for the
normal muscle.

FATiaUE AND ADEENIN 119

The Quick Eestoration of Fatigued Husole to Normal
Irritability by AoRENDf

The foregoing observations showed that fatigue
raises the normal threshold of a muscle, on the av-
erage, between 100 and 200 per cent (it may be in-
creased more than 600 per cent) ; that this increase
is dependent on the time the muscle works, but
also varies with the animal ; that rest, 15 minutes to
2 hours, restores the normal irritability ; and that ^
this recovery of the threshold depends upon the
time given to rest, the duration of the work, and
also upon the condition of the animal. The prob-
lem which was next attacked by Gruber was that of
learning whether the higher contractions of fa-
tigued muscle after splanchnic stimulation could
be attributed to any influence which adrenal secre-
tion might have in restoring the normal irritability.
To gain insight iato the probabilities he tried first
the effects of injecting slowly into the jugular vein
physiological amounts of adrenin.*

The normal threshold of the peroneus communis
nerve varied in the animals used in this series of
observations from 0.35 to 5.45 units, with an aver-
age in nine experiments of 1.3, a figure close to the
1.179 found in the earlier series on the effect of
fatigue. For the tibialis anticus muscle, in which
the nerve-endings were intact, the threshold varied

* The form of adrenin used in these and in other injections
was fresh adrenalin made by Parke, Davis & Co.

120 BODILY CHANGES

from 6.75 to 49.3 units, with an average in the nine
experiments of 22.2. This is slightly higher than
that cited for this same muscle in the earlier series.
By fatigue the threshold of the nerve-muscle was
increased from an average of 1.3 to an average of
3.3 units, an increase of 154 per cent. The muscle
increased from an average of 22.2 to an average of
59.6, an increase of 169 per cent. After an injec-
tion of 0.1 to 0.5 cubic centimeters of adrenin
(1:100,000) the fatigue threshold was decreased
ivithin five minutes in the nerve-muscle from an
average of 3.3 to 1.8, a recovery of 75 per cent, and
in the muscle from an average of 59.6 to 42.4, a re-
covery of 46 per cent. To prove that this effect of
adrenin is a counteraction of the effects of fatigue,
Gruber determined the threshold for muscle and
nerve-muscle in non-fatigued animals before and
after adrenin injection. He found that in these
cases no lowering of threshold occurred, a result in
marked contrast with the pronounced and prompt
lowering induced by this agent in muscles when
fatigued.

Figs. 19 and 20, plotted from the data of two of
the experiments, show the relative heights of the
threshold before and after an injection of adrenin.
The close correspondence of the two readings of
the threshold, one from the nerve supplying the
muscle, the other from the muscle directly, served
to show that there was no fault in the electrodes.

FATIGUE AND ADEENIN 121

The continuous line in the Figures represents the
threshold (in units) of the muscle, the broken line
that of the nerve-muscle. The threshold of the
nerve-muscle is magnified 100 times in Fig. 19 and
10 times in Fig. 20. In Fig. 19 (at 2 and 4) the
threshold was taken after an intravenous injection
of 0.1 and 0.2 cubic centimeter of adrenin respec-
tively.

These examples show that adrenin does not af-
fect the threshold of the normal non-fatigued mus-
cle when tested either on the muscle directly or on
the nerve-muscle. In Fig. 19 (at 3) the observa-
tion taken after two hours of rest illustrates the
constancy of the threshold under these circum-
stances.

In Fig. 19 the normal threshold was increased by
fatigue (at 5) — the muscle had been pulling 120
times a minute for one hour on a spring hav-
ing an initial tension of 120 grams — from 30.0
to 51.6 units, an increase of 72 per cent; and in
the nerve-muscle from 0.62 to 0.89 units, an
increase of 46 per cent. The threshold (at 6)
was taken five minutes after injecting 0.1 cubic
centimeter of adrenin (1:100,000). The thresh-
old of the muscle was lowered from 51.6 to
38.0 units, a recovery of 62 per cent; that of the
nerve-muscle from 0.89 to 0.79 units, a recovery of
37 per cent. After another injection of 0.5 cubic
centimeter of adrenin the thresholds (at 7) were

122

BODILY CHANGES

taken; that of the nerve-muscle dropped to normal
— 0.59 miits — a recovery of 100 per cent, and that

90
80

I

70

'-

/ 1

z

-»« 1

«0|

^2 *""

34 '7

£0

5

A

40

so'

^^-t--f

L 134/1 1

3:30

Figure 19. — A record plotted from the
data of one experiment. The time inter-
vals in hours and minutes are represented
on the abscissa; the values of the threshold
in ;3 units are represented on the ordinate.
The continuous line is the record of the
muscle, the broken line that of the nerve-
muscle. The nerve-muscle record is mag-
nified 100 times; that of the muscle is nor-
mal.

(1) Normal threshold stimulus. (2)
Threshold five minutes after an intraven-
ous injection of 0.1 cubic centimeter of ad-
renin (1:100,000) without previous fatigue.

(3) Threshold after a rest of two hours.

(4) Threshold five minutes after an injec-
tion of 0.2 cubic centimeter of adrenin
(1:100,000) without previous fatigue. (5)
Threshold after one hour's fatigue. The
muscle contracted 120 times per minute
against a spring having an initial tension
of 120 grams. (6) Threshold five minutes
after an injection (0.1 cubic centimeter) of
adrenin (1:100,000). (7) Threshold five
minutes after another injection of adrenin
(0.5 cubic centimeter of a 1:100,000 solu-
tion).

of the muscle remained unaltered — 26 per cent
above its normal threshold.
In Fig. 20 the threshold (at 5) was taken five

FATIGUE AND ADEENIN 123

mimites after an injection of 0.1 cubic centimeter
of adrenin. The drop here was as large as that
shown in Fig. 19. The threshold taken from the

-

40

~

2

M

^

/ ^^'

to

I

/

h- ^ ^

to I

I

2

,'" 3 4

-^^-^~-~t .^

.

I 1 1 1 1 f 1 1 1

-

1 1 1 1 1 1 M 1

:S0 1 1:30 t tSO 3 3:30 «

4:80

Figure 20. — A record plotted from the data of one experiment.
The time intervals in hours and minutes are registered on the
abscissa; the values of the threshold in units are registered on the
ordinate. The continuous line is the record of the muscle, the
broken line that of the nerve-muscle. The record of the nerve-
muscle is magnified ten times; that of the muscle is normal.

(1) Normal threshold. (2) The threshold after one hour's
fatigue. The muscle contracted 120 times per minute against a
spring having an initial tension of 120 grams. (3 and 4) Thresh-
olds after rest; after 60 minutes (3), and after 90 minutes (4).
(5) Threshold five minutes after an injection of adrenin (0.1
cubic centimeter of a 1:100,000 solution). (6 and 7) Thresholds
after rest; after 60 minutes (6), and after 90 minutes (7).

muscle directly was lowered from 30.6 to 18 units,
a recovery of 61 per cent; the nerve-muscle from
1.08 to 0.87 units, a recovery of 51 per cent. That
this sudden decrease cannot be due«to rest is shown
in the same Figure (at 3 and 4). These readings
were made after 60 and 90 minutes' rest respective-
ly. The sharp decline in the record (at 5) indi-
cates distinctly the remarkable restorative influ-

124 BODILY CHANGES

enee of adrenin in promptly lowering tlie high
fatigue threshold of neuro-muscular irritability.

The Evidence that the Eestorative Action op Adrenin is
Specific

As stated in describing the effects of arterial
blood pressure, an increase of pressure is capable
of causing a decided loweriug of the neuro-muscu-
lar threshold after fatigue. Is it not possible that
adrenin produces its beneficial effects by better-
ing the circulation 1

Nice and I had argued that the higher contrac-
tions of fatigued muscle, that follow stimulation or
injection of adrenin, could not be wholly due to
improved blood flow through the muscle, for when
by traction on the aorta or compression of the
thorax arterial pressure in the hind legs was pre-
vented from rising, splanchnic stimulation still
caused a distinct improvement, the initial appear-
ance of which coincided with the point in the blood-
pressure curve at which evidence of adrenal secre-
tion appeared. And, furthermore, the improve-
ment was seen also when adrenin was given intra-
venously in such weak solution (1:100,000) as to
produce a fall instead of a rise of arterial pressure.
Lyman and I had shown that this fall of pressure
was due to a dilator effect of adrenin. Since the
blood vessels of the fatigued muscle were dilated by
severance of their nerves when the nerve trunk was

FATIGUE AND ADEENIN

125

cut, and, besides, as previously stated (see p. 86),
were being stimulated through, their nerves at a
rate favorable to relaxation, it seemed hardly prob-

%

fi

.""^''"'^

i

\ \-^ \ \ \ \ \ \

FiGtTRB 21. — Top record, blood pressure
with mercury manometer. Middle record,
contractions of the tibialis anticus muscle
240 times per minute against a spring with
an initial tension of 120 grams. Bottom
record (zero blood pressure), injection of
0.4 cubic centimeter of adrenin (1:100,-
000). Time in half minutes.

able that adrenin could produce its beneficial effect
by further dilation of the vessels and by consequent
flushing of the muscle with an extra supply of
blood.^ The lowering of blood pressure had

126 BODILY CHANGES

been proved to have no other effect than to impair
the action of the muscle ( see p. 103 ) . Although the
chances were thus against an interpretation of the
beneficial influence of adrenin through action on
the circulation, it was thought desirable to test
the possibility by comparing its effect with that
of another vasodilator — amyl nitrite.

Figs. 21 and 22 are curves obtained from the left
tibialis anticus muscle. The rate of stimulation
was 240 times a minute.

The muscle in Fig. 21 contracted against a spring
having an initial tension of 120 grams, and that in
Fig. 22 against an initial tension of 100 grams. In
Fig. 21, at the point indicated on the base line, 0.4
cubic centimeter of adrenin (1:100,000) was in-
jected into the left external jugular vein. There
resulted a fall of 25 millimeters of mercury in the
arterial pressure and a concurrent betterment of 15
per cent in the height of contraction, requiring
two minutes and fifteen seconds of fatigue (about
540 contractions) before it returned to the former
level. In Fig. 22, at the point indicated by the
arrow, a solution of amyl nitrite was injected into
the right external jugular vein. There resulted a
fall of 70 millimeters of mercury in arterial pres-
sure and a betterment of 4.1 per cent in the height
of muscular contraction, requiring fifteen seconds
of fatigue (about 60 contractions) to decrease the
height of contraction to its former level. In

FATIGUE AND ADEENIN

127

Figure 22. — Top record,
blood pressure with mercury
manometer. Middle record, con-
tractions of tibialis anlicus mus-
cle 240 per minute against a
spring with an initial tension of
100 grams direct load. Bottom
record (zero blood pressure), time
in half minutes. The arrow indi-
cates the point at which a solu-
tion of amyl nitrite was injected.

128 BODILY CHANGES

neither case did the blood pressure fall below the
critical region (see p. 104).*

Although the fall in arterial pressure caused by
dilation of the vessels due to amyl nitrite was al-
most three times as great as that produced by the
adrenin, yet the resultant betterment was only
about one-fourth the percentage height and lasted
but one-ninth the time. In all cases in which these
solutions caused an equal fall in arterial pressure,
adrenin caused higher contractions, whereas amyl
nitrite caused no appreciable change.

The Point op Action of Adrenin in Muscle

From the evidence presented in the foregoing
pages it is clear that adrenin somehow is able to
bring about a rapid recovery of normal irritability
of muscle after the irritability has been much less-
ened by fatigue, and that the higher contractions
of a fatigued muscle after an injection of adrenin
are due, certainly in part, to some specific action
of this substance and not wholly to its influence~o5~
tlie circulation. Some of the earlier investigators

* In some cases after injection of amyl nitrite the normal
blood pressure, which was high, dropped sharply to a point
below the critical region. There resulted a primary increase
in muscular contraction due to the betterment in circulation
caused by the dilation of the vessels before the critical region
was reached. During the time that the pressure was below
the critical region the muscle contraction fell. As the blood
pressure again rose to normal the muscle contraction in-
creased coincidently.

FATIGUE AND ADEENIN 129

of adrenal function, notably Albanese,* and also
Abelous and Langlois,^ inferred from experi-
ments on tbe removal of the glands that the role
they played in the bodily economy was that of neu-
tralizing, destroying or transforming toxic sub-
stances produced in the organism as a result of
muscular or nervous work. It seemed possible that
the metabolites might have a checking or blocking
influence at the junction of the nerve fibres with the
muscle: fibres, and might thus, like curare, lessen the
efficiency of the nerve impulses. Eadwanska's ob-
servation ® that the beneficial action of adrenin is
far greater when the muscle is stimulated through
its nerve than when stimulated directly, and Panel-
la's discovery ^ that adrenin antagonizes the ef-
fect of curare, were favorable to the view that
adrenin improves the contraction of fatigued mus-
cle by lessening or removing a block established by
accumulated metabolites.

The high threshold of fatigued denervated mus-
cle, however, Gruber found was quite as promptly
lowered by adrenin as was that of normal muscles
stimulated through their nerves. Fig. 23 shows
that the height of contraction, also, of the fatigued
muscle is increased when adrenin is administered.
In this experiment the left tibialis anticus muscle
was stimulated directly by thrusting platinum
needle electrodes into it. The peroneus communis
nerve supplying the muscle had been cut and two

130 BODILY CHANGES

centiineters of it removed nine days previous to
the experiment. The rate of stimulation was 120
times per minute and the initial tension of the
spring about 120 grams. At the point indicated

Figure 23. — Top record, blood pressure with
mercury manometer. Middle record, contractions
of a denervated muscle {tibialis anticus) 240 per
per minute against a spring having an initial ten-
sion of 120 grams {peroneus communis nerve was
cut nine days before this record was taken). Bot-
tom record (zero blood pressure), time in half min-
utes. At the point indicated by an arrow 0.1 cubic
centimeter of adrenin (1:100,000) was injected
intravenously.

by the arrow an injection of 0.1 cubic centimeter
of adrenin (1:100,000) was made into a jugular
vein. A fall in arterial pressure from 110 to 86
millimeters of mercury and a simultaneous better-
ment of 20 per cent in the height of contraction

FATIGUE AND ADRENIN ;i31

were obtained. It required four minutes of fatigue
(about 480 contractions) to restore the muscle
curve to its former level. Eesults similar to this
were obtained from animals in which the nerve had
been cut 7, 9, 12, 14, and 21 days. In all instances
the nerve was inexcitable to strong f aradic stimula-
tion.

In Eadwanska's experiments, mentioned above,
the muscle was stimulated directly when the nerve
endings were intact. It seems reasonable to sup-
pose, therefore, that in all cases he was stimulat-
ing nerve tissue. Since a muscle is more irritable
when stimulated through its nerve than when
stimulated directly (nerve and muscle), a slight
change in the irritability of the muscle by adrenin
would naturally result in a greater contraction
when the nerve was stimulated. Panella's results
also are not inconsistent with the interpretation
that the effect of adrenin is on the muscle substance
rather than on the nerve endings. A method which
has long been used to separate muscle from nerve
is that of blocking the nervous impulses by the
drug curare. Gruber found that when curare is in-
jected the threshold of the normal muscle is in-
creased as was to be expected from the removal of
the highly efficient nervous stimulations. And also,
as was to be expected on that basis, curare did not
increase the threshold in a muscle in which the
nerve endings had degenerated. Adrenin antago-

132 BODILY CHANGES

nizes curare with great promptness, decreasing the
heightened threshold of a curarized muscle, in five
minutes or less, in some cases to normal. From
this observation it might be supposed that curare
and fatigue had the same effect, and that adrenin
had the single action of opposing that effect. But
fatigue raises the threshold of a curarized muscle,
and adrenin then antagonizes this fatigue. Lang-
ley ^ has argued that curare acts upon a hypo-
thetical "receptive substance" in muscle. If so,
probably curare acts upon a substance, or at a
point, different from that upon which fatigue acts ;
for, as the foregoing evidence shows, fatigue in-
creases the threshold of a muscle whether deprived
of its nerve supply by nerve section and degenera-
tion or by curare, whereas curare affects only the
threshold of a muscle in which the nerve endings
are normal.^ And since adrenin can oppose the
effects of both curare and fatigue, it may be said
to have two actions, or to act on two different
substances or at two different points in the muscle.
The evidence adduced in the last chapter indi-
cated that the greater "head" of arterial pressure
produced by the more rapid heart beat and the
stronger contraction of many arterioles in times of
great excitement would be highly serviceable to the
organism in any extensive muscular activity which
the excitement might involve. By assuring an
abundant flow of blood through the enlarged ves-

FATIGUE AND ADKENIN 133

sels of the working muscle, the waste products
resulting from the wear and tear in contraction
would be promptly swept away and thus would
be prevented from impairing the muscular effi-
ciency. The adrenin discharge at such times would,
as was pointed out, probably reinforce the effects
of sympathetic impulses. The evidence presented
in this chapter shows that adrenin has also another
action, a very remarkable action, that of restor-
ing to a muscle its original ability to respond to
stimulation, after that has been largely lost by
continued activity through a long period. What
rest will do only after an hour or more, adrenin
will do in five minutes or less. The bearing of this
striking phenomenon on the functions of the or-
ganism in times of great need for muscular activ-
, ity will be considered in a later discussion.

EEFEEENCES

^ Gruber : American Journal of Physiology, 1913, xxxii,
p. 437.

" E. L. Porter : American Journal of Physiology, 1912,
xxxi, p. 149.

^ Cannon and Nice : American Journal of Physiology,
1913, xxxii, p. 55.

* Albanese : Archives Italiennes de Biologie, 1892, xvii,
p. 239.

^ Abelous and Langlois : Archives de Physiologie, 1892,
xxiv, vv- 269-278, 465-476.

"Eadwanska: Anzeiger der Akademie, Krakau, 1910, pp.
728-736. Reviewed in the Centralblatt fiir Biochemie und
Biophysik, 1911, xi, p. 467.

134 BODILY CHANGES

' Panella : Archives Italiennes de Biologie, 1907, xlvii,
p. 30.

* Langley : Proceedings of the Royal Society of London,
1906, Ixxviii, B, p. 181. Journal of PhysiBldgy, 1905-6,
xxxiii, pp. 374-413.

^ See Gruber : American Journal of Physiology, 1914,
xxxiv, p. 89.

CHAPTEE IX

THE HASTENING OF COAGULATION OF BLOOD
BY ADRENIN

The primary value of blood to the body must
have been one of the earliest observations of rea-
soning beings. When we consider the variety of
fundamental services which this circulating fluid
performs — the conveyance of food and oxygen to
all the tissues, the removal of waste, the delivery of
the internal secretions, the protection of the body
against toxins and bacterial invasion, and the dis-
tribution of heat from active to inactive regions —
the view of the ancient Hebrews that the "life of
the flesh is in the blood" is well justified. It is
naturally of the utmost importance that this pre-
cious fluid shall be safeguarded against loss. And
its property of turning to a jelly soon after escap-
ing from its natural channels assures a closure of
the opening through which the escape occurred, and
thus protection of the body from further bleeding.
The slight evidence that adrenin hastens the clot-
ting process has already been hinted at. When we

135

136 BODILY CHANGES

found that adrenin is set free in pain and intense
emotion, it seemed possible that there might exist
in the body an arrangement for making doubly
sure the assurance against loss of blood, a proc-
ess that might nicely play its role precisely when
the greatest need for it would be likely to arise.
It was in 1903, while tracing in dogs the rise and
fall of sugar in the blood after administering
adrenin, that Vosburgh and Richards ^ first noted
that simultaneously with the increase of blood
sugar there occurred more rapid coagulation. In
some cases the diminution was as much as four-
fifths the coagulation time of the control. Since
this result was obtained by painting "adrenalin"
on the pancreas, as well as by injecting it into the
abdominal cavity, they concluded that "the phe-
nomenon appears to be due to the application of
adrenalin to the pancreas." Six years later, dur-
ing a study of the effect of adrenalin on internal
hemorrhage, Wiggers ^ examined incidentally the
evidence presented by Vosburgh and Eichards,
and after many tests on five dogs found "never
the slightest indication that adrenalin, either when
injected or added to the blood, appreciably hast-
ened the coagulation process." In 1911 von den
Velden^ reported that adrenin (about 0.007 mil-
ligram per kilo of body weight) decreased the
coagulation time in man about one-half — an effect
appearing 11 minutes after administration by

FASTER COAGULATION BY ADEENIN 137

mouth, and 85 miniites after subcutaneous injec-
tion. He affirmed also, but without describing the
conditions or giving figures, that adrenin de-
creases coagulation time in vitro. He did not at-
tribute the coagulative effect of adrenin in patients
to this direct action on the blood, however, but to
vasoconstriction disturbing the normal circulation
and thereby the normal equilibrium between blood
and tissue. In consequence, the tissue juices with
their coagulative properties enter the blood, so he
assumed. In support of this theory he offered his
observation that coagulation time is decreased
after the nasal mucosa has been rendered anemic by
adrenin pledgets. Von den Velden's claim ^ for
adrenin given by mouth was subjected to a single
test on man by Dale and Laidlaw,* but their re-
sult was completely negative.

The importance of Vosburgh and Richards' ob-
servation, the thoroughly discordant testimony of
later investigators, as well as the meager and inci-
dental nature of all the evidence that has been ad-
duced either for or against the acceleration of clot-
ting by adrenin, made desirable a further study of
this matter. Especially was this further study de-
sirable because of the discharge of adrenin into
the blood in pain and emotional excitement. Ac-
cordingly, in 1914, H. Gray and I ^ undertook an
investigation of the question. In doing so we em-
ployed cats as subjects. Usually they were quickly

138

BODILY CHANGES

decerebrated under etlier, and tlien continuance of
the drug became unnecessary. Body temperature
was maintained by means of an electric heating
pad. Eespiration proceeded normally except in a
few instances (in which, presumably, there was
hemorrhage into the medulla), when artificial res-
piration had to be given.

The Graphic Method op Measuring the Coagulation
Time

In order to avoid, so far as possible, the personal
element in determining when the blood was clotted.

^

F&

i s

Figure 24. — Diagram of the graphic coagulometer. The can-
nula at the right rests in a water bath not shown in this diagram.
For further description see text.

the blood was made to record its own clotting. The
instrument by means of which this was done was
the graphic coagulometer devised by W. L. Men-
denhall and myself,® and illustrated diagram-
matically in Fig. 24. It consists essentially of a
light aluminum lever with the long arm nearly
counterpoised by a weight W. The long arm is

FASTER COAGULATION BY ADEENIN 139

prevented from falling by a support 8, and is pre-
vented from rising by a horizontal right-angled
rod reaching over the lever at R^ and fixed into the
block B which turns on the axis A. Into the same
block is fixed the vertical rod R^. When this rod
is moved from the post P^, against which it is held
by the weight of the horizontal rod iJ^ towards the
other post P^, the check on the long arm of the
lever is lifted, and if the short arm is heavier, the
long arm will then rise.

The cannula C, into which the blood is received,
is two centimeters in total length and slightly more
than two millimeters in internal diameter. It is
attached by a short piece of rubber tubing to the
tapered glass tube T, five centimeters long and five
millimeters in internal diameter. The upper end
of this tube is surrounded by another piece of rub-
ber which supports the tube when it is slid into the
U-shaped support U, fixed directly below the end
of the short arm of the lever.

By drawing the cannulas from a single piece of
glass tubing and by making the distance from
shoulder to upper end about twelve millimeters,
receptacles of fairly uniform capacity are assured.
All the dimensions, the reach of the rubber con-
nection over the top of the cannula (2-3 milli-
meters), the distance of the upper rubber ring
from the lower end of the glass chamber (4 centi-
meters), etc., were as nearly standard as possible.

140 BODILY CHANGES

A copper wire D, eiglit centimeters long and 0.6
millimeters ia diameter, bent above into a hook
and below into a small ring slightly less than two
millimeters in diameter, is hung in a depression at
the end of the short arm of the lever. The small
ring then rests in the upper part of the cannula
(see Fig. 24). The weight of the copper wire
makes the short arm of the lever heavier than the
long arm by 30 milligrams, when the delicate writ-
ing point is moving over a lightly smoked drum.
Half a dozen of these standard wires are needed.

For accurate determination of the coagulation
time Addis '^ has defined the following conditions
as essential:

1. The blood must always be obtained under the
same conditions.

2. Estimates must all be made at the same tem-
perature.

3. The blood must always come in contact with
the same amount and kind of foreign material.

4. The end point must be clear and definite and
must always indicate the same degree of coagula-
tion.

The precautions taken to fulfill these conditions
were as follows:

1. Drawing the blood. — The blood was taken
from the femoral artery. The artery (usually the
right) was laid bare in the groin and freed from
surrounding tissue. A narrow artery clip, with

FASTER COAGULATION BY ADRENIN 141

each limb enclosed in soft rubber tubing (to pre-
vent injury of the tissues), and with its spring ex-
erting gentle pressure, was placed on the artery
immediately below the deep femoral branch, thus
allowing no blood to stagnate above the clip. Be-
tween the clip and a ligature applied about 1.5
centimeters below, an opening was made. The
blood was carefully milked out of the vessels be-
tween a blunt dissector moved beneath, and a small
forceps, twisted into a pinch of absorbent cotton,
moved above.

The cannula, cleaned in water, alcohol, and ether,
was set in the rubber connection of the glass tube ;
the point of the cannula was then lubricated with
vaseline and slipped into the artery. The pres-
sure of the clip on the artery was next very slightly
released and blood was allowed to flow into the
cannula up to the lower border of the rubber con-
nection. Only a good-sized drop of blood was
needed. Sometimes the blood ran one or two milli-
meters above or below, but without appreciably
changing the result. Since the clip was situated on
the femoral immediately below a branch in which
the circulation persisted, the blood received in the
cannula was always fresh from the moving stream.
As soon as the clip gripped the artery again, the
cannula was slipped out. A helper then promptly
milked the vessel in the manner described above,
and covered it with a pad of absorbent cotton

142 BODILY CHANGES

smeared with, vaseline to prevent drying. There-
by blood was not permitted to stagnate ; and when
a new sample was to be taken, the vessel was clean
and ready for use.

The tip of the cannula was at once plugged by
plunging it into a flat mound of plasticine about
three millimeters high. It was drawn off sidewise
lest the plasticine plug be pulled out again. One
of the copper wires D was now slid into the tube
and cannula, the tube slipped into the U-support,
and the wire lifted and hung on the lever. This
procedure, from the moment blood began to flow
until the wire was hung, consumed usually about
twenty seconds.

2. Uniform temperature. — Under the U-support
was placed a large water bath, in which the can-
nula and the tapering part of the tube were sub-
merged. A thermometer was fixed to the U-sup-
port so that the bulb came near the cannula in the
bath. The water was kept within a degree of 25°
C. This temperature was chosen for several rea-
sons : (a) The cannula has room temperature and
rapidly cools the small volume of blood that enters
it. To heat blood and cannula to body tempera-
ture would take time. A bath near room tempera-
ture, therefore, seems preferable to one near body
temperature, (b) The test of clotting was conveni-
ently made at intervals of a half -minute, and if the
clotting process were hastened by higher tempera-

FASTER COAGULATION BY ADKENIN 143

tures, this interval would become relatively less
exact, (c) A temperature of 25° C. rather than
lower was selected because, as Dale and Laidlaw *
have shown, the coagulation time is much slower
for a given change in temperature below 25°
than for the same change above. And with slow-
ing of the process the end point, when the determin-
ation depends on supporting a weight, is less likely
to be sharp, (d) The researches undertaken with
use of this coagulometer were concerned with fac-
tors hastening the process. For that reason and
for reason (b), a long rather than a short coagula-
tion time for normal conditions was desirable.

3. Uniformity in the amount and kind of con-
tact with foreign surface. — The capacity of the can-
nulas was fairly uniform, as stated above; the
amount received in them was fairly constant ; and
the wire hanging in the blood presented approxi-
mately the same surface in different observations.

A further condition for insuring consistent treat-
ment of the blood in different cases was that of
making the tests for coagulation always at the
same intervals. Below the writing point of the
lever was set an electromagnetic signal E, which
recorded half-minutes. At the moment a record
was made by the signal (see first signal mark. Fig.
25) the clip on the artery was opened, the blood
taken, and the process thus begun. In about 20
seconds the cannula was suspended in the water

144

BODILY CHANGES

as

.a 5
.a I

^^

•43 2

S^
03 o

8|

CO H

s a

c

GO
CQ

CQ S

«o
>-, o

^^

? "t^ *

^•- g.

^ U (U
ffl h S

CI

« ^ a

^-1 CQ

"^S s
<^ ,2

1 CI 2

I

n

g

FASTER COAGULATION BY ADEENIN 145

batli and the wire was hanging on the lever. At the
next record by the signal and at every subsequent
record the vertical rod R^ was pushed with the
index finger from post P^ to post P^ and allowed to
move back. This motion was uniform and lasted
about one second. The check R^ on the long arm of
the lever was thus raised, and as the wire sank in
the blood the writing poiat rose, recording that
coagulation had not taken place (see Fig. 25).

4. Definite end point. — As soon as the blood clot-
ted, the weight of 30 milligrams was supported, and
the failure of the lever to rise to the former height
in the regular time allowed, recorded that the
change had occurred.

Very rarely the swing of the lever would be
checked for a moment and would then begin to
move rapidly, indicating that a strand of fibrin had
formed but not sufficiently strong to support the
weight, and that when the strand broke, the weight
quickly sank in the blood. If this occurred, the
next record almost always was the short line, which
signified that the weight was well supported.

A very slight strand of fibrin was able to pre-
vent the weight from dropping, though at different
times the amount of support differed, as shown by
the varying length of the final lines (compare first
and last series, Fig. 25). These variations are
probably a rough indication of the degree of coagu-
lation. In our experiments, however, the length of

146 BODILY CHANGES

the final line was disregarded, and merely the fact
that the lever failed to swing through its usual
distance was taken as evidence of a clot, and the
consequent short record was taken as the end point.

As soon as this end point was registered, the
tube, wire and cannula were lifted out of the bath ;
the cannula was then separated from the tube and
pulled away from the wire. The clot was thus dis-
closed, confirming the graphic record.

The method, at least when used at half-minute
intervals, did not reveal in all instances the same
degree of clotting. Usually, when the process was
very rapid, the revealed clot was a thick jelly;
whereas, when the process was slow, a strand of
fibrin or at most a small amount of jelly was found.
This difference in the degree of coagulation intro-
duced, of course, an element of inexactness. In our
experiments, however, this inexactness was unfa-
vorable to the result we were seeking for, i. e., the
acceleration of the process — because the jelly is a
later stagfe than the fibrin strand; and since we
nevertheless obtained good evidence of accelera-
tion, -^e did not in these experiments attempt to
determine more accurately differences in the stage
of the clotting process.

5. Cleaning of apparatus. — After the wire waS
removed from the tube, the clot attached to; its
ring-tip was carefully brushed away under Coo^
running water. Under the running water, also, a.

FASTER COAGULATION BY ADRENIN 147

trimmed feather was introduced into the cannula
and the tube to push out the plasticine and to wash
out the blood. Wire, cannula and tube were then
dropped into a beaker receiving running hot water
(about 80° C.) and there allowed to remain for
about five minutes. On removal from this the
parts were shaken free from water, passed through
95 per cent alcohol and again shaken free, passed
through ether and let dry.

By having a half-dozen cannulas and wires of
standard size, it was possible to save trouble by
cleaning a number at one time.

Not infrequently the first few samples of blood
taken from an animal showed rapid or somewhat
irregular rates of clotting. Some causes for these
initial variations will be presented in following
pages. The fairly uniform rate of clotting in any
individual after the initial stage, varied in twenty-
one different animals from an average of 3 to an
average of 10.6 minutes, with a combined average
of 5.9 minutes. The conditions for these variations
among the individuals have not been wholly deter-
mined.

The Effects of Subcutaneous Injections of Adrendt

The first observations were of this class.

Oct. 27. A cat weighing about 3 kilos was given
3 cubic centimeters of adrenin 1 :1,000, i.e., 1 milli-
gram per kilo, under the skin. The animal, in this

148 BODILY CHANGES

instance, was kept in uniform ether anesthesia.
Following is a record showing when blood was
taken, and the coagulation time in each instance :

2.56 — Injection made 3.27 — 3.5 minutes

.59—6 minutes .44—2 "

3.07—5.5 " .55—2.5

.13—5 " 4.07—3

.20—6.5 " .20—2 "

Average 5.7 minutes Average 2.6 minutes

4.44 — 6 minutes
5.00—4.5 "
5.50—5 "

Average 5.2 minutes

In this case the coagulation time remained at its
usual level for about 20 minutes after the subcu-
taneous injection.* Thereafter for about an hour
the coagulation time averaged 45 per cent of its
previous duration. And widely separated tests
made during the following hour indicated that ap-
proximately the initial rate of clotting had been re-
gained.

The rather long period (nearly 30 minutes), in
the case just cited, between the injection and the

* This period is longer than is expected after the subcuta-
neous injection of any drug. As will be shown later, strong
doses of adrenin, if injected rapidly, may not at first shorten
the clotting process. Probably in some instances of subcu-
taneous injection of these strong doses, the drug enters the
circulation more rapidly than in others and in consequence
coagulation is not at first accelerated.

FASTER COAGULATION BY ADRENIN 149

first appearance of rapid clotting was not the rule.
As the following figures show, the coagulation time
may become shortened quite promptly after sub-
cutaneous injection.

Oct. 29. 3.30 — 5.5 minutes 3.53 — 4 minutes '

.36—5.5 " 4.01—3.5

.44 Adrenin, 3 cu- .08—3.5

bic centimeters, .16 — 4.5

1:1,000, injected .23—5

subeutaneously. .30 — 5.5
.46 — 5.5 minutes

In this case nine minutes after the injection the
change in the rate of clotting had begun, and it con-
tinued more rapid for the subsequent half -hour.

We did not attempt to find the minimal subcu-
taneous dose which would shorten clotting. A
dose of 0.01 milligram per kilo, however, has
proved effective, as shown by the following figures :

Feb. 3. 11.34—10 minutes

.45— 9

.50 to .52 Adrenin,
2.8 cubic centimeters,
1 :100,000, injected under
skin of groin in cat
weighing 2.8 kilos.

As will be shown later, the dose in this instance
was ten times the minimal effective intravenous
dose. On the basis of these figures, less than a
milligram of adrenin given subeutaneously would
be necessary to shorten clotting to a marked degree
in a man of average weight (70 kilograms).

.■55—10

minutes

12 .06— 7

it

.14— 4

u

.19— 5.5

u

;31— 6

u

.37— 7

u

;45— 9

il

150 BODILY CHANGES

Not many observations were made by us on the
effects of adrenin administered subcutaneonsly.
The amount reaching the vascular system and the
rate of its entrance into the blood could be so much
more accurately controlled by intravenous than by
subcutaneous introduction that most of our atten-
tion was devoted to the latter method.

The Effects of Intravenous Injections

In this procedure a glass cannula was fastened
in one of the external jugular veins and filled with
the same solution as that to be injected. A short
rubber tube was attached and tightly clamped close
to the glass. Later, for the injection, the syringe
needle was inserted through the rubber and into
the fluid in the cannula, the clip on the vein was
removed, and the injection made.

The solutions employed intravenously were
adrenin 1 :10,000, 1 :50,000, and 1 :100,000, in dis-
tilled water.

The smallest amount which produced any change
in clotting time was 0.1 cubic centimeter of a dilu-
tion of 1 :100,000 in a cat weighing two kilos, a dose
of 0.0005 milligram per kilo. Four tests previous
to the injection averaged 5 minutes, and none was
shorter than 4 minutes. Immediately after the in-
jection the time was 2 minutes, but at the next
test the effect had disappeared. Doubling the
dose in the same cat— i. e., giving 0.2 cubic centi-

FASTEE COAGULATION BY ADEENIN 151

meter (0.001 milligram per kilo) — shortened tlie
coagulation time for about 40 minutes :

Dec. 23. 10 .30—4 minutes

10.53 — 3.5 minutes

.35—4

11 .00—1.5 "

.41—4

.05—1.5

.46 Adrenin, 0.001

.10—3

milligram per

.15—2

kilo.

.20—4

.47 — 2.5 minutes

.26—4.5 "

.50—3

.31—5 "

From 10.47, immediately after the second injec-
tion, till 11.20 the average time for clotting was 2.5
minutes, whereas both before and after this period
the time was 4 minutes or longer. At 11.00 o'clock
and 11.05, when the end point was reached in 1.5
minutes ( a reduction of 63 per cent), a thick jelly
was found on examining the cannula. The changes
in clotting time in this case are represented graph-
ically in Fig. 26.

In another case a dose of 0.0005 milligram per
kilo failed to produce any change, but 0.001 milli-
gram per kilo (0.28 cubic centimeter of adrenin,
1 :100,000, given a cat weighing 2.8 kilos) brought a
sharp decline in the record, as follows :

Jan. 9. 11 .32 — 6 minutes 11.48 — 5.5 minutes

.40—6 " .55^ "

.47 Adrenin, 0.001 12.00—5.5 "

milligram per .06 — 7 "

kilo.

In these instances the animals were decere-
brated. For decerebrate cats, the least amount of

152

BODILY CHANGES

adrenin, intravenously, needed to produce shorten-
ing of coagulation time is approximately 0.001
milligram per kilo.

In the above cases rapid clotting was manifest
directly after minute doses. Larger doses, how-

I0:S0 :40 :£0 11:00 : 10 : 30 :30

Figure 26. — Shortening of coagulation
time after injection of adrenin, 0.2 cubic
centimeter, 1:100,000, (0.001 milligram per
kilo), at 10:46. In this and following Fig-
ures a scale for coagulation time is given in
minutes at the left.

ever, may produce primarily not faster clotting but
slower, and that may be followed in turn by a much
shorter coagulation time. The figures below pre-
sent such an instance :

Nov. 25. 2 .36—3 minutes

3 .00—2.5

minutes

.40—3

.03—1.5

.43 Adrenin, 0.5

05—1.5

cubic centime-

.OY— 2.5

ter, 1:10,000.

.10—1.5

.44 — 4 minutes

.14—1.5

.49—3.5

.16—2.5

.53—1.5

19—3

.55—1.5

.23—3

.58—2

.30—3

FASTER COAGULATION BY ADRENIN 153

This unexpected primary increase of coagula-
tion time, lasting at least six minutes, is in strik-
ing contrast to the later remarkable shortening of
the process from 3 to an average of 1.7 minutes
for more than 20 minutes (see Fig. 27, A).

If a strong solution, i. e., 1 :10,000, is injected
rapidly, the process may be prolonged as above,
but not followed as above by shortening, thus :

Nov. 28. 9 .59—3 minutes

10.14^3.5 minutes

10.03—3

.18—3.5

.08 Adrenin, 0.5

.22—3.5 "

cubic centi-

.26—3 "

meter, 1 :10,-

.29—3 «

000.

,33—3 "

.10 — 3 minutes

There was in this case no decrease in coagulation
time at any test for a half -hour after the injection,
but instead a lengthening (see Fig. 27, B). How-
ell ^ has reported the interesting observation that
repeated massive doses of adrenin given to dogs
may so greatly retard coagulation that the animals
may be said to be hemophilic. These two instances
show that on coagulation large doses have the
contrary effect to small, just as Hoskins ^^ showed
was true for intestinal and Lyman and I ^^ showed
was true for arterial smooth muscle.

In a few experiments the brain and the cord to
midthorax were destroyed through the orbit. Arti-
ficial respiration then maintained the animal in uni-

154

BODILY CHANGES

form condition. Under these circumstances, adre-
nin intravenously had more lasting effects than
when given to the usual decerebrate animals with
intact cord. Fig. 28 illustrates such a case. For
thirty minutes before injection the clotting time*
averaged 5.4 minutes. Then, about ten minutes
after one cubic centimeter of adrenin, 1 :50,000, had

J L

SM

:S0 10:00 :10

:20 ;S0

FiGUBB 27. — A, Primary lengthening followed by
shortening of the coagulation time when adrenin, 0.5
cubic centimeter 1:10,000 (0.05 milligram), was injected
slowly at 2 :43. B, Lengthening of the coagulation time
without shortening when the same dose was injected
rapidly at 10:08.

been slowly injected, clotting began to quicken;
during the next twenty minutes the average was 3.4
minutes, and during the following forty-five min-
utes the average was 1.9 minutes — only 35 per cent
as long as it had been before the injection.

In another case in which the brain and upper
cord were similarly destroyed, the clotting time,
which for a half -hour had averaged 3.9 minutes,
was reduced by one cubic centimeter of adrenin.

FASTEE COAGULATION BY ADEENIN 155

1 :100,000, to an average for the next hour and forty
minutes of 2.3 minutes, with 1.5 and 3 minutes as
extremes. During the first forty minutes of this
period of one hour and forty minutes of rapid clot-
ting all of eight tests except two showed a coagula-
tion time of 2 minutes or less. The explanation of
this persistent rapid clotting in animals with spinal
cord pithed is not yet clear.

As indicated in Figs. 26, 27 and 28, the records
of coagulation show oscillations. Some of these
ups and downs are, of course, within the limits of

tt 1 1 1 1 1 1 1 1 1 r

10:40 :50 11:00 :10 :«0 :30 : 40 :50 12:00 .-10 :S0

Figure 28. — ^Persistent shortening of the coagulation time after
injecting (in an animal with brain and upper cord pithed) adrenin,
1 cubic centimeter, 1:50,000 (0.02 milligram), at 11:01-02. The
dash lines represent averages.

error of the method, but in our experience they
have occurred so characteristically after injection
of adrenin, and so often have appeared in a rough

156 BODILY CHANGES

rhythm, that they have given the impression of be-
ing real accompaniments of faster clotting. It
may be that two factors are operating, one tending
to hasten, the other to retard the process, and that
the equilibrium disturbed by adrenin is recovered
only after interaction to and fro between the two
factors.

The oscillations in coagulation time after the in-
jections suggest that clotting might vary with
changes in blood pressure, for that also commonly
oscillates after a dose of adrenin (see, e. g., Fig.
23). Simultaneous recording of blood pressure
and determining of coagulation time have revealed
that each may vary without corresponding varia-
tion in the other. Withinj)rdinary limits, there-
fore, changes of blood pressure do not change the
rate of clotting.

The Hastening of Coagulation by Adrenin Not a Direct
Effect on the Blood

As previously stated, von den Velden has con-
tended that shortening of coagulation time by adre-
nin is due to exudation of tissue juices resulting
from vasoconstriction. The amount of adrenin
which produces markedly faster clotting in the
cat, is approximately 0.001 milligram per kilo. As
Lyman and I ^^ showed, however, this amount
when injected slowly, as in the present experi-
ments, results in brief vasodilation rather than

FASTEE COAGULATION BY ADRENIN 157

vasoconstriction. Von den Velden's explanation
can therefore not be applied to these experiments.
He has claimed, furthermore, that adrenin added
to blood in vitro makes it clot more rapidly, but,
as already noted, he gives no account of the condi-
tions of his experiments and no figures. It is im-
possible, therefore, to criticise them. His claim,
however, is contrary to Wiggers's ^^ earlier ob-
servations that blood with added adrenin coagulat-
ed no more quickly than blood with an equal
amount of added physiological salt solution. Also
contrary to this claim are the following two experi-
ments : (1) Ligatures were tied around the aorta
and inferior vena cava immediately above the dia-
phragm, and thus the circulation was confined al-
most completely to the anterior part of the animal.
Indeed, since the posterior part ceases to function
in the absence of blood supply, the preparation
may be called an "anterior animal." When such a
preparation was made and 0.5 cubic centimeter of
adrenin, 1:100,000 (half the usual dose, because,
roughly, half an animal), was injected slowly into
one of the jugulars, coagulation was not shortened.
Whereas for a half -hour before the injection the
clotting time averaged 4.6 minutes, for an hour
thereafter the average was 5.3 minutes — a pro-
longation which may have been due, not to any in-
fluence of adrenin, but to failure of the blood to
circulate through the intestines and liver. ^* In an-

158 BODILY CHANGES

other experiment after the gastro-intestinal canal
and liver had been removed from the animal, the
average time for coagulation during twenty-five
minutes before injecting adrenin (0.23 cubic centi-
meter, 1 :100,000, in an animal weighing originally
2.3 kilos) was 5.5 minutes, and during forty min-
utes after the injection it was 6.8 minutes, with no
case shorter than 6 minutes. In the absence of cir-
culation through the abdominal viscera, therefore,
adrenin fails to shorten the clotting time. (2) The
cannulas were filled with adrenin, 1:1,000, and
emptied just before being introduced into the
artery. The small amount of adrenin left on the
walls was thus automatically mixed with the drawn
blood. Alternate observations with these cannulas
wet by adrenin and with the usual dry cannulas
showed no noteworthy distinction.

Feb. 19. 2.21 — 6 minutes, with usual cannula
.30—6.5 "

.36—6.5 " " adrenin

.49—6 « " "

.56—7 " " usual

3.04—6 " " adrenin

The results of these experiments have made it
impossible for us to concede either of von den
Velden's claims, i. e., that clotting occurs faster be-
cause adrenin is added to the blood, or because
adrenin by producing vasoconstriction causes tis-
sues to exude coagulant juices.

Vosburgh and Eichards found that coagulation.

FASTER COAGULATION BY ADEENIN 159

became more rapid as the blood sugar mcreased.
Conceivably, faster clotting might result from this
higher percentage of blood sugar. Against this
assumption, however, is the fact that clotting is
greatly accelerated by 0.001 milligram adrenin per
kilo of body weight, much less than the dose
necessary to increase the sugar content of the
blood.^^ And furthermore, when dextrose (3 cubic
centimeters of a 10 per cent solution) is added to
the blood of an anterior animal, making the blood
sugar roughly 0.3 per cent, the coagulation time
is not markedly reduced. Adrenin ap pears to act,
therefore, in some other way than by increasing
blood^sugar^

Since adrenin makes the blood clot much faster
than normally in the intact animal, and fails to
have this effect when the circulation is confined to
the anterior animal, the inference is justified that
in the small doses here employed adrenin produces
its remarkable effects, not directly on the blood it-
self, not through change in the extensive neuro-
muscular, bony, or surface tissues of the body, but
through some organ in the abdomen.

That exclusion of the liver from the bodily econ-
omy, by ligature of its vessels or by phosphorus
poisoning, will result in great lengthening of the
coagulation time has been clearly shown. .The
liver, therefoxe,-seems^t^#urnish continuously to
l;he blood a factor in the clotting process which is

160 BODILY CHANGES

being continuously destroyed in the body. It is not
unlikely tbat adrenin makes the blood clot more
rapidly by stimulating the liver to discharge this
factor in greater abimdance. But proof for this
suggestion has not yet been established.

EEFEEENCES

^ Vosburgh and Bichards : American Journal of Physi-
ology, 1903, ix, p. 39.

2 Wiggers : Archives of Internal Medicine, 1909, iii,
p. 152.

^ Von den Velden : Miinchener medizinische Wochen-
schrift, 1911, Iviii, p. 187.

* Dale and Laidlaw : Journal of Pathology and Bacteriol-
ogy, 1912, xvi, p. 362.

^ Cannon and Gray : American Journal of Physiology,
1914, xxxiv, p. 321.

^ Cannon and Mendenhall : American Journal of Physi-
ology, 1914, xxxiv, p. 225.

' Addis : Quarterly Journal of Experimental Physiology,
1908, i, p. 314.

* Dale and Laidlaw : Loc. cit., p. 359.

° Howell : American Journal of Physiology, 1914, xxxiii,
p. xiv.

'^'' Hoskins : American Journal of Physiology, 1912, xxix,
p. 365.

'^^ Cannon and Lyman : American Journal of Physiology,
1913, xxxi, p. 376.

'^^ Cannon and Lyman : Loc. cit., p. 381.

^'Wiggers: Loc. cit., p. 152.

1* See Pawlow : Archiv f iir Physiologic, 1887, p. 458.
Bohr : Centralblatt f iir Physiologic, 1888, ii, p. 263. Meek :
American Journal of Physiology, 1912, xxx, p. 173. Gray
and Lunt: Ihid., 1914, xxxiv, p. 332.

''Cannon: American Journal of Physiology, 1914,
xxxiii, p. 396.

CHAPTER X

THE HASTENING OF THE OOAGTJIATION OF
BLOOD IN PAIN AND GEEAT EMOTION

In the foregoing chapter evidence was presented
that the intravenous injection of minute amounts
of adrenin hastens the clotting of blood. The
amounts used did not vary much above or below
the amounts discharged by the adrenal glands after
brief stimulation of the splanchnic nerves, as
found by H. Osgood m the Harvard Laboratory,
and may therefore be regarded as physiological.
Since injected adrenin is capable of shortening the
coagulation time, may not the increased secretion
of the adrenals likewise have that effect? The an-
swer to this question was the object of an investi-
gation by W. L. Mendenhall and myself.^

The blood was taken and its coagulation was re-
corded graphically in the manner already de-
scribed. In some instances the cats were etherized,
in others they were anesthetized with urethane, or
were decerebrated. The splanchnic nerves always
were stimulated after being cut away from connec-

161

162 BODILY CHANGES

tion witli the spinal cord. Sometimes tlie nerves
were isolated unilaterally in the abdomen; some-
times, in order to avoid manipulation of the abdom-
inal viscera, they were isolated in the thorax and
stimulated singly or together. A tetanizing cur-
rent was used, barely perceptible on the tongue
and too weak to cause by spreading any contrac-
tion of skeletal muscles.

Coagulation Hastened by Splanchnic Stimulation

JuJ"

That splanchnic stimulation accelerates the clot-
ting of blood, and that the effects vary in different
animals, are facts illustrated in the following
cases :

Oct. 25. — A cat was etherized and maintained in
uniform ether anesthesia. After forty minutes of
preliminary observation the left splanchnic nerves
were stimulated in the abdomen. Following are
the figures which show the effects on the coagula-
tion time:

3.00-^

minutes

. 03 — 2. 5 minutes

.07—5.5

u

.07—2.5

.14-^

ct

.11—3 "

.32—4.5

«

.16—2 "

.39 to .

40 Stimulation

.20—1.5 "

of left splanchnic.

.23—4

.42—5

minutes

.29—5.5 "

.49—5

iC

.40—5.5 "

.56—2

ti

.50—5 "

4.00—1

a

FASTER COAGULATION IN EMOTION 163

In. this instance at least ten minutes elapsed be-
tween the end of stimulation and the beginning of
faster clotting. The period of faster clotting, how-
ever, lasted for about a half-hour, during which the
coagulation time averaged 2.1 minutes, only forty-
three per cent of the previous average of 4.8 min-
utes. It is noteworthy that the curve (see Fig. 29) ,

Figure 29. — Shortening of coagulation
time after stimulation of the left splanchnic
nerves, 3:39-:40.

while lower, shows oscillations not unlike those
which follow injection of adrenin (see p. 155).

The primary delay of the effect is not always,
indeed it is not commonly, present :

Nov. 6. — A cat was anesthetized (1.40 p.m.)
with urethane, and later (3.05) its brain was
pithed. The following observations on the coagu-
lation time show the prompt effect of splanchnic
stimulation :

164 BODILY CHANGES

3 .36 — 7 minutes

.46—6 "
4 .02 to .05 Stimulation of left splanchnic in abdomen.

.08 — 4 minutes

.10—3 "

,18—3.5 "

.23—6.5 "

In Fig. 30 is presented the original record of the
shortening of the coagulation after stimulation of
the left splanchnic nerve (Nov, 8) in a cat with
brain pithed.

In the foregoing instances the coagulation time
was reduced after splanchnic stimulation to less
than half what it was before. The reduction was
not always so pronounced.

Nov. 7. — A cat* maintained in uniform ether
anesthesia with artificial respiration had the fol-
lowing changes in the clotting time of its blood as
the result of stimulating the left splanchnic nerve
in the thorax :

3 .40 — 5 minutes

4 .06—3.5

minutes

.45—5

.11-4

.51—5.5

.16—3.5

.58 to 4.00 Stimulation of

.21—4

left splanch-

.26—4.5

nic.

.31—5

4.01 — 4.5 minutes

.36—6.5

In this case the average for about fifteen minutes

before stimulation was slightly over five minutes,

* This animal had just passed through a period of excite-
ment with rapid clotting.

FASTEE COAGULATION IN EMOTION 165

01 m

•si
as

si'

o a

Pi

<tco
pro

^ >

<!S

I «

0.2

CO a
lis

iS-3

2a

166 BODILY CHANGES

and for twenty-five minutes thereafter it was four
minutes.

In all cases thus far the period of shortened
coagulation lasted from ten to thirty minutes. In
other cases, however, the effect was seen only in a
single observation. If this had occurred only once
after splanchnic stimulation, it niight be attributed
to accident, but it was not an infrequent result,
e.g.:

Oct. 28. — A cat was etherized and decerebrated,
and the splanchnic nerves were isolated in the
thorax. Following are two instances of brief short-
ening of coagulation after splanchnic stimulation :

3.36 — i.5 minutes 4.07 — i.5 minutes
.42—4.5 " .12—5.5 "
.47 to .49 Splanchnic stim- .19 to .22 Splanchnic stim-
ulation, ulation.
.51 — 4.5 minutes .23 — 3.5 minutes
.57—2 " .27—4 "

4.01—4 « .33—5 "

In the foregoing instance it is noteworthy that
the degree of acceleration is not so great after the
second stimulation of the splanchnics as it was
after the first. This reduction of effect as the
nerves were repeatedly stimulated was frequently
noted. The following case presents another illus-
tration :

Nov. 12. — A cat was etherized (2.35 p.m.) and
the medulla was punctured (piqure) at 3.12. The

FASTEE COAGULATION IN EMOTION 167

operation was without effect. The loss or lessen-
ing of effectiveness on second stimulation of the
left splanchnic nerves is to be compared with the
persistence of effectiveness on the right side :

3.40 — 4.5 minutes 4.34 — 4 minutes

.45—4.5 " .39-^ "

.54 to .56 Stimulation of .44 — 4 "

left splanchnic .48 — 4 "

in abdomen. .55 to .57 Stimulation of
4.00 — 3 minutes right splanoh-

.05—2 " nic.

.10—5.5 " .59—3 minutes

.16—5 " 5.02—2.5 "

.22 to .27 Stimulation of .07—3 "

left splanchnic .11 — 3 "

in abdomen. .15 — 5.5 "

.30 — 4 minutes .22—5.5 "

The experiments above recorded show that
stimulation of the splanchnic nerves results imme-
diately, or after a brief period, in a shortening of
the coagulation time of the blood — an effect which
in different animals varies in duration and intens-
ity, and diminishes as the stimulation is repeated.
The next question was whether this effect is pro-
duced through the adrenal glands.

Coagulation Not Hasten^^ed by So.anc_hnic Stimulation if
THE Adrenal Glands are Absent

The manner in which splanchnic stimulation pro-
duces its effects is indicated in the following ex-
periments :

Nov. 28. — A eat was etherized, and through the

168 BODILY CHANGES

orbit the central nervous system was destroyed to
the midthorax. The blood vessels of the left adre-
nal gland were then quickly tied and the gland
removed. The readings for a half hour before the
left splanchnic nerve was stimulated averaged
seven minutes, then —

4.38 to .40 Stimulation of left splanchnic (glandless).

.42 — Y minutes

.50—7
5.02 to .04 Stimulation of right splanchnic.

.06 — 4 minutes

.10—7

.18—7

.26—7

Dec. 4. — A cat was etherized and pithed through
the orbit to the neck region. The right and left
splanchnic nerves were tied and cut in the thorax.
The left adrenal gland was then carefully removed.
These operations consumed about a half -hour. The
following records show the effect of stimulating
the left and right splanchnic nerves :

4.10 — 5 minutes

5.00—2.5 minutes

.16-4.5

.14—6

li

.25 to .28 Stimulation of

.23 to .25 Stimulation of

left splanchnic

right splanch-

(^landless).

nic.

.30 — 4.5 minutes

.26—6

minutes

.35—4.5 "

.33^.5

a

.40—7.5

.38—3.5

iC

.49 to .51 Stimulation of

.43^.5

.«

right splanch-

.49—5

{(

nic.

.55—6

iC

.55 — 4.5 minutes

FASTER COAGULATION IN EMOTION 169

The results in this experiment are represented
graphically in Fig. 31.

Figure 31. — Results of stimulating the left splanchnic nerves,
4:25-:28, after removal of the left adrenal gland; and of stimu-
lating the right splanchnic nerves, 4:49-:51 and 5:23-:25, with
right adrenal gland present.

Elliott's evidence that in the cat the splanchnic
innervation of the adrenals is not crossed has al-
ready been mentioned. If the gland is removed on
one side, therefore, stimulation of the nerves on
that side causes no discharge from the opposite
gland. As the above experiments clearly show,
splanchnic stimulation on the glandless side results
in. no shortening of the coagulation time ; whereas,
in the same animals, stimulation of the nerves on

170 BODILY CHANGES

the other side (still connected with the adrenal
gland) produces a sharp hastening of the clotting
process.

The splanchnics innervate the intestines and
liver even though the adrenal gland is removed.
The foregoing experiments indicate that the nerve
impulses delivered to these organs do not influence
them in any direct manner to accelerate the speed
of coagulation. Indeed, in one of the experiments
(Dec. 4, see Fig. 31) a high reading about ten min-
utes after splanchnic stimulation on the glandless
side suggests the possibility of an opposite effect.
Direct stimulation of the hepatic nerves on one
occasion was followed by a change of the clotting
time from 4.5, 5, 4.5, 4.5 minutes during twenty-five
minutes before stimulation to 4.5, 7, and 6 minutes
during twenty minutes after stimulation.

Since with the adrenals present stimulation of
hepatic nerves induces alteration of glycogen in the
liver and quick increase of blood sugar,^ just as
splanchnic stimulation does, the failure of the
blood to clot faster after stimulation of the hepatic
nerves confirms the evidence already offered that
faster clotting when adrenin is increased in the
blood is not due to a larger amount of sugar pres-
ent (see p. 159).

The liver and intestines cannot be made to
shorten clotting time by stimulation of their
nerves, but, as has already been shown (see p. 157),

FASTEE COAGULATION IN EMOTION 171

neither can adrenin act by itself to hasten the clot-
ting process. Apparently the effect is produced by
cooperation between the adrenals and the liver
(and possibly also the intestines) . Somewhat simi-
lar cooperation is noted in the organization of
sugar metabolism; splanchnic stimulation in the
absence of the adrenal glands does not increase
blood sugar,^ and in the absence of the liver adre-
nin is without influence.*

The variations of effect noted after splanchnic
stimulation can be accounted for by variations
in the adrenin content of the glands. Elliott ^
found, as previously stated, that animals newly
brought into strange surroundings may have a con-
siderably reduced amount of adrenin in their adre-
nals. The animals used in our experiments had
been for varying lengths of time in an animal
house in which barking dogs were also kept, and
were therefore subject to influences which would be
likely to discharge the glands.

The evidence that stimulation of splanchnic
nerves, with accompanying increase of adrenal
secretion, results in more rapid clotting of blood is
especially interesting in relation to the experiments
previously described, which showed that in pain
and emotional excitement there is an increased
secretion of adrenin into the blood. Does the adre-
nin thus liberated have any effect on the rate of
coagulation ? The observations here recorded were

172 BODILY CHANGES

made in order to obtain an answer to that ques-
tion.

Coagulation Hastened by "Painful" Stimulation

In the experiments on the action of stimuli

which in the unanesthetized animal would cause

pain, it will be recalled that f aradic stimulation of

a large nerve trunk (the stump of the cut sciatic)

Figure 32. — Three shortenings of coagulation time after stimu-
lation of the left sciatic nerve, at 4:23-:25, at 4:45-:50 (stronger),
and at 5:15-:17.

and operation under light anesthesia were the
methods used to affect the afferent nerves. El-
liott® found that repeated excitation of the sci-
atic nerve was especially efficient in exhausting the
adrenal glands of their adrenin content, and also

FASTER COAGULATION IN EMOTION 173

that this reflex persisted after removal of the cere-
bral hemispheres. It was to be expected, there-
fore, that with well-stored glands, sciatic stimula-
tion, even in the decerebrate animal, would call
forth an amount of adrenal secretion which would
decidedly hasten clotting. The following case il-
lustrates such a result :

Dec. 12. — A cat was anesthetized with ether at
3.45 and the left sciatic nerve was bared. Decere-
bration was completed at 3.57. The clotting time
of the blood began to be tested six minutes later :

4 .03 — 4 minutes

4.53 — 2.5 minutes

.08—3.5

.57— Y

.13—3.5

5 .06— Y.5 "

.18—4.5

.15 to .17 Stimulation of

.23 to .25 Stimulation

of

left sciatic.

left sciatic.

5.17 — 4 minutes

4.26—2.5 minutes

.22-4.5 ■ "

.29—3.5

.27—5.5 "

.34-^

.36—5.5 "

.40—5

.46—7 "

.45 to .50 Stimulation of

left sciatic.

The results obtained in this ease, which were
similar to results in other cases, are represented
graphically in Fig. 32. The coagulation time
was becoming gradually more prolonged, but
each excitation of the sciatic nerve was followed
by a marked shortening. The strength of stimu-
lation was not determined with exactness, but it

174 BODILY CHANGES

is worthy of note that the current used in the
first and the third stimulations was weaker than
could be felt on the tongue, whereas that used in
the second was considerably stronger, though it
did not produce reflex spasms.

Mere tying of the nerve is capable of producing
a marked shortening of coagulation, as the follow-
ing figures show :

Oct. 21. — 10.57 cat under ether, and urethane
given :

11.11 — 8.5 minutes

.23—8.5

.32 to .35 Left sciatic bared and tied.

.37 — 1.5 minutes

.41—5.5 "

.50— Y "

12.02—8.5 "

Stimulation of the crural nerve had similar
effects, reducing the clotting time in one instance
from a succession of 3, 3, and 3.5 minutes to 1.5
minutes shortly after the application of the cur-
rent, with a return to 3.5 minutes at the next test.

Operative procedures performed under light
anaesthesia (i. e., with the more persistent reflexes
still present), or reduction of anesthesia soon after
operation, resulted in a remarkable shortening of
the coagulation time :

Nov. 8. — A cat was etherized and tracheoto-
mized. The abdomen was then opened and a liga-
ture was drawn around the hepatic nerves. The

FASTER COAGULATION IN EMOTION 175

operation was completed at 2.25. At 2.50 the
etherization became light and the rate of clotting
began to be faster :

2.50 — 6 minutes 3.15—3.5 minutes

3.00—5.5 " .20—4.5

.10—3.5 " .30—7.5 "

Nov. 11. — A female cat, very quiet, was placed
in the holder at 1.55. The animal was not excited.
At 2.10 etherization was begun; the animal was
then tracheotomized, and the femoral artery was
exposed.

2.21 — 4.5 minutes

.26 — 4.5 " Anesthesia lessened.

.32—3.5 " " light.

.35 Abdomen opened.

.47 — 1.5 minutes.

.52—1

.55 Ligature passed around hepatic nerves.

.57 — 1.5 minutes. Anesthesia light; corneal reflex present.
3.02—3 "

.07 — 3 " Some hepatic nerves cut.

.12 — 4.5 " Rest of hepatic nerves cut.

.22—5 "

The results of this experiment are shown graph-
ically in Fig. 33.

Nov. 13. — A cat was etherized at 1.55, tracheoto-
mized, and the femoral artery laid bare. As soon
as these preparations were completed, the ether
was removed and anesthesia became light. The
blood clotted thus :

176

BODILY CHANGES

.08—6

minutes

.15—4

a

Anesthesia light.

.20—2

u

.24—1

a

Etherization begun again

.27—2.5

u

.30—3.5

u

.35—5.5

a

.50—5.5

u

In the foregoing and in other similar instances,
a condition of surgical injury, whether just made

Figure 33. — Shortening of coagulation
time during an operation under hght anes-
thesia. At 2 :35 the abdomen was opened,
at 2:55 a hgature was passed around the
hepatic nerves.

or being made, was accompanied by more rapid
clotting of blood when the degree of anesthesia was
lessened. This condition was one which, if allowed
to go further in the same direction, would result
in pain. Both direct electrical stimulation and also
surgical operation of a nature to give pain in the
unanesthetized animal result, therefore, in faster
clotting.

FASTER COAGULATION IN EMOTION 177

It is worthy of note that after deeerebration clot-
ting apparently occurred no faster because the ab-
domen had been opened, although in the decere-
brate state etherization was suspended. The
mechanism for reflex control of the adrenals may
not be higher than the corpora quadrigemina, as
Elliott has shown, but the discharge from the
glands seems to be more certain to occur when the
cerebrum is present and is permitted even slightly
to operate.

Coagulation Hastened in Emotional Excitement

The evidence for emotional secretion of the adre-
nal glands has already been presented. As was
noted in my earlier observations on the motions of
the alimentary canal (see p. 14), cats differ widely
in their emotional reaction to being bound ; some,
especially young males, become furious; others,
especially elderly females, take the experience
quite calmly. This difference of attitude was used
with positive results, the reader will recall, in the
experiments on emotional glycosuria ; there seemed
a possibility likewise of using it to test the effect
of emotions on blood clotting. To plan formal ex-
periments for that purpose was not necessary, be-
cause in the ordinary course of the researches here
reported, the difference in effects on the blood be-
tween the violent rage of vigorous young males and
the quiet complacency of old females was early

178

BODILY CHANGES

noted. Indeed, the rapid clotting which, accom-
panied excitement not infrequently made necessary
an annoying wait till slower clotting would permit
the use of experimental methods for shortening the
process.

The animals used on November 11 and 13 (see
pp. 175, 176) are examples of calm acceptance of
being placed on the holder ; and furthermore, these
animals were anesthetized without much dis-
turbance. As the figures indicate, the clotting
from the first occurred at about the average rate.

In sharp contrast to these figures are those ob-
tained when a vigorous animal is angered :

Oct. 30. — A very vigorous eat was placed on the
holder at 9.08. It at once became stormy, snarling,
hissing, biting, and lashing its big tail. At 9.12
etherizing was begun and that intensified the ex-
citement. By 9.15 the femoral artery was tied.
The clotting time of the blood for an hour after the
ether was first given was as follows :

9.18—0.5
.19—1
.22—1
.24—1
.26—1
.28—1.5
.31—1
.33—0.5
.35—0.5
.38—0.5
.39—0.5
.41—1

minute

9.43 — 1 minute
.45—0.5
.49—0.5
.52—0.5
.54—0.5
.57—1
10.00—0.5
.02—0.5
.06—1
.09—0.5
.11—0.5
.13—1

FASTER COAGULATION IN EMOTION 179

Twenty-four observations made during the hour
showed that the clotting time in this enraged ani-
mal averaged three-fourths of a minute and was
never longer than a minute and a half. The clots
were invariably a solid jelly. The persistence of
the rapid clotting for so long a period after anes-
thesia was started may have been in part due to
continued, rather light, etherization, for Elliott ''
found that etherization itself could reduce the
adrenin content of the adrenal glands.

The shortened clotting did not always persist so
long as in the foregoing instance. The brief period
of faster clotting illustrated in the following case
was typical of many :

Nov. 18. — A cat that had been in stock for some
time was placed on the holder at 2.13, and was at
once enraged. Two minutes later etherization was
started. The hairs on the tail were erect. The
clotting was as follows :

2.25 — 1 minute; 2.31 — 4.5 minutes

.27—0.5 " .3Y— 3.5

.28—2 " .47—4.5 "

It seems probable that in this case just as in
some of the cases in which the splanchnic nerves
were stimulated (see p. 166), the adrenals had been
well-nigh exhausted because of the cat's being
caged near dogs, and that the emotional flare-up
practically discharged the glands, for repeated at-

180 BODILY CHANGES

tempts later to reproduce the initial rapid clotting
by stimulation of the splanchnic nerves were with-
out result.

Evidence presented in previous chapters makes
wholly probable the correctness of the inference
that the faster coagulation which follows emotional
excitement is due to adrenal discharge from
splanchnic stimulation. In this relation the effect
of severance of the splanchnics on emotional accel-
eration of the clotting process is of interest. The
following cases are illustrative :

Oct. 29. — A cat was left on the holder for ten
minutes while the femoral artery was uncovered
under local anesthesia. The blood removed was
clotted in a half -minute. The animal was much
excited. It was now quickly etherized and the
brain pithed forward from the neck. The tests
resulted as follows :

10.51 — 1 minute.
■ .53—0.5 "
.55—0.5 "
.5Y— 0.5 "
11.07 Cut left splanchnic.
.12 " right splanchnic.
.21 — 3.5 minutes.
.26—3.5 "

The original record of this case is given in Fig.
34.

Nov. 5. — A cat was etherized at 2.35. At 2.39
artificial respiration by tracheal cannula was be-

FASTER COAGULATION IN EMOTION 181

guQ, the air passing through an ether bottle. The
clotting occurred thus:

2.53 — 1.5 minutes

.57—1.5
3.05—1.5 "

.15—1.5

.25 Both splanchnics cut and tied in thorax.

.35 — 4.5 minutes

.55—4.5 "

Nov. 7. — A cat was etherized at 1.55 under ex-
citement and with tail hairs erect. At 2.13 the ani-

I0:S1

10:53

lOM 10:57

11:21

11:26

Figure 34. — About two-thirds original size. Record of rapid
clotting (less than a half-minute) after emotional excitement. At
11:07 the left, at 11:12 the right splanchnic nerves were out; the
clotting then required 3:5 minutes. The marks below the time
record indicate the moments when the samples were drawn.

mal was showing reflexes,
course of the experiment:

The figures show the

2.15—1.5

minutes

.21—1

.26—1

.31—1

.36—1

.41—1

.46—2

.51—2

3.06—2

3.11 — 2.5 minutes
.26 Cut left splanchnic in

thorax.
.35 Cut right splanchnic in

thorax.
.40 — 5 minutes
.45—5
.51—5.5 "

182 BODILY CHANGES

In this instance the subsequent stimulation of
the splanchnic nerves resulted again in faster clot-
ting — a reduction from 5.5 minutes to 3.5 minutes
(see experiment Nov. 7, p. 164). The results from
this experiment are expressed graphically in Fig.
35.

1 1

s -

1 1

1 1 1 1 1

i ~

8 ""
« —

/

/

1 1

1 1

1 I 1 1 1

2:10 :20 :30 . :40 -.SO 3:00 :10 :iO :30 :40 :«0

Figure 35. — Rapid clotting after emotional excitement, with
slowing of the process when the splanchnic nerves were cut in the
thorax (the left at 3:26, the right at 3:35).

The data presented in this chapter^slioaLJiiat
such stimulation as in the unanesthetized^animal
would cause pain, and also such emotions as Jear
and rage, are capable of greatly shoxtejiing^the
coagulation time of blood. These results are quite
in harmony with the evidence previously offered
that injected adrenin and secretion from the adre-
nal glands induced by splanchnic stimulation
hasten clotting, for painful stimulation and emo-

FASTER COAGULATION IN EMOTION 183

tional excitement also evoke activity of the adre-
nals. Here, then, is another fundamental change
in the body, a change tending to the conservation
of its most important fluid, wrought through the
adrenal glands in times of great perturbation.
This bodily change and the others which occur
under the same circumstances are next to be ex-
amined with reference to their significance.

EEFERENCES

^ Cannon and Mendenhall : American Journal of Physi-
ology, 1914, xxxiv, p. 251.

^ Macleod : Diabetes : its Pathological Physiology, Lon-
don, 1913, pp. 68-Y2.

^ Gautrelet and Thomas : Comptes Eendus, Societe de
Biologie, 1909, Ixvii, p. 233.

* Bang : Der Blutzucker, Wiesbaden, 1913, p. 87.

"Elliott: Journal of Physiology, 1912, xliv, p. 379.

« Elliott : Loc. cit., pp. 406, 407.

' Elliott : Loc. cit., p. 388.

CHAPTER XI

THE UTILITY OF THE BODILY CHANGES IN
PAIN AND GEEAT EMOTION

We now turn from a consideration of the data
secured in our experiments to an interpretation of
the data. One of the most important lessons of ex-
perience is learning to distinguish between the
facts of observation and the inferences drawn from
■those facts. The facts may remain unquestioned;
the explanation, however, may be changed by addi-
tional facts or through the influence of more ex-
tensive views. Having given this warning, I pro-
pose to discuss the bearings of the results reported
in the earlier chapters.

Our inquiry thus far has revealed that the
adrenin secreted by the adrenal glands in times of
stress has all the effects in the body that are pro-
duced by injected adrenin. It plays an essential
role in calling forth stored carbohydrate from the
liver, thus flooding the blood with sugar; it helps
in distributing the blood to the heart, lungs, central
nervous system and limbs, while taking it away

184

UTILITY OF BODILY CHANGES 185

from the inhibited organs of the abdomen; it
quickly abolishes the effects of muscular fatigue ;
and it renders the blood more rapidly coagulable.
These remarkable facts are, furthermore, asso-
ciated with some of the most primitive experiences
in the life of higher organisms, experiences com-
mon to all, both man and beast — the elemental
experiences of pain and fear and rage that come
suddenly in critical emergencies. What is the sig-
nificance of these profound bodily alterations?
What are the emergency functions of secreted
adrenin?

The Keflex Nature of Bodily Responses in Pain and

THE Major Emotions, and the Useful Character

OP Reflexes

The most significant feature of these bodily re-
actions in pain and in the presence of emotion-
provoking objects is that they are of the nature
of reflexes — they are not willed movements, indeed
they are often distressingly beyond the control
of the will. The pattern of the reaction, in these
as in other reflexes, is deeply inwrought in the
workings of the nervous system, and when the
appropriate occasion arises, typical organic re-
sponses are evoked through inherent automatisms.

It has long been recognized that the_ most char-
acteristic feature of reflexes is their "purposive"
nature, or their utility either in preserving the

186 BODILY CHANGES

welfare of the organism or in safeguarding^jt
against injury.. The reflexes of sucking, swal-
lowing, vomiting and coughing, for instance, need
only to be mentioned to indicate the variety of
ways in which reflexes favor the continuance of
existence. When, therefore, these automatic re-
sponses accompanying pain and fear and rage —
the increased discharge of adrenin and sugar — are
under consideration, it is reasonable to inquire
first as to their utility.

Numerous ingenious suggestions have been of-
fered to account for the more obvious changes
accompanying emotional states — as, for example,
the terrifyiag aspect produced by the bristling of
the hair and the uncovering of the teeth in# an
access of rage.^ Tne most widely applicable ex-
planation proposed for these spontaneous reac-
tions is that during the long course of racial
experience they have been developed for quick
service in the struggle for existe^^ Earlier
writers on organic evolution pointed out the antici-
patory character of these responses. According to
Spencer,^ "Fear, when strong, expresses itself
in cries, in efforts to hide or escape, in palpitations
and tremblings ; and these are just the manifesta-
tions that would accompany an actual experience
of the evil feared. The destructive passions are
shown in a general tension of the muscular system,
in gnashing of the teeth and protrusion of the

UTILITY OF BODILY CHANGES 187

claws, in dilated eyes and nostrils, in growls ; and
these are weaker forms of the actions that accom-
pany the killing of prey." /McDougall ^ has de-
veloped this idea systematically and has suggested
that an association has become established between
peculiar emotions and peculiar instinctive reac-
tions ; thus the emotion of fear is associated with
the instinct for flight, and the emotion of anger
or rage with the instinct for fightiag or attack.
Crile * likewise in giving recent expression to
the same view has emphasized the importance
of adaptation and natural selection, operative
through myriads of years of racial experience, in
enabling us to account for the already channeled
responses which we find established in our nervous
organization. And on a principle of "phylogenetic
association" he assumes that fear, born of innu-
merable injuries in the course of evolution, has de-
veloped into portentous foreshadowing of possible
injury and has become, therefore, capable of arous-
ing in the body all the offensive and defensive
activities that favor the survival of the organism.
Because the increase of adrenin and the increase
of sugar in the blood, following painful or strong
emotional experiences, are reflex in character, and
because reflexes as a rule are useful responses,
we are justified in the assumption that under these
circumstances these reactions are useful. What,
then, is their possible value?

188 BODILY CHANGES

In order that these reactions may be iiseful
they must be prompt. Such is the case. Some
observations made by one of my students, Mr. H.
Osgood, show that the latent period of adrenal
secretion, when the splanchnic nerve is stimulated
below the diaphragm, is not longer than 16 sec-
onds ; and Macleod ^ states that within a few min-
utes after splanchnic stimulation the sugar in the
blood rises between 10 and 30 per cent. The two
secretions are, therefore, almost instantly ready
for service.

Conceivably the two secretions might act in con-
junction, or each might have its own function alone.
Thus adrenin might serve in cooperation with
nervous excitement to produce increase of blood
sugar, or it might have that function and other
functions quite apart from that. Before these
possibilities are considered, however, the value of
the increased blood sugar itself will be discussed.

The Utility of the Increased Blood Sugar as a Source of
Muscular Energy

When we were working on emotional glycosuria
a clue to the significance of the increase of sugar in
the blood was found in McDougall's suggestion of
a relation between "flight instinct" and "fear
emotion," and "pugnacity instinct" and "anger
emotion." And the point was made that, since
the fear emotion and the anger emotion are, in

UTILITY OF BODILY CHANGES 189

wild life, likely to be followed by activities (run-
ning or fighting) which require contraction of great
muscular masses in supreme and prolonged strug-
gle, a mobilization of sugar in the blood might be
of signal service to the laboring muscles. Pain —
and fighting is almost certain to involve pain —
would, if possible, call forth even greater muscular
effort. "In the agony of pain almost every muscle
of the body is brought into strong action," Dar-
win ^ wrote, for "great pain urges all animals,
and has urged them during endless generations,
to make the most violent and diversified efforts
to escape from the cause of suffering."*

* It is recognized that both pain and the major emotions
may have at times depressive rather than stimulating effects.
For example, Martin and Lacey have shown (American Jour-
nal of Physiology, 1914, xxxiii, p. 212) that such stimuli as
vpould induce pain may cause a fall of blood pressure, and
they suggest that the rise of blood pressure commonly report-
ed at times of painful experience is due to the psychic dis-
turbance that is simultaneously aroused. Conceivably there
is a relation between recognizing the possibility of escape
(with the psychic consequences of that possibility) and the
degree of stimulating effect. Thus pains originating from
the interior of the body, or from injuries sure to be made
more painful by action, would not likely lead to action. On
the other hand, the whip and spur illustrate the well-known
excitant effect of painful stimuli.

Similarly in the case of the strong emotions, the effect may
be paralyzing until there is a definite deed to perform. Thus
terror may be the most depressing of all emotions, but, as Dar-
win pointed out (Loc. cit., p. 81), "a man or animal driven
through terror to desperation is endowed with wonderful
strength, and is notoriously dangerous in the highest degree."

190 BODILY CHANGES

That muscular work is performed by energy
supplied in carbonaceous material is shown by the
great increase of carbon-dioxide output in severe
muscular work, which may exceed twenty times
the output during rest. Furthermore, the storage
of glycogen in muscle, and the disappearance of
this glycogen deposit from excised muscle stimu-
lated to activity,'^ or its reduction after excessive
contractions produced by strychnine,^ and the
lessened ability of muscles to work if their glyco-
gen store has been reduced,® and the simple
chemical relation between sugar and the lactic acid
which appears when muscles are repeatedly made
to contract, are all indications that carbohydrate
(sugar and glycogen) is the elective source of en-
ergy for contraction. This conclusion is sup-
ported in recent careful studies by Benedict
and Cathcart,^" who have shown that a small but
distinct increase in the ratio between the carbon-
dioxide breathed out and the oxygen breathed in
during a given period (the respiratory quotient)
occurs during muscular work, and that a decrease
in the quotient follows, thus pointing to a larger
proportion of carbohydrate burned during mus-
cular work than before or after — i. e., a call on the
carbohydrate deposits of the body.

Whether circulating sugar can be immediately
utilized by active muscles has been a subject of dis-
pute. The claim of Chauveau and Kaufmann^^

UTILITY OF BODILY CHANGES 191

that a muscle uses about three and a half times
as much blood sugar when active as when rest-
ing, although supported by Quinquaud/^ and
by Morat and Dufourt/^ has been denied by
Pavy,i* who failed to find any difference be-
tween the sugar content of arterial and venous
blood when the muscle was contracting ; and also
by Magnus-Levy/® who has estimated that the
amount of change ia sugar content of the blood
passing through a muscle must be so slight as to
be within the limits of the error of analysis. On
the other hand, when blood or Ringer's solution
is repeatedly perfused through contracting heart
muscle, the evidence is clear that the contained
sugar may more or less completely disappear.
Thus Locke and Eosenheim ^^ found that from
5 to 10 centigrams of dextrose disappeared from
Ringer's solution repeatedly circulated through
the rabbit heart for eight or nine hours. And
recently Patterson and Starling ^'' have shown
that if blood is perfused repeatedly through a
heart-lung preparation for three or four hours,
and the heart is continually stimulated by adrenin
added to the blood, the sugar in the blood wholly
vanishes ; or if the supply of sugar is maintauied,
the consumption may rise as high as 8 milligrams
per gram of heart muscle per hour — about four
times the usual consumption. "When an animal is
eviscerated it may be regarded as a preparation

192 BODILY CHANGES

in whicli the muscles are perfused with their proper
blood, pumped by the heart and oxygenated by
the lungs. Under these circumstances, the per-
centage of sugar in the blood steadily falls,^*
because the utilization by the tissues is not com-
pensated for by further supply from the liver.
Thus, although there may be doubt that analyses
of sugar in the blood flowing into and out from
an active muscle during a brief period can be accu-
rate enough to prove a clear difference, the evi-
dence from the experiments above cited shows that
when the supply of sugar is limited it disappears
to a greater or less degree when passed repeatedly
through muscular organs.

The argument may be advanced, of course, that
the sugar which thus disappears is not directly
utilized, but must first be changed to glycogen.
There is little basis for this assumption. There
is, on the other hand, considerable evidence that
increasing the blood sugar does, in fact, directly
increase muscular efficiency. Thus Locke ^^ proved
that if oxygenated salt solution is perfused
through the isolated rabbit heart, the beats begin
to weaken after one or two hours ; but if now 0.1
per cent dextrose is added to the perfusing liquid,
the beats at once become markedly stronger and
may continue with very slow lessening of strength
as long as seven hours. And Schumberg ^" noted
that when he performed a large amount of gen-

UTILITY OF BODILY CHANGES 193

eral bodily work (thus using up blood sugar)
and then tested flexion of the middle finger in an
ergograph, the ability of the muscle was greater
if he drank a sugar solution than if he drank an
equally sweet solution of "dulcin." He did not
know during the experiment which solution he was
drinking. These observations have been confirmed
by Prantner and Stowasser, and by Frentzel.^^
In experiments on cats, Lee and Harrold ^^ found
that when sugar is removed from the animal by
means of phlorhizin the tibialis anticus is quick-
ly fatigued ; but if, after the phlorhizin treatment,
the animal is given an abundance of sugar and then
submitted to the test, the muscle shows a much
larger capacity for work. All this evidence is,
of course, favorable to the view that circulating
sugar may be quickly utilized by contracting
muscles.

From the experimental results presented above
it is clear that muscles work preferably by utilizing
the energy stored in sugar, that great muscular
labor is capable of considerably reducing the quan-
tity of stored glycogen and of circulating sugar,
and that under circumstances of a lessened sugar
content the increase of blood sugar considerably
augments the ability of muscles to continue con-
tracting. The conclusion seems justified, there-
fore, that the increased blood sugar attendant on
the major emotions and pain would be of direct

194 BODILY CHANGES

benefit to the organism in the strenuous muscular
efforts involved in flight or conflict or struggle to
be free.

The Utility op Increased Adrenin in the Blood as an

Antidote to the Effects op Fatigue

The function which the discharged adrenin itself
might have in favoring vigorous muscular con-
traction has already been suggested in the chapter
on the effect of adrenin in restoring the irritability
of fatigued muscle. Some of the earliest evidence
proved that removal of the adrenal glands has a
debilitating effect on muscular power, and that
injection of adrenal extract has an invigorating
effect. For these reasons it seemed possible that
increased adrenal secretion, as a reflex result of
pain or the major emotions, might act in itself as
a dynamogenic factor in the performance of mus-
cular work. It was on the basis of that possibility
that Nice and I tested the effect of stimulating
the splanchnic nerves (thus causing adrenal secre-
tion), or injecting adrenin, on the contraction of
the fatigued tibialis anticus. We found, as already
described, that when arterial pressure was of nor-
mal height, and was prevented from rising in the
legs while the splanchnic was being stimulated,
there was a distinct rise in the height of contrac-
tion of the fatigued muscle. And we drew the
inference that adrenin set free in the blood may

UTILITY OF BODILY CHANGES 195

operate favorably to the organism by preparing
fatigued muscles for better response to the nervous
discbarges sent forth in great excitement.

This inference led to the experiments by Gruber,
who examined the effects of minute amounts of
adrenin (0.1 or 0.5 cubic centimeter, 1:100,000),
and also of splanchnic stimulation, on the thresh-
old stimulus of fatigued neuro-muscular and mus-
cular apparatus. Fatigue, the reader will recall,
raises the threshold not uncommonly 100 or 200
per cent, and in some instances as much as 600 per
cent. Eest will restore the normal threshold in
periods varying from fifteen minutes to two hours,
according to the length of previous stimulation.
If a small dose of adrenin is given, however, the
normal threshold may be restored in three to five
minutes.

From the foregoing evidence the conclusion is
warranted that adrejiin,. when freely liberated in
the blood, not only aids in bringing out sugar from
the liver's store of glycogen, but also has a remark-
able influence in quickly restoring to fatigued mus-
cles, which have lost their original irritability, the
same readiness for response which they had when
fresh. Thus the adrenin set free iu pain and in
fear and rage would put the muscles of the body
unqualifiedly at the disposal of the nervous sys-
tem; the difficulty which nerve impulses might
have in calling the muscles into full activity would

196 BODILY CHANGES

be practically abolished ; and this provision, along
with the abundance of energy-supplying sugar
newly flushed into the circulation, would give to
the animal in which these mechanisms are most
efficient the best possible conditions for putting
forth supreme muscular efforts.*

The Question Whether Adrenin Normally Secreted
Inhibits the Use of Sugar in the Body

The only evidence opposed to the conclusion
which has just been drawn is that which may be
found in results recently reported by Wilenko. He
injected adrenin into urethanized rabbits, usually
one milligram per kilo body weight, and then found
that the animals did not oxidize any part of an
intravenous injection of glucose. Rabbits supplied
with glucose in a similar manner, but not given
adrenin, have an increased respiratory quotient.
Wilenko ^^ concluded, therefore, that adrenin les-
sens the capacity of the organism to burn carbo-
hydrates. In a later paper he reported that adren-
in, when added, with glucose, to physiological salt
solution (Locke's), and perfused through the iso-
lated rabbit heart, notably increases the use of
sugar by the heart (from 2.2-2.8 to 2.9-4.3 milli-

* If these results of emotion and pain are not "worked ofE"
by action, it is conceivable that the excessive adrenin and
sugar in the blood may have pathological effects. (Cf. Can-
non : Journal of the American Medical Association, 1911, Ivi,
p. 742.)

UTILITY OF BODILY CHANGES 197

grams of glucose per gram of heart muscle per
hour), but that the heart removed after the animal
has received a subcutaneous injection of adrenin
uses much less sugar, only 0.5-1.2 milligrams
per gram per hour. From these results Wilen-
ko ^* concludes that the glycosuria following in-
jection of adrenin is the result of disturbance of
the use of sugar — an effect which is not direct on
the sugar-consuming organ, but indirect through
action on some other organ.

Wilenko's conclusion fails to account readily for
the disappearance of glycogen from the liver in
adrenin glycosuria. Furthermore, Lusk^® has
recently reported that the subcutaneous adminis-
tration of adrenin (one milligram per kilo body
weight) to dogs, simultaneously with 50 grams of
glucose by mouth, interferes not at all with the
use of the sugar — the respiratory quotient remains
for several hours at 1.0 ; i. e., at the figure which
glucose alone would have given. In other words,
Lusk's results with dogs are directly contradictory
to Wilenko's results with rabbits. Nevertheless,
Wilenko's conclusion might be quite true for the
glycosuria produced by adrenin alone (which must
be excessive), and yet have no bearing whatever
on the glycosuria produced physiologically by
splanchnic stimulation, even though some adrenin
is thereby simultaneously liberated.

The amount of injected adrenin used to produce

198 BODILY CHANGES

adrenin glycosuria is enormous. Osgood lias stud-
ied in the Harvard Physiological Laboratory the
effects on blood pressure of alternately stimulating
the left splanchnic nerves (with the splanchnic
vessels eliminated) and injecting adrenin, and by
this method of comparison ^^ has shown that
the amount secreted after five seconds of stimula-
tion varies betweet 0.0015 and 0.007 milligram. If
0.005 milligram is taken as a rather high average
figure, and doubled (for two glands), the amount
would be 0.01 milligram. To produce adrenin gly-
cosuria, an animal weighing two kilos would be
injected with two hundred times this amount. It
is granted that more adrenin would be secreted if
the nerves were stimulated longer than five sec-
onds, and that with injection under the skin or into
the abdominal cavity (to produce glycosuria), the'
amount of adrenin in the blood at one time would
not be so great as if the injection were into a vein ;
but even with these concessions the amount of ad-
renin in the blood, when it has been injected to
produce glycosuria, is probably very much above
the amount following physiological stimulation of
the glands.

Other evidence that the amount of adrenin dis-
charged when the glands are stimulated is not so
great as the amount needed to produce glycosuria
when acting alone is presented in experiments by
Macleod.^'^ He found that if the nerve fibres

UTILITY OF BODILY CHANGES 199

to the liver were destroyed, stimulation of the
splanchnic, which would cause increased adrenal
secretion, did not increase the blood sugar. The
increased blood sugar due to splanchnic stimula-
tion, therefore, is a nervous effect, dependent, to
be sure, on the presence of adrenin in the blood,
but the amount of adrenin present is not in itself
capable of evoking increase.

Furthermore, the increased blood sugar follow-
ing splanchnic stimulation may long outlast the
stimulation period. The adrenals, however, as has
been demonstrated by Osgood, are soon fatigued,
and fail to respond to repeated stimulation. They
seem to be incapable of prolonged action.

Again, as Macleod ^^ has shown, a rise in the
sugar content of the blood can be induced, if the
adrenals are intact, merely by stimulating the
nerves going to the liver. The increased blood
sugar of splanchnic origin, therefore, is not due to
a disturbance of the use of sugar in the body, as
Wilenko claims for the increase after adrenin in-
jection, but is a result of a breaking down of the
stored glycogen in the liver and is of nervous
origin.

We may conclude, therefore, that since the condi-
tions of Wilenko' s observations are not compar-
able with emotional conditions, his inferences are
not pertinent to the present discussion ; that when
both adrenin and sugar are increased in the blood

200 BODILY CHANGES

as a result of excitement, the higlier percentage
of sugar is not due to adrenin inhibiting the use
of sugar by the tissues, and that there is no evi-
dence at present to show that the brief augmenta-
tion of adrenal discharge, following excitement or
splanchnic stimulation, affects in any deleterious
manner the utilization of sugar as a source of en-
ergy. [ Indeed, the observation of Wilenko and of
Patterson and Starling, above mentioned, that ad-
renin increases the use of sugar by the heart, may
signify that a physiological discharge of the ad-
renals can have a favorable rather than an unfa-
vorable effect on the employment of sugar by the
tissues. , ^

The Vascular Changes Produced by Adrenin Eavorable to
Supreme Muscular Exertion

Quite in harmony with the foregoing argument
that sugar and adrenin, which are poured into the
blood during emotional excitement, render the or-
ganism more efficient in the physical struggle for
existence, are the vascular changes wrought by
increased adrenin, probably in cooperation with
sympathetic innervations. The studies of volume
changes of parts of the body, made by Oliver and
Schafer, have already been mentioned. Their ob-
servations, it will be remembered, showed that
injected adrenin drove the blood from the abdom-
inal viscera into the organs called upon in emer-

UTILITY OF BODILY CHANGES 201

gencies — ^into the central nervous system, the
lungs, the heart, and the active skeletal muscles.
The absence of effective vasoconstrictor nerves
in the brain and the lungs, and the dilation of
vessels in the heart and skeletal muscles during
times of increased activity, make the blood supply
to these parts dependent on the height of general
arterial pressure. In pain and great excitement,
as we have already noted, this pressure is likely
to be much elevated, and consequently the blood
flow through the unconstrieted or actually dilated
vessels of the body will be all the more abundant.
Adreniu ha s a well-known stimulating effect on
the isolated heart — causing an increase both in the
rate and the amplitude of cardiac contraction. This
effect accords with the general rule that adrenin
simulates the action of sympathetic impulses. It
is commonly stated, however, that if the heart
holds its normal relations in the body, adrenin
causes slowing of the beat.^" This view is doubt-
less due to the massive doses that have been
employed, which are quite beyond physiological
limits and which induce such enormous increases
of arterial pressure that the natural influence of
adrenin on heart muscle is overcome by mechanical
obstacles to quick contractions and by inhibitory
impulses from the central nervous system. Hos-
kins and Lovellette have recently shown that when
the precaution, is taken to inject adrenin into a vein

202 BODILY CHANGES

in a manner resembling the discharge from the
adrenal glands, not only is there increased blood
pressure, but generally, also, an acceleration of the
pulse.^" At the same time, therefore, that a
greater amount of work, from increased arterial
pressure, is demanded of the heart, blood is de-
livered to the heart in greater abundance, and the
muscle is excited to more rapid and vigorous pul-
sations. The augmentation of the heart beat is
thus coordinate with the other adaptive functions
of^the adrenal glands in great emergencies.

The Changes in Eespiratory Functon Also Favorable
TO Great Effort

The urgent need in struggle or flight is a gen-
erous supply of oxygen to oxidize the metabolites
of muscular contraction, and a quick riddance of
the resultant carbon-dioxide from the body. The
moment vigorous exercise is begun the breathing
at once changes so as to bring about a more thor-
ough ventilation of the lungs. And one of the most
characteristic reactions of animals in pain and
emotional excitement is deep and rapid respiration.
Again the reflex response is precisely what would
be most serviceable to the organism in the stren-
uous efforts of fighting or escape that might accom-
pany or follow distress or fear or rage. It is
known that by such forced respirations the carbon-
dioxide content of the blood can be so much re-

UTILITY OF BODILY CHANGES 203

duced that the need for any breathing whatever
may be deferred for as much as a minute or
even longer.^^ And Douglas and Haldane ^^ have
found that moderately forced breathing for three
minutes previous to severe muscular exertion re-
sults in greatly diminishing the subsequent res-
piratory distress, as well as lessening the amount
of air breathed and the amount of carbon-dioxide
given off. Furthermore, the heart beats less rap-
idly after the performance and returns more
quickly from its increased rate to normal. The
forced res pira tions in deeply emotional experi-
ences can be interpreted, therefore, as an antici-
patory reduction of the carbon-dioxide in the blood,
a preparation for the augmented discharge of
carbon-dioxide into the blood as soon as great
muscular exertion begins.*

As the air moves to and fro in the lungs with
each respiration, it must pass through the fine
divisions of the air tubes or bronchioles. The
bronchioles are provided with smooth muscle,
which, in all probability, like smooth muscle else-
where in the body, is normally held in a state of

* The excessive production of heat in muscular work gives
rise to sv^eating. The evaporation of sweat helps to keep the
body temperature from rising unduly from the heat of exer-
tion. Again in strong emotion and in pain the "cold sweat"
that appears on the skin may be regarded as a reaction
anticipatory of the strenuous muscular movements that are
likely to ensue.

204 BODILY CHANGES

tonic contraction. When this tonic contraction is
much increased, as in asthma, breathing becomes
difficult, and even with the body at rest unusual
effort is then required to maintain the minimal
necessary ventilation of the lungs. During stren-
uous exertion, with each breath the air must rush
through the bronchioles in greatly increased vol-
ume and speed. Thus in a well person "winded"
with running, for example, the bronchioles might
become relatively too small for the stream of air,
just as they are too small in a person ill with
asthma. And then some extra energy would have
to be expended to force the air back and forth with
sufficient rapidity to satisfy the bodily needs. It
is probable that even under the most favorable con-
ditions, the labored breathing in hard exercise in-
volves to some degree the work of accelerating the
tidal flow of the respiratory gases. This extra
labor would obviously be reduced, if the tonic con-
traction of the ring-muscles in the wall of the
bronchioles was reduced, so that the tubules were
enlarged. It has been shown by a number of in-
vestigators, who have used various methods, that
adrenin injected into the blood stream has as one
of its precise actions the dilating of the bronchi-
oles.^^ The adrenin discharged in emotional ex-
citement goes to the lungs before entering into
relation with any other organ except the right
heart chamber ; it may, therefore, have as its first

UTILITY OF BODILY CHANGES 205

effect the relaxation of the smooth muscles of the
lungs. This would be another very direct means
of rendering the organism more efficient when
fierce struggle calls for a bounteous supply of fresh
air and a speedy discharge of the carbonaceous
waste.

Effects Produced in Asphyxia Similar to those Produced
IN Pain and Excitement

All the bodily responses occurring in pain and
emotional excitement have thus far been consid-
ered as anticipatory of the instinctive acts which
naturally follow. And as we have seen, these re-
sponses can reasonably be interpreted as prepar-
atory to the great exertions which may be de-
manded of the organism. This interpretation of
the facts is supported by the discovery that a
mechanism exists whereby the changes initiated
in an anticipatory manner by emotional excite-
ment are continued or perhaps augumented by the
exertion itself.

Great exertion, such as might attend flight or
conflict, would result in an excessive production of
carbon-dioxide. Then, although respiratory and
circulatory changes of emotional origin may have
prepared the body for struggle, the emotional pro-
visions for keeping the working parts at a high
level of efficiency may not continue to operate, or

206 BODILY CHANGES

they may not be adequate. If there is painful gasp-
ing for breath in the course of prolonged and vig-
orous exertion, or for a considerable period after
the work has ceased, a condition of partial
asphyxia has evidently been induced. This condi-
tion, as everyone knows, is distinctly unfavorable
to further effort. But the asphyxia itself may act
as a stimulus.^*

In our examination of the influence of various
conditions on the secretion of the adrenal glands,
Hoskins and I ^^ tested the effects of asphyxia.
By use of the intestinal segment as an indicator we
compared the action of blood, taken as nearly si-
multaneously as possible from the vena cava above
the adrenal vessels and from the femoral vein be-
fore asphyxia, with blood taken from the same
sources after asphyxia had been produced. The
femoral venous blood after passing the capillaries
of the leg thus acted as a standard for the same
blood after receiving the contribution of the
adrenal veins. Asphyxia was caused by covering
the tracheal cannula until respiration became
labored and slow, but capable of recovery when air
was admitted. It may be regarded, therefore, as
not extreme.

The results of the degree of asphyxia above
described are shoAvn by graphic record in Fig. 36.
Blood taken from the vena cava and from the
femoral vein before asphyxia ("normal") failed to

UTILITY OF BODILY CHANGES 207

cause inhibition of the contractions. Blood taken
from the femoral vein after asphyxia produced al-
most the same effect as blood from the same vein
before; asphyxia, therefore, had wrought no
change demonstrable in the general venous flow.

FiGTiKE 36. — Adrenal secretion produced by as-
phyxia. At 1 normal vena-cava blood applied,
at 2 removed. At 3 normal blood from femoral
vein applied, at 4 removed. At 5 blood from
femoral vein after asphyxia applied, at 6 re-
moved. At 7 blood from the vena cava after
asphyxia applied. Time, half-minutes.

Blood taken from the vena cava after asphyxia
had, on the contrary, an effect markedly unlike
blood from the same region before (compare the
record after 1 and after 7, Fig. 36)— it caused the

208 BODILY CHANGES

typical inhibition which indicates the presence of
adrenal secretion.*

That the positive result obtained in moderate
asphyxia is not attributable to other agencies in
the blood than adrenin is indicated by the failure
of asphyxial femoral blood to cause inhibition,
while vena-cava blood, taken almost simultane-
ously, brought about immediate relaxation of the
muscle. The conclusion was drawn, therefore,
that asphyxia results in increased secretion of the
adrenal glands.

This conclusion has been supported by Bor-
berg and Fridericia,^® and also by Starkenstein,^''
who found that an increase of carbon-dioxide in
the blood lessens the adrenin in the adrenal me-

* This positive result might suggest that the comparison of
both femoral and vena-cava blood under each condition was
unnecessary, and that a comparison merely of vena-cava
blood before and after asphyxia would be sufficient. Positive
results were indeed thus secured, but they occurred even
when the adrenal glands were carefully removed and extreme
asphyxia (i. e., stoppage of respiration) was induced. That
the blood may contain in extreme asphyxia a substance or
substances capable of causing inhibition of intestinal con-
tractions was thus demonstrated. In one instance, after the
blood was proved free from adrenin, the aorta and vena cava
were tied close below the diaphragm, and the carotids were
tied about midway in the neck. Extreme asphyxia was
produced (lasting five minutes). Blood now taken from the
heart caused marked inhibition of the beating intestinal
segment. Probably, therefore, the inhibitory action of blood
taken from an animal when extremely asphyxiated cannot be
due to adrenin alone.

UTILITY OF BODILY CHANGES 209

dulla. And recently Czubalski ^» also has inferred,
from the rise of blood pressure in asphyxia when
the adrenals are intact and the absence of the rise
if the adrenals are removed, that asphyxia sets
free adrenin in the blood.

Asphyxiajike_£ain and excitement, not only lib-
erates adrenin,J)uJt,jLS,migh,irbe inferred from that
fact^_also_mobilizes__sng_ar.i® And, furthermore,
Starkenstein *" has shown that the asphyxia due
to carbon-monoxide poisoning is not accompanied
by increased blood sugar if the adrenal glands have
been removed.

iB-caaa-slrongLemotions are followed by vigor-
ous exertions, therefore, asphyxia is likely to
result, and this will act in conjunction with the
emotional excitement and, pain, or perhaps in con-
tinuation of the influences of these states, to bring
forth still more adrenal discharge and still further
output of sugar from the Jiver. And these in turn
would serve the laboring muscles in the manner
already described. This suggestion is in accord
with Macleod's *^ that the increased freeing of
glycogen from the liver produced by muscular ex-
ercise is possibly associated with increased carbon-
dioxide in the blood. And it also harmonizes with
Zuntz's statement *^ that the asphyxia of great
physical exertion may call out sugar to such a de-
gree that, in spite of the increased use of it in the
active musdes, glycosuria may ensue.

210 BODILY CHANGES

The evidence previously adduced that adrenin
causes relaxation of the smooth muscle of the
bronchioles, taken in conjunction with the evidence
that adrenal secretion is liberated in asphyxia, sug-
gests that relief from difficult breathing may thus
be automatically provided for in the organism.
The well-known phenomenon of "second wind" is
characterized by an almost miraculous refreshment
and renewal of vigor, after an individual has per-
sisted in violent exertion in spite of being "out of
breath." It seems not improbable that this phe-
nomenon, for which many explanations have been
offered, is really due to setting in operation the
supporting mechanism which, as we have seen,
plays so important a role in augmenting bodily
vigor in emotional excitement. The release of
sugar and adrenin, the abundance of blood flow
through the muscles — supplying energy and les-
sening fatigue — and the relaxation of the bronchi-
olar walls, are all occurrences which may reason-
ably, be regarded as resulting from asphyxia. And
when they take place they doubtless do much to
abolish the distress itself by which they were occa-
sioned. According to this explanation "second
wind" would consist in the establishment of the
same group of bodily changes, leading to more
efficient physical struggle, that are observed in
pain and excitement.

UTILITY OF BODILY CHANGES 211

The Utility of Eapid Coagulation in Pretentinq
Loss OP Blood

The increase of blood sugar, the secretion of
adrenin, and the altered circulation in pain and
emotional excitement have been interpreted in the
foregoing discussion as biological adaptations to
conditions in wild life which are likely to involve
pain and emotional excitement, i. e., the necessities
of fighting or flight. T^e_mQxe-j:apid-clat.ting of
bloodunder^ these same circums tances may also be
regarded as an adaptive pr oce ss, useful to the or-
ganism. The importance-of eonserving the blood,
especially in the struggles of mflrtal combat, needs
no argument. The effect of local injury ia favor-
ing the formation of a clot to seal the opened ves
sels is obviously adaptive in protecting the organ-
ism against hemorrhage. The injury that causes
opening^J)lgod-Vjessels^,'£owever, is, if extensive,
likely also to produce pain. And, as already
shown, conditions^roducing pain increase adrenal
secretion and hasten coagulation. Thus injury
would be made less dangerous as an occasion for
serious hemorrhage by two effects which the in-
jury itself produces in the body — the local effect
on clotting at the region of injury and the general
effect on the speed of clotting wrought by reflex
secretion of adrenin.

According to the argument here presented the
strong emotions, as fear and anger, are rightly

212 BODILY CHANGES

interpreted as the concomitants of bodily changes
which may be of utmost service in subsequent ac-
tion. These bodily changes are so much like those
which occur in pain and fierce struggle that, as
early writers on evolution suggested, the emotions
may be considered as foreshadowing the suffering
and intensity of actual strife. On this general
basis, therefore, the bodily alterations attending
violent emotional states would, as organic prepara-
tions for fighting and possible injury, naturally
involve the effects which pain itself would pro-
duce. And increased blood sugar, increased
adrenin, an adapted circulation and rapid clotting
would all be favorable to the preservation of the
organism that could best produce them.

EEFEEENOES

^ See Darwin : Expression of Emotions in Man and Ani-
mals, New York, 1905, pp. 101, 117.

^ Spencer : Principles of Psychology, London, 1855.

^ McDougall : Introduction to Social Psychology, London,
1908, pp. 49, 59.

* Crile : Boston Medical and Surgical Journal, 1910,
clxiii, p. 893.

^ Macleod : Diabetes, etc., p. 80.

^ Darwin : Loc. cit.j p. 72.

^ Nasse : Archiv f iir die gesammte Physiologic, 1869, ii, p.
106; 1877, xiv, p. 483.

^ Frentzel : Archiv f iir die gesammte Physiologie, 1894,
Ivi, p. 280.

® Zuntz : Oppenheimer's Handbuch der Biochemie, Jena,
1911, iv (first half), p. 841.

UTILITY OF BODILY CHANQES 213

1° Benedict and Oathcart: Muscular Work, a Metabolic
Study, Washington, 1913, pp. 85-87.

^^ Chauveau and Kaufmann : Comptes Eendus, Academie
des Sciences, 1886, ciii, p. 1062.

^^ Quinquaud : Comptes Eendus, Societe de Biologie, 1886,
xxxviii, p. 410.

1^ Morat and Duf ourt : Archives de Physiologie, 1892,
xxiv, p. 327.

^* Pavy : The Physiology of the Carbohydrates, London,
1894, p. 166.

^^ Magnus-Levy : v. Noorden's Handbuch der Pathologic
des Stoffwechsels, 1906, i, p. 385.

^^ Locke and Rosenheim : Journal of Physiology, 1907,
xxxvi, p. 211.

^^ Patterson and Starling : Journal of Physiology, 1913,
xlvii, p. 143.

'^^ See Macleod and Pearce : American Journal of Physi-
ology, 1913, xxxii, p. 192. Pavy and Siau : Journal of Physi-
ology, 1903, xxix, p. 375. Macleod: American Journal of
Physiology, 1909, xxiii, p. 278.

" Locke : Centralblatt fiir Physiologie, 1900, xiv, p. 671.

2" Schumberg : Archiv fiir Physiologie, 1896, p. 537.

21 Frentzel : Archiv fiir Physiologie, 1899, Supplement
Band, p. 145.

22 Lee and Harrold : American Journal of Physiology,
1900, iv, p. ix.

23 Wilenko : Biochemische Zeitschrift, 1912, xlii, p. 58.

2* Wilenko : Archiv fiir experimentelle Pathologie und
Pharmakologie, 1913, Lxxi, p. 266.

2^ Lusk : Proceedings of the Society for Experimental
Biology and Medicine, 1914, xi, p. 49. Also Lusk and Eiche:
Archives of Internal Medicine, 1914, xiii, p. 68.

2« See Elliott: Journal of Physiology, 1912, xliv, p. 376.

2^ Macleod: Diabetes, etc., pp. 64-73.

28 Macleod: Diabetes, etc., pp. 68-72.

29 See Biedl : Die Innere Sekretion, 1913, i. p. 464.

3" Hoskins and Lovellette : Journal of the American Med-
ical Association, 1914, Ixiii, p. 317.

214 BtBILY CHANGES

^^ See Haldane and Priestley : Journal of Physiology,
1905, xxxii, p. 255.

^^ Douglas and Haldane : Journal of Physiology, 1909,
xxxix, p. 1.

^^ See Januschke and Pollak : Archiv fiir experimentelle
Pathologie und Pharmakologie, 1911, Ixvi, p. 205. Trendelen-
burg : Zentralblatt fiir Physiologie, 1912, xxvi, p. 1. Jackson :
Journal of Pharmacology and Experimental Therapeutics,
1912, iv, p. 59.

^* Cf. Hoskins and McClure : Archives of Internal Medi-
cine, 1912, X, p. 355.

^' Cannon and Hoskins : American Journal of Physiology,
1911, xxix, p. 275.

'^ Borberg : Skandinavisches Archiv fiir Physiologie, 1913,
xxviii, p. 125.

" Starkenstein : Zeitschrift fiir experimentelle Pathol-
ogie und Therapie, 1911, x, p. 95.

^^ Czubalski : Zentralblatt fiir Physiologie, 1913, xxvii,
p. 580.

^^ For evidence and for references to this literature, see
Bang : Der Blutzucker, Wiesbaden, 1913, pp. 104-108.

*" Starkenstein : Loc. cit., p. 94.

*^ Macleod : Diabetes, etc., p. 184.

*^ Zuntz : Loc. cit., p. 854.

CHAPTER XII

THE ENEEGIZING INFLUENCE OF EMOTIONAL
EXCITEMENT

The close relation between emotion and mnscu-
lar action has long been perceived. As Sher-
rington ^ has pointed out, "Emotion 'moves' ns,
hence the word itself. If developed in intensity, it
impels toward vigorous movement. Every vigor-
ous movement of the body . . . involves also
the less noticeable cooperation of the viscera, es-
pecially of the circulatory and respiratory. The
extra demand made upon the muscles that move
the frame involves a heightened action of the
nutrient organs which supply to the muscles the
material for their energy." The researchl^s here
reported have revealed a number of unsuspected
ways in which muscular action is made more effi-
cient because of emotional disturbances of the
viscera. Every one of the visceral changes that
have been noted— the cessation of processes in the
alimentary canal (thus freeing the energy supply,
for other parts) ; the shifting of blood from the

215

216 BODILY CHANGES

abdominal organs, whose activities are deferable,
to the organs immediately essential to muscular
exertion (the lungs, the heart, the central nervous
system) ; the increased vigor of contraction of the
heart ; the quick abolition of the effects of muscu-
lar fatigue ; the mobilizing of energy-giving sugar
in the circulation — every one of these viscera]
changes is directly serviceable in making the or-
ganism more effective in the violent display of
energy which fear or rage or pain may involve.

"Eeservoirs of Power"

That the major emotions have an energizing
effect has been commonly recognized.* Darwin
testified to having heard, "as a proof of the
exciting nature of anger, that a man when ex-
cessively jaded will sometimes invent imaginary
offences and put himself into a passion, uncon-
sciously for the sake of reinvigorating him-
self ; and," Darwin ^ continues, "since hearing
this remark, I have occasionally recognized its full
truth." Under the impulse of fear also, men have
been known to achieve extraordinary feats of
running and leaping. McDougall * cites the in-

* Russell (The Pima Indians, United States Bureau of
Ethnology, 1908, p. 243) relates a tale told by the Indians to
their children, in which an injured coyote was chasing some
quails. "Finally the quails got tired," according to the
story, "hut the coyote did not, for he was angry and did not
feel fatigue."

ENEEGIZING INFLUENCE 217

stance of an athlete who, when pursued as a boy
by a savage animal, leaped over a wall which he
could not again "clear" until he attained his full
stature and strength. The very unusual abilities,
both physical and mental, which men have exhib-
ited in times of stress were dealt with from the
psychological point of view by William James *
in one of his last essays. He suggested that in
every person there are "reservoirs of power"
which are not ordinarily called upon, but which
are nevertheless ready to pour forth streams of
energy if only the occasion presents itself. These
figurative expressions of the psychologist receive
definite and concrete exemplification, so far as the
physical exhibitions of power are concerned, in
the highly serviceable bodily changes which have
been described in the foregoing chapters.

It would doubtless be incorrect to attempt to
account for all the increased strength and tireless
endurance, which may be experienced in periods
of great excitement, on the basis of abundant sup-
plies provided then for muscular contraction, and
a special secretion for avoiding or abolishing the
depressive influences of fatigue. Tremors, mus-
cular twitchings, the assumption of characteristic
attitudes, all indicate that there is an immensely
augmented activity of the nervous system — an ac-
tivity that discharges powerfully even into parts
not directly concerned in struggle, as, for exam-

218 BODILY CHANGES

pie, into the muscles of voice, causing peculiar
cries or warning notes; into the muscles of the
ears, drawing them back or causing them to stand
erect, and into the small muscles about the lips,
tightening them and revealing the teeth. The
typical appearances of human beings, as well as
lower animals, when in the grip of such deeply
agitating emotions as fear and rage, are so well
recognized as to constitute a primitive and com-
mon means of judging the nature of the experience
through which the organism is passing. This "pat-
tern" response of the nervous system to an emo-
tion-provoking object or situation is probably
capable of bringing into action a much greater
number of neurones in the central nervous system
than are likely to be concerned in even a supreme
act of volition. The nervous impulses delivered to
the muscles, furthermore, operate upon organs
well supplied with energy-yielding material and
well fortified by rapidly circulating blood and by
secreted adrenin, against quick loss of power be-
cause of accumulating waste. Under such circum-
stances of excitement the performance of extraor-
dinary feats of strength or endurance is natural
enough.*

* If individual neurones obey the law of either supreme ac-
tion or inaction, the "all-or-none law," the only means of
securing a graded response is through variation of the number
of neurones engaged in action — the more, the greater the re-
sulting manifestation of strength.

ENEEGIZma INFLUENCE 219

In connection with the conception that strong
emotion has a dynamogenic value, it is of interest
to note that on occasions when great demands are
likely to be placed on the neuro-muscular system in
the doing of unusual labors, emotional excitement
is not uncommonly an accompaniment. In order
to emphasize points in the argument developed
thus far, I propose to cite some examples of the
association of emotional excitement with remark-
able exhibitions of power or resistance to fatigue.

The Excitements and Energies of Competitive Sports

Already in an earlier account (see p. 75) I have
mentioned finding sugar in the urine in approxi-
mately fifty per cent of a group of college football
players after the most exacting game of the sea-
son's play. As is well understood, such games are
heralded far and wide, loyal supporters of each
college may travel hundreds of miles to attend the
contest, enthusiastic meetings of undergraduate
students are held in each college to demonstrate
their devotion to the team and their confidence in
its prowess — indeed, the arguments for victory,
the songs, the cheering, are likely to be so disturb-
ing to the players, that before an important con-
test they are not infrequently removed from
college surroundings in order to avoid being over-
wrought when the contest comes.

On the day of the contest the excitement is,n£ul-

220 BODILY CHANGES

tiplied manyfold. There is practically a holiday
in college and to a large extent in the city as well.
The streets are filled with eager supporters of
each team as the hosts begin to gather at the field.
As many as 70,000 spectators may be present, each
one tense and strongly partisan. The student
bands lead the singing, by thousands of voices,
of songs which urge to the utmost effort for the
college ; and, in anticipation, these songs also cele-
brate the victory.

Into the midst of that huge, cheering, yelling,
singing, flag-waving crowd, the players are wel-
comed in a special outburst of these same demon-
strations of enthusiasm. Soon the game begins.
The position of every player is known, if not be-
cause of previous acquaintance and recognition,
because card-diagrams give the information.
Every important play is seen by the assembled
thousands, and the player who makes it is at once
announced to all, and is likely to be honored by his
multitudinous college mates in a special cheer,
ending in his name. Any player who, by infrac-
tion of the rules or failure to do his part, loses
ground gained by his team is also known. The man
who is "played out" in efforts to win for his team
and college, and consequently has to leave the field,
is welcomed to the side lines by acclamations
suited for a great hero. In short, every effort is
made, through the powerful incentives of censure

ENERGIZING INFLUENCE 221

and a flaunting recognition, to make eaeli member
of the team realize vividly his responsibility, both
personal and as one of a group, for the supreme,
all-important result — victory for his college.

This responsibility works tremendously on the
emotions of the players. In the dressing room -
before a critical contest I have seen a "gridiron
warrior," ready in canvas suit, cleated shoes, and
leather helmet, sitting grimly on a bench, his fists
clenched, his jaws tight, and his face the color of
clay. He performed wonderfully when the game
began, and after it was over there was a large per-
centage of sugar in his urine ! Probably no sport
requires a more sustained and extreme display of
neuro-muscular effort than American football. P-'^.
And from the foregoing description of the condi-
tions that surround the contests it is easy to real-
ize that they conspire to arouse in the players ex-
citements which would bring forth very efficiently
the bodily reserves for use in the fierce struggle
which the game requires.

What is true of football is true, though perhaps
to a less degree, of the racing sports, as running
and rowing. Again great multitudes attend the
events, the contests are followed closely from be-
ginning to end, and as the goal is approached the
cheering and cries for victory gather in volume
and intensity as if arranged for a thrilling climax.
The whole setting is most highly favorable to the

222 BODILY CHANGES

dramatic development of an acme of excitement
as the moment for the last desperate effort to win
is put forth.

Frenzy and Endurance in Ceremonial and Other Dances

Dancing, which formed a significant feature of
primitive rituals, has always been accompanied by
exciting conditions, and not unusually was an ex-
hibition of remarkable endurance. In the trans-
fer of the Ark to Zion there were processions and
sacrifices, and King David "danced before the
Lord with all his might." Mooney ® in his ac-
count of dances among the American Indians tells
of a young man who in one of the ceremonials
danced three days and nights without food, drink
or sleep. In such a terrible ordeal the favoring
presence of others, who through group action help
to stimulate both the excitement and the activities,
must be an important element in prolonging the
efforts of the individual.

In the history of religious manias " there are
many instances of large numbers of people becom-
ing frenzied and then showing extraordinary en-
durance while dancing. In 1374 a mania broke
forth in Germany, the Netherlands and France, in
which the victims claimed to dance in honor of
Saint John. Men and women went about dancing
hand in hand, in pairs, or in a circle, on the streets,
in the churches, at their homes, or wherever they

ENERGIZING INFLUENCE 223

might be, hour after hour without rest. While
dancing they sang, uttered cries, and saw visions.
Whole companies of .these crazy fanatics went
dancing along the public roads and into the cities,
until they had to be interfered with.

In 1740 an extraordinary sect, known as the
"Jumpers," arose in Wales. According to the
description given by Wesley, their exercises were
not unlike those of certain frenzied states among
the Indians. "After the preaching was over,"
Wesley ^ wrote, "anyone who pleased gave out
a verse of a hymn; and this they sung over and
over again, with all their might and main, thirty
or forty times, till some of them worked them-
selves into a sort of drunkenness or madness ; they
were then violently agitated, and leaped up and
down in all manner of postures, frequently for
hours together." There were sometimes thou-
sands at a single meeting of the Jumpers, shouting
out their excitement and ready to leap for joy.^
Wesley has also described instances of tremendous
emotional outburst at Methodist meetings which
he addressed. "Some were torn with a kind of
convulsive motion in every part of their bodies,
and that so violently that often four or five per-
sons could not hold one of them. I have seen
many hysterical or epileptic fits," he wrote, "but
none of them were like these in many respects."

Among the dervishes ® likewise the dance is ac-

224 BODILY CHANGES ■

companied by intense excitement and apparently
tireless movements. "The cries of 'Ya Allah !' are
increased doubly, as also those of 'Ya Hoo !' with
frightful bowlings shrieked by the dervishes to-
gether in the dance." . . . "There was no reg-
ularity in their dancing, but each seemed to be per-
forming the antics of a madman ; now moving his
body up and down; the next moment turning
round, then using odd gesticulations with his arms,
next jumping, and sometimes screaming." . , >
"At the moment when they would seem to stop
from sheer exhaustion the sheikh makes a point
of exciting them to new efforts by walking through
their midst, making also himself most violent
movements. He is next replaced by two elders,
who double the quickness of the step and the agita-
tion of the body ; they even straighten themselves
up from time to time, and excite the envy or emu-
lation of others in their astonishing efforts to con-
tinue the dance until their strength is entirely
exhausted." Such is the frenzy thus developed
that the performers may be subjected to severe
pain, yet only show signs of elation.

In all these dances the two most marked features
are the intense excitement of those who engage in
them and the very remarkable physical endurance
which they manifest. Although there is no direct
evidence, such as was obtained in examining the
football players, that bodily changes favorable to

ENEEGIZING INFLUENCE 225

great neuro-nmscular exertion are developed in
these furies of fanaticism, it is highly probahle
that they are so developed, and that the feats of
fortitude which are performed are to a large ex-
tent explicable on the basis of a "tapping of the
reservoirs of power" through the emotional ex-
citement.

The Fierce Emotions and Struggles of Battle

Throughout the discussion of the probable sig-
nificance of the bodily changes in pain and great
emotion, the value of these changes in the strug-
gles of conflict or escape was emphasized. In hu-
man beings as well as in lower animals the wildest
passions are aroused when the necessities of com-
bat become urgent. One needs only to glance at
the history of warfare to observe that when the
primitive Amotions of anger and hatred are per-
mitted full sway, men who have been considerate
and thoughtful of their fellows and their fellows'
rights suddenly may turn into infuriated savages,
slaughtering innocent women and children, muti-
lating the wounded, burning, ravaging, and looting,
with all the wild fervor of demons. It is in such
excesses of emotional turbulence that the most
astonishing instances of prolonged exertion and
incredible endurance are to be found.

Probably the fiercest struggles between men
that are recorded are those which occurred when

226 BODILY CHANGES

the wager of battle was a means of determining
innocence or guilty^In the corners of the plot se-
lected for the combat a bier was prepared for each
participant, as a symbol that the struggle was for
life or death. Each was attended by his relatives
and followers, and by his father confessor.^"
After each had prayed to God for help in the com-
ing combat, the weapons were selected, the sacra-
ment was administered, and the battle was begun.
The principals fought to the end with continuous
and brutal ferocity, resembling the desperate en-
counters of wild beasts. A fairly illustrative ex-
ample is furnished in an incident which followed
the assassination of Charles the Good of Flanders
in 1127. One of the accomplices, a knight named
Guy, was challenged for complicity by another
named Herman. Both were renowned warriors.
Herman was speedily unhorsed by Guy, who with
his lance frustrated all Herman's attempts to re-
mount. Then Herman disabled Guy's horse, and
the combat was renewed on foot with swords.
Equally skilful in fence, they continued the strug-
gle till fatigue compelled them to drop sword and
shield, whereupon they wrestled for the mastery.
Guy threw his antagonist, fell on him, and beat
him in the face with his gauntlets till he seemed to
be motionless ; but Herman had quietly slipped his
hand below the other's coat of mail and, grasping
the testicles, with a mighty effort wrenched thexn

ENERGIZING INFLUENCE 227

away. Immediately Guy fell over and expired.^*
In such terrific fights as these, conducted in the
extremes of rage and hate, the mechanisms for
reenforcing the parts of the body which are of
primary importance in the struggle are brought
fully into action and are of utmost value in secur-
ing victory.^

The Stimulating Influence op Witnesses and op Music

It is noteworthy that in all the instances thus
far cited — in the great games, in dancing, and in
fighting — two factors are present that are well
known to have an augmenting effect both in the
full development of emotions and in the perform-
ance of unusual m,uscular labors. One of these is
the crowd of witnesses or participants, who con-
tribute the "mob spirit" that tends to carry the
actions of the individual far beyond the limits set
by any personal considerations or prudencies.
The other is the influence of music. As Darwin
long ago indicated, music has a wonderful power
of recalling in a vague and indefinite manner
strong emotions which have been felt by our an-
cestors in long-past ages. Especially is this true
of martial music. For the grim purposes of war
the reed and the lute are grotesquely ill-suited ; to
rouse men to action strident brass and the jarring
instruments of percussion are used in full force.
The influence of martial music on some persons

228 BODILY CHANGES

is so profound as to cause the muscles to tremble
and tears to come to the eyes — ^both indications of
the deep stirring of emotional responses in the
body. And when deeds of fortitude and fierce ex-
ertion are to be performed the effectiveness of
such music in rousing the aggressive emotions has
long been recognized. The Romans charged their
foes amid the blasts of trumpets and horns. The
ancient Germans rushed to battle, their forces
spurred by the sounds of drums, flutes, cymbals
and clarions. There is a tradition that the Hunga-
rian troops are the worst in Europe, until their
bands begin to play — then they. are the best! The
late General Linevitch is quoted as saying : "Music
is one of the most vital ammunitions of the Eussian
army. Without music a Russian soldier would be
dull, cowardly, brutal and inefficient. From music
he absorbs a magic power of endurance, and for-
gets the sufferings and mortality. It is a divine
dynamite." And Napoleon is said to have testified
that the weird and barbaric tunes of the Cossack
regiments infuriated them to such rage that they
wiped out the cream of his army.^^ A careful
consideration of the use of martial music in war-
fare would perhaps bring further interesting evi-
dence that its function is to reenforce the bodily
changes that attend the belligerent emotions.

Only a few instances of the combination of ex-
treme pain, rage, terror or excitement, and trei-

ENERGIZING INFLUENCE 229

mendous muscular power have been given in the
preceding pages. Doubtless in numerous other
conditions these two groups of phenomena occur
together. In the lives of firemen and the police, in
the experiences of escaping prisoners, of ship-
wrecked sailors, in the struggles between pioneers
and their savage enemies, in accounts of forced
marches or retreats, search would reveal many ex-
amples of such bodily disturbances as have been
described in earlier chapters as augmenting the
effectiveness of muscular efforts, and such exhibi-
tions of power or endurance as are evidently far
beyond the ordinary. There is every reason for
believing that, were the conditions favorable to ex-
perimental testing, it would be possible to demon-
strate and perhaps to measure the addition to the
dynamics of bodily action that appears as the ac-
companiment of violent emotional disturbance.

The Feeling of Power

In this connection it is highly significant that in
times of strong excitement there is not infrequent
testimony to a sense of overwhelming power that
sweeps in like a sudden tide and lifts the person
to a new high level of ability. A friend of mine,
whose nature is somewhat choleric, has told me
that when he is seized with anger, he is also pos-
sessed by an intense conviction that he could crush
and utterly destroy the object of his hostility. And

230 BODILY CHANGES

I have heard a football player confess that just
before the final game such an access of strength
seemed to come to him that he felt able, on the
signal, to crouch and with a jump go crashing
through any ordinary door. There is intense sat-
isfaction in these moments of supreme elation,
when the body is at its acme of accomplishment.
And it is altogether probable that the critical dan-
gers of adventure have a fascination because fear
is thrilling, and extrication from a predicament, by
calling forth all the bodily resources and setting
them to meet the challenge of the difficulty, yields
many of the joys of conquest. For these reasons
vigorous men go forth to seek dangers and to run
large chances of serious injury. "Danger makes
us more alive. We so love to strive that we come
to love the fear that gives us strength for conflict.
Fear is not only something to be escaped from to
a place or state of safety, but welcomed as an ar-
senal of augmented strength."^^ And thus in
the hazardous sports, in mountain climbing, in the
hunting of big game, and in the tremendous ad-
venture of war, risks and excitement and the sense
of power surge up together, setting free unsus-
pected energies, and bringing vividly to conscious-
ness memorable fresh revelations of the possibili-
ties of achievement.

ENERGIZING INFLUENCE 231

REFEEENCES

^ Sherrington : The Integrative Action of the Nervous
System, New York, 1906, p. 265.

^ Darwin : The Expression of Emotions in Man and Ani-
mals, New York, 1905, p. 79.

^ McDougall : Introduction to Social Psychology, London,
1908, p. 50.

* James : The Energies of Men, p. 227, in Memories and
Studies, New York, 1911.

''Mooney: The Ghost -Dance Religion, United States
Bureau of Ethnology, 1892-3, p. 924.

^Schaff: Religious Encyclopedia, New York, 1908, iii,
p. 346.

^Southey: Life of Charles Wesley, New York, 1820, ii,
p. 164.

® Southey : Loc. cU., i, p. 240.

" Brown : The Dervishes, London, 1868, pp. 218-222, 260.

^^ Majer : Geschichte der Ordalien, Jena, 1796, pp. 258-
261.

11 Lea : Superstition and Force, Philadelphia, 1892, p. 178.

i^Narodny: Musical America, 1914, xx. No. 14.

i^Hall: American Journal of Psychology, 1914, xxv, p.
154.

CHAPTER XIII

THE NATURE OF HUNGER

On the same plane with pain and the dominant
emotions of fear and anger, as agencies which de-
termine the action of organisms, is the sensation
of hunger. It is a sensation so peremptory, so dis-
agreeable, so tormenting, that men have commit-
ted crimes in order to assuage it. It has led to
cannibalism, even among the civilized. It has re-
sulted in suicide. And it has defeated armies —
for the aggressive spirit becomes detached from
larger loyalties and turns personal and selfish as
hunger pangs increase in vigor and insistence.

In 1905, while observing in myself the rhythmic
sounds produced by the activities of the alimentary
tract, I had occasion to note that the sensation
of hunger was not constant but recurrent, and that
the moment of its disappearance was often associ-
ated with a rather loud gurgling sound as heard
through the stethoscope. This and other evidence,
indicative of a source of the hunger sensations in

232

THE NATUKE OF HUNGEE 233

the contractions of the digestive canal, I reported
in 1911.^ That same year, with the help of one
of my students, A. L. Washburn, I obtained final
proof for this inference.

Appetite and Hunger

The sensations of appetite and hunger are so
complex and so intimately interrelated that any
discussion of either sensation is sure to go astray
unless at the start there is clear understanding of
the meanings of the terms. The view has been
propounded that appetite is the first degree of
hunger, the mild and pleasant stage, agreeable in
character; and that hunger itself is a more ad-
vanced condition, disagreeable and even painful —
the unpleasant result of not satisfying the appe-
tite.^ On this basis appetite and hunger would
differ only quantitatively. Another view, which
seems more justifiable, is that the two experiences
are fundamentally different.

Careful observation indicates that appetite is re-
lated to previous sensations of taste and smell of
food. Delightful or disgusting ta^stes^and odors,
associated with this or that edible substance, de-
termine the appetite. It has, therefore, important
psychic elements in its composition. Thus, by tak-
ing thought, we can anticipate the odor of a de-
licious beefsteak or the taste of peaches and cream,
and in that- imagination we can find pleasure. In

234 BODILY CHANGES

the realization, direct effects in the senses of taste
and smell give still further delight. As already
noted in the first chapter, observations on experi-
mental animals and on human beings have shown
that the pleasures of both anticipation and realiza-
tion, by stimulating the flow of saliva and gastric
juice, play a highly significant role in the initiation
of digestive processes.

Among prosperous people, supplied with abun-
dance of food, the appetite seems sufficient to en-
sure for bodily needs a proper supply of nutri-
ment. We eat because dinner is announced, be-
cause by eating we avoid unpleasant consequences,
and because food is placed before us in delectable
form and with tempting tastes and odors. Under
less easy circumstances, however, the body needs
are supplied through the much stronger and more
insistent demands of hunger.

The sensation of hunger is difficult to describe,
but almost everyone from childhood has felt at
times that dull ache or gnawing pain referred to
the lower mid-chest region and the epigastrium,
which may take imperious control of human ac-
tions. As Sternberg has pointed out, hunger may
be sufficiently insistent to force the taking of food
which is so distasteful that it not only fails to
rouse appetite, but may even produce nausea. The
hungry being gulps his food with a rush. The
pleasures of appetite are not for him — he wants

THE. NATURE OF HUNGEE 235

quantity rather than quality, and he wants it at
once.

Hunger and appetite are, therefore, widely dif-
ferent — in physiological basis, in localization and
in psychic elements. Hunger may be satisfied
while the appetite still calls. Who is still hungry
when the tempting dessert is served, and yet are
there any who refuse it, on the plea that they no
longer need it? On the other hand, appetite may
be ia abeyance while hunger is goading.^ What
ravenous boy is critical of his food? Do we not
all know that "hunger is the best sauce" ? Although
the two sensations may thus exist separately, they
nevertheless have the same function of leading to
the intake of food, and they usually appear to-
gether. Indeed, the cooperation of hunger and ap-
petite is probably the reason for their being so
frequently confused.

The Sensation of Hunger

Hunger may be described as having a central
core and certain more or less variable accessories.
The peculiar dull ache of hungriness, referred to
the epigastrium, is usually the organism's first
strong demand for food ; and when the initial or-
der is not obeyed, the sensation is likely to grow
into a highly uncomfortable pang or gnawing, less
definitely localized as it becomes more intense.
This may be regarded as the essential feature of

236 BODILY CHANGES

hunger. Besides the dull ache, however, lassitude
and drowsiness may appear, or faintness, or vio-
lent headache, or irritability and restlessness such
that continuous effort in ordinary affairs becomes
increasingly difficult. That these states differ
much with individuals — ^headache in one and faint-
ness in another, for example — indicates that they
do not constitute the central fact of hunger, but
are more or less inconstant accompaniments. The
"feeling of emptiness," which has been mentioned
as an important element of the experience,* is
an inference rather than a distinct datum of con-
sciousness, and can likewise be eliminated from
further consideration. The dull pressing sensa-
tion isjfift, therefore, as the constant character-
istic, the central fact, to be examined in detail.

Hunger can evidently be regarded from the
psychological point of view, and discussed solely
on the basis of introspection ; or it can be studied
with reference to its antecedents and to the physi-
ological conditions which accompany it — a consid-
eration which requires the use of both objective
methods and subjective observation. This psycho-
physiological treatment of the subject will be de-
ferred till the last. Certain theories which have
been advanced with regard to hunger, and which
have been given more or less credit, must first be
examined.

Two main theories have been advocated. The

THE NATURE OF HUNGEE 237

first is supported by contentions that hunger is a
general sensation, arising at no special region of
the body, but having a local reference. This the-
ory has been more widely credited by physiologists
and psychologists than the other. The other is
supported by evidence that hunger has a local
source and_ therefore a local reference. In the
course of our examination of these views we shall
have opportunity to consider some pertinent new
observations.

The Theory that Hdnger is a General Sensation

The conception that hunger arises from a gen-
eral condition of the body rests in turn on the no-
tion that, as the body uses up material, the blood
becomes impoverished. Schiff ^ advocated this
notion, and suggested that poverty of the blood in
food substance affects the tissues in such manner
that they demand a new supplyj The nerve cells
of the brain share in this general shortage of pro-
visions, and because of internal changes, give rise
to the sensation. Thus is hunger explained as an
experience dependent on the body as a whole.

Three classes of evidence are cited in support
of this view:

1. "Hunger increases as time passes" — a partial
statement. The development of hunger as time
passes is a common observation which quite ac-
cords with the assumption that the condition of the

238 BODILY CHANGES

body and the state of the blood are becoming con-
stantly worse, so long as the need, once estab-
lished, is not satisfied.

While it is true that with the lapse of time hun-
ger increases as the supply of body nutriment de-
creases, this concomitance is not proof that the
sensation arises directly from a serious encroach-
ment on the store of food materials. If this argu-
ment were valid we should expect hunger to become
more and more distressing until death follows
from starvation. There is abundant evidence that
the sensation is not thus intensified; on the con-
trary, during continued fasting hunger, at least in
some persons, wholly disappears after the first few
days. Luciani,*' who carefully recorded the ex-
perience of the faster Succi, states that after a cer-
tain time the hunger feelings vanish and do not
return. And he tells of two dogs that showed no
signs of hunger after the third or fourth day of
fasting; thereafter they remained quite passive
in the presence of food. Tigerstedt,'' who also has
studied the metabolism of starvation, declares that
although the desire to eat is very great during the
first day of the ordeal, the unpleasant sensations
disappear early, and that at the end of the fast the
subject may have to force himself to take nourish-
ment. The subject, "J, A.," studied by Tigerstedt
and his co-workers,^ reported that after the fourth
day of fasting, he had no disagreeable feelings.

THE NATUEE OF HUNGEE 239

Carrington,^ after examinmg many persons
who, to better their health, abstained from eating
for different periods, records that "habit-hunger"
usually lasts only two or three days and, if plenty
of water is drunk, does not last longer than three
days. Viterbi,^" a Corsican lawyer condemned
to death for political causes, determined to escape
execution by depriving his body of food and drink.
During the eighteen days that he lived he kept
careful notes. On the third day the sensation of
hunger departed, and although thereafter thirst
came and went, hunger never returned. Still fur-
ther evidence of the same character could be cited,
but enough has already been given to show that
after the first fe w days o f fasting the hunger feel-,
ings may wholly cease. On the theory that hunger
is a manifestation of bodily need, are we to sup-
pose that, in the course of starvation, the body is '
mysteriously not in need after the third day, and;
that therefore the sensation of hunger disappears?
The absurdity of such a view is obvious.

2. "Hunger may be felt though the stomach be
full" — a selected alternative. Instances of duo-
denal fistula in man have been carefully studied,
which have shown that a modified sensation of
hunger may be felt when the stomach is full. A
famous case described by Busch ^^ has been re-
peatedly used as evidence. His patient, who lost
nutriment through a duodenal fistula, was hungry

240 BODILY CHANGES

soon after eating, and felt satisfied only wlien the
chyme was restored to the intestine through the
distal fistulous opening. As food is ahsorhed
mainly through the intestinal wall, the inference
is direct that the general bodily state, and not the
local conditions of the alimentary canal, must ac-
count for the patient's feelings.

A full consideration of the evidence from cases
of duodenal fistula cannot so effectively be pre-
sented now as later. That in Busch's case hunger
disappeared while food was being taken is, as we
shall see, quite significant. It may be that the
restoration of chyme to the intestine quieted
hunger, not because nutriment was thus intro-
Iduced into the body, but because the presence of
i material altered the nature of gastro-intestinal
activity. The basis for this suggestion will be
given in due course.

3. "Animals may eat eagerly after section of
their vagus and splanchnic nerves" — a fallacious
argument. The third support for the view that
hunger has a general origin in the body is derived
from observations on experimental animals. By
severance of the vagus and splanchnic nerves, the
lower esophagus, the stomach and the small in-
testine can be wholly separated from the central
nervous system. Animals thus operated upon
nevertheless eat food placed before them, and may
indeed manifest some eagerness for it.*^ How

THE NATUEE OF HUNGEE 241

is this behavior to be accounted for — when the
possibility of local stimulation has been eliminated
— ^^save by assuming a central origin of the impulse
to eat?

The fallacy of this evidence, though repeatedly
overlooked, is easily shown. We have already seen
that appetite as well as hunger may lead to the
taking of food. Indeed, the animal with all gas-
tro-intestinal nerves cut may have the same in-
centive to eat Jhat a well-fed man may have, who
delights in the pleasurable taste and smell of food
and knows nothing of hunger pangs. Even when
the nerves of taste are cut, as they were in
Longet's experiments,^^ sensations of smell are
still possible, as well as agreeable associations
which can be roused by sight. More than fifty
years ago Ludwig ^* pointed out that, even if
all the nerves were severed, psychic reasons could
be given for the taking of food, and yet because
animals eat after one or another set of nerves is
eliminated, the conclusion has been drawn by vari-
ous writers that the nerves in question are thereby
proved to be not concerned in the sensation of
hunger. Evidently, since hunger is not required!
for eating, the act of eating is no testimony what-l
ever that the animal is hungry, and, after tha
nerves have been severed, is no proof that hunger'
is of central origin.

242 BODILY CHANGES

Weakness of the Assumptions Underlying the Theory
THAT Hunger is a General Sensation

The evidence tlras far examined has been shown
to afford only shal^y support for the theory that
hunger is a general sensation. The theory, fur-
thermore, is weak in its fundamental assumptions.
There is no clear indication, for example, that the
blood undergoes or has undergone any marked
change, chemical or physical, when the first stages
of hunger appear. There is no evidence of any
direct chemical stimulation of the gray matter of
the cerebral cortex. Indeed, attempts to excite the
gray matter artificially by chemical agents have
been without results ;^^ and even electrical stim-
ulation, which is effective, must, in order to
produce movements, be so powerful that the move-
ments have been attributed to excitation of under-
lying white matter rather than cells in the gray.
This insensitivity of cortical cells to direct stimu-
lation is not at all favorable to the notion that they
are sentinels set to warn against too great diminu-
tion of bodily supplies.

Body Need May Exist Without Hunger

Still further evidence opposed to the theory that
hunger results directly from the using up of or-
ganic stores is found in patients suffering from
I fever . Metabolism in fever patients is augmented,
I body substance is destroyed to such a degree that

THE NATURE OF HUNGER 243

the weight of the patient may be greatly reduced,
and yet the sensation of hunger under these condi-
tions of increased need is wholly lacking.

Again, if a person is hungry and takes food,
the sensation is suppressed soon afterwards, long
before any considerable amount of nutriment
cjould be _digestfid-^ and- absorbed, and therefore
long before the blood and the general bodily condi-
tkin, if previously altered, could be restored to
norma l.

Furthermore, persons exposed to privation have
testified that hunger can be temporarily sup-
pressed by swallowing indigestible materials. Cer-
tainly scraps of leather and bits of moss, not to
mention clay eaten by the Otomacs, wou ld not ma -
terially compensate for large organic losses. In
rebuttal to this argument the comment has been
made that central states as a rule can be readily
overwhelmed by peripheral stimulation, and just
as sleep, for example, can be abolished by bathing
the temples, so hunger can be abolished by irritat-
ing the gastric walls.^^ This comment is beside
the point, for it meets the issue by merely assum-
ing as true the condition under discussion. The.
absence of hunger during the ravages of fever, and
its quick abolition after food or even indigestible
stuff is swallowed, still further weakens the argu-
ment, therefore, that the sensation arises directly
from lack of nutriment in the body.

244 BODILY CHANGES

The Theory that Hunger is of General Origin Does Not

Explain the Quick Onset and the Periodioittt

OP THE Sensation

Many persons have noted that hunger has a
sharp onset. A person may be tramping in the
woods or working in the fields, where fixed atten-
tion is not demanded, and without premonition
raay feel the abrupt arrival of the characteristic
ache. The expression "grub-struck" is a pic-
turesque description of this experience. If this
sudden arrival of the sensation corresponds to the
general bodily state, the change in the general bod-
ily state must occur with like suddenness or have
a critical point at which the sensation is instantly
precipitated. There is no evidence whatever that
either of these conditions occurs in the course of
metabolism.

Another peculiarity of hunger, which I have al-
ready mentioned, is its intermitteney. It may
come and go several times in the course of a few
hours. Furthermore, while the sensation is pre-
vailing, its intensity is not uniform, but marked
by ups and downs. In some instances the ups and
downs change to a periodic presence and absence
without change of rate. In my own experience the
hunger pangs came and went on one occasion as
follows :

Came Went

12— 3Y— 20 38—30

40—45 41—10

THE NATUEE OF HUNGER 245

Came

Went

41—45

42—25

43—20

43—35

44-^0

45—55

46—15

46—30

and so on, for ten minutes longer. Again in this
relation, the intermittent and periodic character
o^hunger_ would require, on the theory under ex-
amination, that the bodily supplies be intermittent-
ly and periodically insufficient. During one mo-
ment the absence of hunger would imply an
abundance of nutriment in the organism, ten sec-
onds later the presence of hunger would imply
that the stores had been suddenly reduced, ten
seconds later still the absence of hunger would
imply a sudden renewal of plenty. Such zig-zag
shifts of the general bodily state may not be im-
possible, but from all that is known of the course
of metabolism, such quick changes are highly im-^
probabl e. The periodicity of hui^ger, therefore, is
further evidence against t]ie theory that the sensa-
tion has a general basis in the body.

The Theory that Hunger is of General Origin Does Not
Explain the Local Reference

The last objection to this theory is that it does
not account for the most common feature of
hunger — ^namely, the reference of the sensation to
the region of the stomach. Schiff and others "
who have supported the theory have met this

246 BODILY CHANGES "

objection by two contentions. First they bave
pointed out that the sensation is not always re-
ferred to the stomach. Schiff interrogated igno-
■rjint soldiers regarding the local reference; sev-
eral indicated the neck or chest, twenty-three the
sternum, four were uncertain of any region, and
two only designated the stomach. In other words,
the stomach region was most rarely mentioned.

The second contention against the importance
of local reference is that such evidence is falla-
cious. An armless man may feel tinglings which
seem to arise in fingers which have long since
ceased to be a portion of his body. The fact that
he experiences such tinglings and ascribes them to
dissevered parts, does not prove that the sensa-
tion originates in those parts. And similarly the
assignment of the ache of hunger to any special
region of the body does not demonstrate that the
ache arises from that region. Such are the argu-
ments against a local origin of hunger.

Concerning these arguments we may recall, first,
Schiff's admission that the soldiers he questioned
were too few to give conclusive evidence. Further,
the testimony of most of them that hunger seemed
to originate in the chest or region of the sternum
cannot be claimed as unfavorable to a peripheral
source of the sensation. The description of feel-
ings which develop from disturbances within the
body is almost always indefinite. As Head ^^

THE NATURE OF HUNGER 247

and others have shown, conditions in a viscus
which give rise to sensation are likely not to be at-
tributed to the viscus, but to related skin areas.
Under such circumstances we do not dismiss
the testimony as worthless merely because it
may not point precisely to the source of the
trouble. On the contrary, we use such testimony
constantly as a basis for judging internal dis-
orders.

With regard to the contention that reference to
the periphery is not proof of the peripheral origin
of a sensation, we may answer that the force of
that contention depends on the amount of acces-
sory evidence which is available. Thus if we see
an object come into contact with a finger, we are
justified ia assuming that the simultaneous sensa-
tion of touch which we refer to that finger has re-
sulted from the contact, and is not a purely central
experience accidentally attributed to an outlying
member. Similarly in the case of hunger — all that
we need as support for the peripheral reference of
the sensation is proof that conditions occur there, ,
simultaneously with hunger pangs, which might
reasonably be regarded as giving rise to those
pangs.

With the requirement in mind that peripheral
conditions be adequate, let us examine the state
of the fasting stomach to see whether, indeed, con-
ditions may be present in times of hunger which

248 BODILY CHANGES

would sustain the theory that hunger has a local
outlying source.

Hunger Not Due to Emptiness of the Stomach

Among the suggestions which have been offered
to account for a peripheral origin of the sensation
is that of attributing it to emptiness of the stom-
ach. By use of the stomach tube Nicolai ^* found
that when his subjects had their first intima-
tion of hunger the stomach was quite empty.
But, in other instances, after lavage of the stomach,
the sensation did not appear for intervals vary-
ing between one and a half and three and a half
hours. During these intervals the stomach must
have been empty, and yet no sensation was experi-
enced. The same testimony was given long before
by Beaumont,^" who, from his observations on
Alexis St. Martin, declared that hunger arises some
time after the stomach is normally evacuated.
Mere emptiness of the organ, therefore, does not
explain the phenomenon.

Hunger Not Due to Hydrochloric Acid in the Empty
Stpmach

A second theory, apparently suggested by obser-
vations on cases of hyperacidity, is that the ache or
pang is due to the natural hydrochloric acid of the
stomach but secreted while the organ is empty.
Again the facts are hostile. Nicolai ^* reported

THE NATURE OF HUNGER 249

that the gastric wash-watei; from his hungry sub-
jects was neutral or only slightly acid. This
testimony confirms Beaumont's statement, and
is in complete agreement with the results of
gastric examination of fasting animals reported
by numerous experimenters. There is no secre-
tion into the empty stomach during the first days
of starvation. Furthermore, persons suffering
from absence of hydrochloric acid (achylia gas-
trica) declare that they have normal feelings of
hunger. Hydrochloric acid cannot, therefore, be
called upon to account for the sensation.

Hunger Not Due to Turgescenoe of the Gastric Mucous
Membrane

Another theory, which was first advanced by
Beaumont,^^ is that hunger arises from turges-
cence of the gastric glands. The disappearance of
the pangs as fasting continues has been accounted
for by supposing that the gastric glands share in
the general depletion of the body, and that thus the
turgescence is relieved.* This turgescence theory
has commended itself to several recent writers.
Thus Luciani^^ has accepted it, and by adding
the idea that nerves distributed to the mucosa are

* A better explanation perhaps is afforded by BoldirefE's
discovery that at the end of two or three days the stomachs
of fasting dogs begin to secrete gastric juice and continue
the secretion indefinitely. (Boldireff, Archives Biologiques
de St. Petersburg, 1905, xi, p. 98.)

250 BODILY CHANGES

specially sensitive to deprivation of food lie ac-
counts for the hunger pangs. Also Valenti ^*
declared a few years ago that the turgescence
theory of Beaumont is the only one with a sem-
blance of truth in it. The experimental work re-
ported by these two investigators, however, does
not necessarily sustain the turgescence theory.
Luciani severed the previously exposed vagi after
cocainizing them, and Valenti merely cocainized
the nerves; the fasting dogs, eager to eat a few
minutes previous to this operation, now ran about
as before, but when offered food, licked and smelled
it, but did not take it. This total neglect of the
food lasted varying periods up to two hours. The
vagus nerves seem, indeed, to convey impulses
which affect the procedure of eating, but there is
no clear evidence that those impulses arise from
distention of the gland cells. The turgescence
theory, moreover, does not explain the effect of
taking indigestible material into the stomach.
According to Pawlow, and to others who have ob-
served human beings, the_chewing and swallowing
of unappetizing stuff does not cause any secretion
of__gastric juice (see p. 8). Yet such stuff when
swallowed will cause the disappearance of hunger,
and Nicolai found that the sensation could be abol-
ished by simply introducing a stomach sound. It
is highly improbable that the turgescence of the
gastric glands can be reduced by either of these

A'

THE NATURE OF HUNGER 251

procedures. The turgescence theory, furthennore,A
does not explain the quick onset of hunger, or its
intermittent and periodic character. That the cells j
are repeatedly swollen and contracted within peri-
ods a few seconds in duration is almost inconceiv-
able. For these reasons, therefore, the theory that
hunger results from turgescence of the gastric
mucosa can reasonably be rejected.

Hunger the Result of Contractions

There remain to be considered, as a possible
cause of hunger-pangs, contractions of the stomach
and other parts of th e alimenta ry canal. This sug-
\ gestion is not n ew. "^ S i xty-nine Ik ears ago Weber ^^
^^ declared his belief that "strong contraction of
the muscle fibres of the wholly empty stomach,
whereby its cavity disappears, makes a part of the
sensation which we call hunger." Vierordt ^^ drew
the same inference twenty-five years later (in
1871), and since then Ewald, Knapp, and Hertz
have declared their adherence to this view. These
writers have not brought forward any direct evi-
dence for their conclusion, though Hertz has cited
Boldireff's observations on fasting dogs as prob-
ably accounting for what he terms "the gastric
constituent of the sensation."

The Empty Stomach and Intestine Contract

The argument commonly used against the gas-
tric contraction theory is that the ^iqmach is not

252 BODILY CHANGES

energetically active when empty. Thus Schiff ^^
stated, "The movements of the empty stomach
are rare and much less energetic than during diges-
tion." Luciani ^® expressed his disbelief by as-
serting that gastric movements are much more ac-
tive during gastric digestion than at other times,
and cease almost entirely when the stomach has
discharged its contents. And Valenti ^® stated
(1910), "We know very well that gastric move-
ments are exaggerated while digestion is proceed-
ing in the stomach, but w;hen the organ is empty
they are more rare and much less pronounced,"
and, therefore, they cannot account for hunger.

Evidence opposed to these suppositions has been
in existence for many years. In 1899 Bettmann *"
called attention to the contracted condition of
the stomach after several days' fast. In 1902
Wolff ^^ reported that after forty-eight hours
without food the stomach of the cat may be so small
as to look like a slightly enlarged duodenum. In a
similar circumstance I have noticed the same ex-
traordinary smallness of the organ, especially in
the pyloric half. The anatomist His ^^ also re-
corded his observation of the phenomenon. In 1905
Boldireff ^^ demonstrated that the whole gastro-
intestinal tract has a periodic activity while not di-
g^esting. Each period of activity lasts from twenty
to thirty minutes, and is characterized in the stom-
ach by rhythmic contractions ten to twenty in num-

THE NATURE OF HUNGEE 253

ber. These contractions, Boldireff reports, may be/
stronger_than during digestion, and his published
records clearly support this stateraent. The inteij-
vals of repose between periodic recurrences of the
contractions lasted from one and a half to two and
a half hours. Especially noteworthy is Boldireff's
observation that if fasting is continued for two or
three days, the groups of contractions appear at
gradually longer intervals and last for gradually
shorter periods, and thereupon, as the gastric
glands begin continuous secretion, all movements
cease.

Observations Suggesting that Contractions Oausk
Hunger

The research, previously mentioned, on the
rhythmic sounds produced by the digestive pro-
cess, I was engaged in when Boldireff' s paper was
published. That contractions of the alimentary
canal on a gaseous content might explain the hun-
ger pangs which I had noticed seemed probable at
that time, especially in the light of Boldireff's ob-
servations. Indeed, Boldireff ^* himself had con-
sidered hunger in relation to the activities he
described, but solely with the idea that hunger
might provoke them ; and since the activities dwin-
dled in force and frequency as time passed, where-
as, in his belief, they should have become more pro-
nounced, he abandoned the notion of any relation

254 BODILY CHANGES

between tlie phenomena. Did not Boldireff misin-
terpret his own observations? When he was con-
/ sidering whether hunger might cause the contrac-
tions, did he not overlook the possibility that the
contractions might cause hunger? A number of
experiences have led to the conviction that Boldi-
reff did, indeed, fail to perceive part of the signifi-
cance of his results. For example, I have noticed
the disappearance of a hunger pang as gas was
heard gurgling upward through the cardia. That
the gas was rising rather than being forced down-
ward was proved by its regurgitation immediately
after the sound was heard. In all probability the
pressure that forced the gas from the stomach was
the cause of the preceding sensation of hunger.
Again the sensation can be momentarily abolished
a few seconds after swallowing a small accumula-
tion of saliva or a teaspoonful of water. If the
stomach is in strong contraction in hunger, this re-
sult can be accounted for, in accordance with the
observations of Lieb and myself,^^ as due to the
inhibition of the contraction by swallowing. Thus
also could be explained the prompt vanishing of
the ache soon after we begin to eat, forjepeated
swallowing results in continued in hibitio n.* Fur-
thermore, Ducceschi's discovery ^® that hydro -

* The absence of hunger in Busch's patient while food waa
being eaten (see p. 239) can also be accounted for in this
manner.

THE NATURE OF HUNGEE 255

chloric acid d iminishes the tonus of the pyloric por-
tion of the stomach .may have its application here ;
the acid would be secreted as food is taken and
would then cause relaxation of the very region
which is most strongly contracted.

The Concomitance of Contractions ajstd Hunger in Man

Although the evidence above outlined had led
me to the conviction that hunger results from con-
tractions of the alimentary canal, direct proof was
still lacking. In order to learn whether such proof
might be secured, Washburn determined to be-
come accustomed to the presence of a rubber tube
in the esophagus.* Almost every day for several
weeks Washburn introduced as far as the stomach
a small tube, to the lower end of which was attached
a soft-rubber balloon about 8 centimeters in diam-
eter. The tube was thus carried about each time
for two or three hours. After this preliminary
experience the introduction of the tube and its
presence in the gullet and stomach were not at all
disturbing. When a record was to be taken, the
balloon, placed just within the stomach, was moder-
ately distended with air, and was connected with a
water manometer ending in a cylindrical chamber
3.5 centimeters wide. A float recorder resting on

* Nicolai (loc. cit.) reported that although the introduction
of a stomach tube at first abolished hunger in his subjects,
with repeated use the effects became insignificant.

256 BODILY CHANGES

the water in the chamber permitted registering any
contractions of the fundus of the stomach. On the
days of observation Washburn would abstain from
breakfast, or eat sparingly; and without taking
any luncheon would appear in the laboratory about
two o'clock. The recording apparatus was ar-
ranged as above described. In order to avoid any
error that might arise from artificial pressure on
the balloon, a pneumograph, fastened below the
ribs, was made to record the movements of the
abdominal wall. Uniformity of these movements
would show that no special contractions of the ab-
dominal muscles were made. Between the records
of gastric pressure and abdominal movement, time
was marked in minutes, and an electromagnetic
signal traced a line which could be altered by press-
ing a key. All these recording arrangements were
out of Washburn's sight; he sat with one hand at
the key, ready whenever the sensation of hunger
was experienced to make the current which moved
the signal.

Sometimes the observations were started before
any hunger was noted ; at other times the sensa-
tion, after running a course, gave way to a feeling
of fatigue. Under either of these circumstances
there were no contractions of the stomach. When
Washburn stated that he was hungry, however,
powerful contractions of the stomach were invari-
ably being registered. As in my own earlier expe-

THE NATUEE OF HUNGEE 257

rience, the sensations were characterized by peri-
odic recurrences with free intervals, or by peri-
odic accesses of an uninterrupted ache. The record
of Washburn's introspection of his hunger pangs'
agreed closely with the record of his gastric con-

FiGUBE 37. — One-half the original size.
The top record represents intragastric pres-
sure (the small oscillations due to respiration,
the large to contractions of the stomach) ; the
second record is time in minutes (ten min-
utes) ; the third record is W's report of hunger
pangs; the lowest record is respiration regis-
tered by means of a pneumograph about the
abdomen.

tractions. Almost invariably, however, the con-
traction nearly reached its maximum before the
record of the sensation was started (see Fig. 37). {
This fact may be regarded as evidence that the
cont raction precedes the sensation, and not vice
versa, as Boldireff considered it. The contrac-
tions were about a half -minute in duration, and

258

BODILY CHANGES

the intervals between varied from thirty to ninety
seconds, with an average of about one minute. The
augmentations of intragastric pressure in Wash-
burn ranged between eleven and thirteen in twenty
minutes ; I had previously counted in myself eleven
hunger pangs in the same time. The rate in each

Figure 38. — One-half the original size. The same conditions
as in Fig. 37. (Fifteen minutes.) There was a long wait for hunger
to disappear. After x, W. reported himself "tired but not hungry."
The record from y to z was the continuance, on a second drum, of
X toy.

of US was, therefore, approximately the same.
This rate is slightly slower than that found in
dogs by Boldireff ; the difference is perhaps corre-
lated with the slower rhythm of gastric peristalsis
in man compared with that in the dog.^''

Before hunger was experienced by Washburn
the recording apparatus revealed no signs of gas-
tric activity. Sometimes a rather tedious period
of waiting had to be endured before contractions

THE NATUEE OF HUNGER 259

dccurred. And after they began they continued
for a while, then ceased (see Fig. 38) . The feeling
of hunger, which was reported while the contrac-
tions were recurring, disappeared as the waves
stopped. The inability of the subject to controR .
the contractions eliminated the possibility of their j ' "^ '^'^^
being artifacts, perhaps induced by sugges tion.!
The close concomitance of the contractions with
hunger pangs, therefore, clearly indicates. that they
are the real source of those pangs.

Boldireff's studies proved that when the empty
stomach is manifesting periodic contractions, the
intestines also are active. Conceivably all parts
of the alimentary canal composed of smooth mus-
cle share in these movements. The lower esopha-
gus in man is provided with smooth muscle. It
was possible to determine whether this region in
"Washburn was active during hunger.

To the esophageal tube a thin-rubber finger-cot
(2 centimeters in length) was attached and lowered
into the stomach. The little rubber bag was dis-
tended with air, and the tube, pinched to keep the
bag inflated, was gently withdrawn until resistance
was felt. The air was now released from the bag'
and the tube farther withdrawn about 3 centi-
meters. The bag was again distended with air at
a manometric pressure of 10 centimeters of water.
Inspiration now caused the writing lever, which:
recorded the pressure changes, to rise; and a:

( ( <

260

BODILY CHANGES

slightly farther withdrawal of the tube changed
the rise, on inspiration, to a fall. The former posi-
tion of the tube, therefore, was above the gastric
cavity and below the diaphragm. In this position

Figure 39. — One-half the original size.
The top record represents compression of
thin rubber bag in the lower esophagus.
The pressure in the bag varied between 9
and 13 centimeters of water. The cylin-
der of the recorder was of smaller diameter
than that used in the gastric records. The
esophageal contractions compressed the
bag so completely that, at the summits of
the large oscillations, the respirations were
not registered. When the oscillations
dropped to the time line, the bag was about
half inflated. The middle line registers
time in minutes (ten minutes). The bot-
tom record is W's report of hunger pangs.

the bag, attached to a float recorder (with chamber
2.3 centimeters in diameter), registered the peri-
odic oscillations shown in Fig. 39. Though indi-
vidually more prolonged than those of the stomach,
these contractions, it will be noted, occur at about
the same rate.

THE NATURE OF HUNGER 261

This study of hunger, reported by Washburn
and myself in 1912, has since been taken up by
Carlson of Chicago, and in observations on a man
with a permanent gastric fistula, as well as on him-
self and his collaborators, he has fully confirmed
our evidence as to the relation between contrac-
tions of the alimentary canal and the hunger sensa-
tion. In a series of nearly a score of interesting
papers, Carlson and his students ^^ have greatly
amplified our knowledge of the physiology of the
"empty" stomach. Not only are there the contrac-
tions observed by Washburn and myself, but at
times these may fuse into a continuous cramp of
the gastric muscle. The characteristic contrac-
tions, furthermorej, continue after the vagus^ nerve
supply to the stomach has been destroyed, and,
therefore, are not dependent on the reception of
impulses by way^of^the cranial autonomic fibres.
Recently Luckhardt and Carlson have brought for-
ward evidence that the blood of a fasting animal -,
if injected into the vein of a normal animal is j
capable of inducing in the latter the condition of !
cramp or tetanus in the gastric muscle mentioned
above — an effect which does not occur when the j
blood of a well-fed animal is injected. It seems i
possible that a substance exists in the blood which
acts to excite the gastric hunger mechanism. But
this point will require further investigation.

With these demonstrations that contractions are

262 BODILY CHANGES

the immediate cause of hunger, most of the diffi-
culties confronting other explanations are readily
obviated. Thus the sudden onset of hunger and
its peculiar periodicity — phenomena which no
other explanation of hunger can account for — are
at once explained.

In fever, when bodily material is being most
rapidly used, hunger is absent. Its absence is
understood from an observation made by F. T.
Murphy and myself,*"* that infection, with sys-
temic involvement, is accompanied by a total
cessation of ^11 movements of the alimentary canal.
Boldireff observed that when his dogs were fa-
tigued the rhythmic contractions failed to appear.
Being "too tired to eat" is thereby given a rational
explanation.

A pathological form of the sensation — the inor-
dinate hunger (bulimia) of certain neurotics — is
in accordance with the well-known disturbances
of the tonic innervation of the alimentary canal
in such individuals.

Since the lower end of the esophagus, as well
as the stomach, contracts periodically in hunger,
the reference of the sensation to the sternum by
the ignorant persons questioned by Schiff was
wholly natural. The activity of the lower esopha-
gus also explains why, after the stomach has been
removed, or in some cases when the stomach is
distended with food, hunger can still be experi-

THE NATURE OF HUNGER 263

enced. Conceivably the intestines also originate
vague sensations by tbeir contractions. Indeed,
the final banishment of the modified hunger sen-
sation in the patient with duodenal fistula, de-
scribed by Busch, may have been due to the les-
sened activity of the intestines when chyme was
injected into them.

The observations recorded in this paper have,
as already noted, numerous points of similarity to
Boldireff's observations '"' on the periodic activ-
ity of the alimentary canal in fasting dogs. Each
period of activity, he found, comprised not only
wide-spread contractions of the digestive canal, but
also the pouring out of bile, and of pancreatic and
intestinal juices rich in ferments. G astric juice
was not secreted at these times; when it was se-
creted and reac hed thejntestine, the periodic activ-
ity ceased . What is the significance of this exten-
sive disturbance 1 I have elsewhere presented evi-
dence *^ that gastric peristalsis is dependent on
the stretching of gastric muscle when tonically con-
tracted. The evidence that the stomach is in fact
strongly contracted in hunger — i. e., in a state of
high tonus — has been presented above.* Thus

* The "empty" stomach and esophagus contain gas (see
Hertz : Quarterly Journal of Medicine, 1910, iii, p. 3Y8 ;
Mikulicz : Mittheilungen aus den Grenzgebieten der Medi-
cin und Chirurgie, 1903, xii, p. 596). They would naturally
manifest rhythmic contractions on shortening tonically on
their content.

264 BODILY CHANGES

the very condition which, causes hunger and leads
to the taking of food is the condition, when the
swallowed food stretches the shortened muscles,
for immediate starting of gastric peristalsis. In
this connection the observations of Haudek and
Stigler *^ are probably significant. They found
that the stomach discharges its contents more rap-
idly if food is eaten in hunger than if not so eaten.
Hunger, in other words, is normally the signal that
the stomach is contracted for action; the unpleas-
antness of hunger leads to eating; eating starts
gastric digestion, and abolishes the sensation.
Meanwhile the pancreatic and intestinal juices, as
well as bile, have been prepared in the duodenum
to receive the oncoming chyme. The periodic ac-
tivity of the alimentary canal in fasting, therefore,
is not solely the source of hunger pangs, but is at
the same time an exhibition in the digestive organs
of readiness for prompt attack on the food swal-
lowed by the hungry animal.

EEFEEENCES

* Cannon : The Mechanical Factors of Digestion, London
and New York, 1911, p. 204.

*Bardier: Richet's Dictionnaire de Physiologie, article
Faim, 1904, vi, p. 1. See, also, Howell : Text-book of Physi-
ology, fourth edition, Philadelphia and London, 1911, p. 285.

* See Sternberg : Zentralblatt f iir Physiologie, 1909,
xxii, p. 653. Similar views were expressed by Bayle in a
thesis presented to the Faculty of Medicine in Paris in 1816.

♦See Hertz: The Sensibility of the Alimentary Canal,
London, 1911, p. 38.

THE NATURE OF HUNGER 265

•SchifE: Physiologie de la Digestion, Florence and Turin,
1867, p. 40.

" Luciani : Das Hungern, Hamburg and Leipzig, 1890,
p. 113.

' Tigerstedt : Nagel's Handbuch der Physiologie, Berlin,
1909, i, p. 376.

^ Johanson, Landergren, Sonden and Tigerstedt : Skandi-
navisches Arehiv fiir Physiologie, 1897, vii, p. 33.

° Oarrington : Vitality, Pasting and Nutrition, New
York, 1908, p. 555.

^° Viterbi, quoted by Bardier : Loc. cit., p. 7.

^^ Busch : Arehiv fiir pathologische Anatomie und Physi-
ologie und fiir klinische Medicin, 1858, xiv, p. 147.

^^ See Schiff : Loc. cit., p. 37; also Ducceschi; Archivio di
Fisiologia, 1910, viii, p. 579.

13 Longet : Traite de Physiologie, Paris, 1868, i, p. 23.

1* Ludwig : Lehrbuch der Physiologie des Menschen, Leip-
zig and Heidelberg, 1858, ii, p. 584.

15 Maxwell : Journal of Biological Chemistry, 1906-7, ii,
p. 194.

"See Schiff: Loc. cit., p. 49.

1' See Schiff: Loc. cit., p. 31; Bardier; Loc. cit., p. 16.

"Head: Brain, 1893, xvi, p. 1; 1901, xxiv, p. 345.

1" Nicolai : Ueber die Entstehung des Hungergef iihls, In-
augural Dissertation, Berlin, 1892, p. 17.

2" Beaumont: The Physiology of Digestion, second edi-
tion, Burlington, 1847, p. 51.

21 Nicolai : Loc. cit., p. 15.

22 Beaumont: Loc. cit., p. 55.

23 Luciani : Archivio di Fisiologia, 1906, iii, p. 54. Tiede-
mann long ago suggested that gastric nerves become increas-
ingly sensitive as fasting progresses. (Physiologie des Men-
schen, Darmstadt, 1836, iii, p. 22.)

2* Valenti : Archives Italiennes de Biologie, 1910, liii, p. 94.

'"' Weber : Wagner's Handworterbuch der Physiologie, 1846,
iii2, p. 580.

2''Vierordt: Grundriss der Physiologie, Tiibingen, 1871,
p. 433.

2' Schiff: Loc. cit., p. 33.

266 BODILY CHANGES

^^Luciani: Loc. cit., p. 542.

2" Valenti : Loc. cit., p. 95.

2» Bettmann : Philadelphia Monthly Medical Journal, 1899,
i, p. 133.

=*! Wolff : Dissertation, Giessen, 1902, p. 9.

32 His : Archiv f iir Anatomie, 1903, p. 345.

^^ Boldireff : Loc. cit., p. 1.

3^ Boldireff : Loc. cit., p. 96.

3^ See Cannon and Lieb : American Journal of Physiol-
ogy, 1911, xxix, p. 267.

^i' Ducceschi: Archivio per le Scienze Mediche, 197, xxi,
p. 154.

^'' See Cannon : American Journal of Physiology, 1903,
viii, p. xxi ; 1905, xiv, p. 344.

3* See American Journal of Physiology, 1913, 1914.

3^ Cannon and Murphy : Journal of the American Medi-
cal Association, 1907, xlix, p. 840.

*» Boldireff: Loc. cit., pp. 108-111.

^"^ Cannon : American Journal of Physiology, 1911, xxix,
p. 250.

*2 Haudek and Stigler : Archiv f iir die gesammte Physi-
ologic, 1910, cxxxiii, p. 159.

CHAPTER XIV

THE INTEKKELATIONS OF EMOTIONS

Emotions gain exp ression through discharges
along the neurones qf the autonomic nervous sys-
iem. The reader will recall that this system has
three divisions — the cranial and sacral, separated
hy the sympathetic — and that when the neurones of
the mid-division meet in any organ the neurones of
either of the end divisions, the influence of the two
sets is antagonistic. As previously stated (p. 35),
there is evidence that arrangements exist in the
central nervous system for reciprocal innervation
of these antagonistic divisions, just as there is
reciprocal innervation of antagonistic skeletal
muscles. The characteristic affective states mani-
fested in the working of these three divisions have
been described. Undoubtedly, these states have
correspondents — activities and inhibitions — in the
central neurones. The question now arises, are
the states which appear in opposed divisions also
in opposition?

267

268 BODILY CHANGES

Antagonism Between Emotions Expressed in the Sympa-
thetic AND IN the Cranial Divisions of the Autonomio
System

The cranial autonomic, as already shown, is con-
cerned with- the quiet service of building up re-
serves and fortifying the body against times of
stress. Accompanying these functions are the
relatively mild pleasures of sight and taste and
smell of food. The possibility of existence of these
gentle delights of eating and drinking and also of
their physiological consequences is instantly abol-
ished in the presence of emotions which activate
the sympathetic division. The secretion of saliva,
gastric juice, pancreatic juice and bile is stopped,
and the motions of the stomach and intestines cease
at once, both in man and, in the lower animals,
whenever pain, fear, rage, or other strong excite-
ment is present in the organism.

All these disturbances of digestion seem mere
interruptions of the "normal" course of events
unless the part they may play in adaptive reac-
tions is considered. In discussing the operations
of the sympathetic division, I pointed out that all
the bodily changes which occur in the intense emo-
tional states — such as fear and fury — occur as
results of activity in this division, and are in the
highest degree serviceable in the struggle for exist-
ence likely to be precipitated when these emotions
are aroused. From this point of view these per-

INTERRELATIONS OP EMOTIONS 269

turbations, which, so readily seize and dominate
the organs that in quiet times are commonly con-
trolled by the cranial autonomic, are bodily reac-
tions which may be of the utmost importance to life
at times of critical emergency. Thus are the body's
reserves — the stored adrenin and the accumulated
sugar — called forth for instant service ; thus is the
blood shifted to nerves and muscles that may have
to bear the brunt of struggle ; thus is the heart set
rapidly beating to speed the circulation ; and thus,
also, are the activities of the digestive organs for
the time abolished. Just as in war between nations
the arts and industries which have brought wealth
and contentment must suffer serious neglect or be
wholly set aside both by the attacker and the at-
tacked, and all the supplies and energies developed
in the period of peace must be devoted to the pres-
ent conflict; so, likewise, the functions which in
quiet times establish and support the bodily re-
serves are, in times of stress, instantly checked
or completely stopped, and these reserves lavishly
drawn upon to increase power in the attack and in
the defense or flight.*

It is, therefore, the natural antagonism between
these two processes in the body — between saving

* One who permits fears, worries and anxieties to disturb
the digestive processes when there is nothing to be done, is
evidently allowing the body to go onto what we may regard
as a "war footing," when there is no "war" to be waged, no
fighting or struggle to be engaged in.

270 BODILY CHANGES

and expenditure, between preparation and use, be-
tween anabolism and catabolism — and the corre-
lated antagonism of central innervations, that un-
derlie the antipathy between the emotional states
which normally accompany the processes. The
desire for food, the relish of eating it, all the
pleasures of the table, are naught in the presence
of anger or great anxiety. And of the two sorts
of emotional states, those which manifest them-
selves in the dominant division of the autonomic
hold the field also in consciousness.

Antagonism Between Emotions Expressed nsr the Sympa-
thetic AND IN THE SaCRAL DIVISIONS OF THE AUTONOMIC

System

The nervi erigentes are the part of the sacral
autonomic in which the peculiar excitements of
sex are expressed. As previously stated, these
nerves are opposed by branches from the sympa-
thetic division — the division which is operated
characteristically in the major emotions.

The opposition in normal individuals betweenihe
emotional states which appear in these two antag-
onistic divisions is most striking. Even in animals
as low in the scale as birds, copulation is not per-
formed "until every condition of circumstance and
sentiment is fulfilled, until time, place and partner
all are fit."^ And among men the effect of fear
or momentary anxiety or any intense emotional
interest in causing inhibition of the act can be sup-

INTEERELATIONS OF EMOTIONS 271

ported by cases in the experience of any physician
with extensive practice. Indeed, as Prince ^ has
stated, "the suppression of the sexual instinct by
conflict is one of the most notorious experiences
of this kind in everyday life. This instinct cannot
be excited during an^attack of fear or anger, and
even during moments of its excitation, if there is
an invasion of another strong emotion the sexual
instinct, at once is repressed. Under these con-
ditions, as with other instincts, even habitual
excitants can no longer initiate the instinctive
process."

When the acme of excitement is approachiag it
is probable that the sympathetic division is also
called into activity ; indeed, the completion of the
process — the contractions of the seminal vesicles
and the prostate, and the subsidence of engorged
tissues, all innervated by sympathetic filaments
(see pp. 32, 33) — may be due to the overwhelm-
ing of sacral by sympathetic nervous discharges.
As soon as this stage is reached the original feeling
likewise has been dissipated.

The other parts of the sacral division which
supply the bladder and rectum are so nearly free
from any emotional tone in their normal reflex
functioning that it is unnecessary to consider them
further with reference to emotional antagonisms.
Mild affective states, such as worry and anxiety,
can, to be sure, check the activity of the colon and

272 BODILY CHANGES

thus cause constipation.^ But the augumented
activity of these parts (contraction of the bladder
and rectum) in very intense periods of emotional
stress, when the sympathetic division is strongly
innervated, presents a problem of some difficulty.
Possibly in such conditions the orderliness of the
central arrangements is upset, just as it is after
tetanus toxin or strychnine poisoning, and opposed
innervations no longer discharge reciprocally, but
simultaneously, and then the stronger member of
the pair prevails. Only on such a basis, at pres-
ent, can I offer any explanation for the activity
and the supremacy of the sacral innervation of
the bladder and distal colon when the sympathetic
innervation is aroused, as, for example, in great
fright.

The Function of Hunger

A summary in few words of the chief functions
typically performed or supported by each division
of the autonomic would- desi gnate the cranial divi-
sion as the upbuilder and restorer of the organic
reserves, the sacral as the servant of raciaLgontin-
uity,and the sympathetic as the^pregfirveuaf the in-
dividual. Self-preservation is primary and essen-
tial ; on that depends racial continuity, and for that
all the resources of the organism are called forth.
Analogously the sympathetic innervations, when
they meet in organs innervated also by the cranial

INTERRELATIONS OF EMOTIONS 273

and sacral divisions, almost without exception pre-
dominate over their opponents. And analogously,
also, the emotional states which are manifested in
the sympathetic division and are characteristically
much more intense than those manifested in the
other divisions, readily assume ascendancy also in
consciousness.

It is obvious that extended action of the sym-
pathetic division, abolishing those influences of the
cranial division which are favorable to proper di-
gestion and nutrition, might defeat its own ends.
Interruption of the nutritional process for the sake
of self-preservation through defense or attack can
be only temporary; if the interruption were pro-
longed, there might be serious danger to the vigor
of the organism from failure to replenish the ex-
hausted stores. The body does not have to depend
on the return of a banished appetite, however, be-
fore its need for restoration is attended to. There
is a secondary and very insistent manner in which
the requirement of food is expressed, and that is
through the repeated demands of hunger.

Unlike many other rhythmically repeated sen-
sations, hunger is not one that anybody becomes ac-
customed to and neglects because of its monotony.
During the period of his confioiement in the citadel
of Magdeburg, the celebrated political adventurer
Baron von Trenck * was allowed only a pound
and a half of amraunition bread and a jug of water

274 BODILY CHANGES

as Ms daily ration. "It is impossible for me to
describe to my reader," lie wrote in Ms memoirs,
"the excess of tortures that during eleven months
I endured from ravenous hunger. I could easily
have devoured six pounds of bread every day ; and
every twenty-four hours, after having received
and swallowed my small portion, I continued as
hungry as before I began, yet I was obliged to wait
another twenty-four hours for a new morsel.
. . . My tortures prevented sleep, and looking
into futurity, the cruelty of my fate seemed to me,
if possible, to increase, for I imagined that the pro-
longation of pangs like these was insupportable.
God preserve every honest man from sufferings
like mine! They were not to be endured by the
most obdurate villain. Many have fasted three
days, many have suffered want for a week or more,
but certainly no one besides myself ever endured
it in the same excess for eleven months ; some have
supposed that to eat little might become habitual,
but I have experienced the contrary. My hunger
increased every day, and of all the trials of forti-
tude my whole life has afforded, this eleven months
was the most bitter."*

* In all probability the continued experience of hunger
pangs reported by Baron von Trenck was due to the re-
peated eating of amounts of food too small to satisfy the
bodily demand. The reader will recall that persons who for
some time take no food whatever report that the disagreeable
feelings are less intense or disappear after the third or fourth
day (see p. 238).

INTEERELATIONS OF EMOTIONS 275

Thus, although, the taking of food may be set in
abeyance at times of great excitement, and the
bodily reserves fully mobilized, that phase of the
organism's self-protecting adjustment is limited,
and then hunger asserts itself as an agency im-
periously demanding restoration of the depleted
stores.

The Similarity of Visceral Effects nsr Different Strong

Emotions and Suggestions as to its Psychological

Significance

The dominant emotions which we have been con-
sidering as characteristically expressed in the
sympathetic division of the autonomic system are
fear and rage. These two emotions a're not unlike.
As James ^ has indicated, "Fear is a reaction
aroused by the same objects that arouse ferocity,
. . . We both fear and wish to kill anything
that may kill us ; and the question which of the two
impulses we shall follow is usually decided by some
one of those collateral circumstances of the par-
ticular case, to be moved by which is the mark of
superior mental natures." The. cornering of an
animal when in the headlong flight of fear may
suddenly turn the fear to fury and the flight to a
fighting in which all the strength of desperation
is displayed.

Furthermore, these dominant emotions are states
into which many other commonly milder affective
states may be suddenly transformed. As McDou-

276 BODILY CHANGES

gall® has pointed out, all instinctive impulses
when met with opposition or obstruction give place
to, or are complicated by, the pugnacious or com-
bative impulse directed against the source of the
obstruction. A dog will bristle at any attempt to
take away his food, males will fight furiously when
provoked by interference with the satisfaction of
the sexual impulse, a man will forget the conven-
tions and turn hot for combat when there is impu-
tation against his honor, and a mother all gentle
with maternal devotion is stung to quick resent-
ment and will make a fierce display of her com-'
bative resources, if anyone intentionally injures
her child. In these instances of thwarted or dis-
turbed instinctive acts the emotional accompani-
ments — such as the satisfaction of food and of
sexual affection, the feeling of self -pride, and the
tender love of a parent — are whirled suddenly into
anger. And anger in one is likely to provoke
anger or fear in the other who for the moment is
the object of the strong feeling of antagonism.
Anger is the emotion preeminently serviceable
for the display of power, and fear is often its
counterpart.
J The visceral changes which accompany fear and
rage are the result of discharges by way of sym-
pathetic neurones. It will be recalled that these
neurones are arranged for diffuse rather than for
narrowly directed effects. So far as these two

INTERRELATIONS OF EMOTIONS 277

quite different emotions are concerned, present
physiological evidence indicates that differences
in vis ceral acc ompaniments* are not noteworthy —
for example, either fear or rage stops gastric se-
cretion (see pp. 10, 11). There is, indeed, obvious
reason why the visceral changes in fear and rage
should not be different, but rather, why they should
be alihe. As already pointed out, these emotions
accompany organic preparations for action, and
just because the conditions which evoke them are
likely to result in flight or conflict (either one
requiring perhaps the utmost struggle), the bodily
needs in either response are precisely the same.

In discussing the functioning of the sympathetic
division I pointed out that it was roused to ac-
tivity not only in fear and rage, but also in pain.
The machinery of this division likewise is oper-
ated wholly or partially in emotions which are
usually mild — such as joy and sorrow and disgust

*Obvious vascular differences, as pallor or flushing of the
face, are of little significance. With increase of blood pres-
sure from vasoconstriction, pallor might result from action of
the constrictors in the face, or flushing might result because
constrictors elsewhere, as, for example, in the abdomen, raised
the pressure so high that facial constrictors are overcome.
Such, apparently, is the effect of adrenin already described
(see p. 107). Or the flushing might occur from local vasodila-
tion. That very different emotional states may have the same
vascular accompaniments was noted by Darwin (The Expres-
sion of Emotions in Man and Animals, New York, 1905),
who mentioned the pallor of rage (p. 74) and also of terror
(p. TT).

■y

278 BODILY CHANGES

— when they become sufficiently intense. Thus,
for instance, the normal course of digestion may
be stopped or quite reversed in a variety of these
emotional states. ^/

Darwin "^ reports the case of a young man who
on hearing that a fortune had just been left him,
became pale, then exhilarated, and after various
expressions of joyous feeling vomited the half-
digested contents of his stomach. Miiller ^ has
described the case of a young woman whose lover
had broken the engagement of marriage. She
wept in bitter sorrow for several days, and during
that time vomited whatever food she took. And
Burton,^ in his Anatomy of Melancholy, gives
the following instance of the effect of disgust : "A
gentlewoman of the same city saw a fat hog cut
up, when the entrails were opened, and a noisome
savour offended her nose, she much misliked, and
would not longer abide; a physician in presence
told her, as that hog, so was she, full of filthy ex-
crements, and aggravated the matter by some
other loathsome instances, insomuch this nice gen-
tlewoman apprehended it so deeply that she fell
forthwith a vomiting, was so mightily distempered
in mind and body, that with all his art and persua-
sion, for some months after, he could not restore
her to herself again, she could not forget or remove
the object out of her sight."

In these three cases, of intense joy, intense sor-

INTEREELATIONS OF EMOTIONS 279

row and intense disgust, the influence of the cran-
ial division of the autonomic has been overcome,
digestion has ceased, and the stagnant gastric
contents by reflexes in striated muscles have been
violently discharged. The extent to which under
such circumstances other effects of sympathetic
impulses may be manifested, has not, so far as I
know, been ascertained.

^ From the evidence just given it appears that'
any high degree of excitement in the central nerv-
ous system, whether felt as anger, terror, pain,
anxiety, joy, grief or deep disgust, is likely to
break over the threshold of the sympathetic divi-
sion and disturb the functions of all the organs
which that division innervates. It may be that
there is advantage in the readiness with which
these widely different emotional conditions can ex-
press themselves in this one division, for, as has
been shown (see p. 276), occasions may arise when
these milder emotions are suddenly transmuted
into the naturally intense types (as fright and
fury) which normally activate this division; and
if the less intense can also influence it, the physio-
logical aspect of the transmutation is already par-
tially accomplished. V
/> If various strong emotions can thus be expressed
in the diffused activities of a single division of the
autonomic — the division which accelerates the ,
heart, inhibits the movements of the stomach and

280 BODILY CHANGES

intestines, contrasts the blood vessels, erects the
hairs, liberates sugar, and discharges adrenin — it
would appear that the bodily conditions which have
/ been assumed, by some psychologists, to distin-
guish emotions from one another must be sought
for elsewhere than in the viscera. "We do not "feel
sorry because we cry," as James contended, but
we cry because when we are sorry or overjoyed or
violently angry or full of tender affection — ^when
any one of these diverse emotional states is present
— there are nervous discharges by sympathetic
channels to various viscera, iacluding the lachry-
mal glands. In terror and rage and intense elation,
for example, the responses in the viscera seem too
uniform to offer a satisfactory means of distin-
guishing states which, in man at least, are very
different in subjective quality. For this reason I
am inclined to urge that the visceral changes mere-
ly contribute to an emotional complex more or less
indefinite, but still pertinent, feelings of disturb-
ance in organs of which we are not usually con-
scious.

This view that the differential features of emo-
tions are not to be traced to the viscera is in accord
Iwith the experimental results of Sherrington,^"
I who has demonstrated that emotional responses
occur in dogs in which practically all the main vis-
cera and the great bulk of skeletal muscle have
been removed from subjection to and from influ-

INTEEEELATIONS OF EMOTIONS 281

ence upon the brain, by severance of tbe vagus
nerves and the spinal cord./^In these animals no
alteration whatever was noticed in the occurrence,
under appropriate circumstances, of characteristic
expressions of voice and features, indicating anger,
delight or fear. The argument that these expres-
sions may have been previously established by af-
ferent impulses from excited viscera was met by
noting that a puppy only nine weeks old also con-
tinued to exhibit the signs of emotional excitement
after the brain was disconnected from all the body
except the head and shoulders. Evidence from uni-
formity of visceral response and evidence from ex-
clusion of the viscera are harmonious, therefore, in
minimizing visceral factors as the source of differ-
ences ia emotional states.* ^

If these differences are dtie tb other than vis-
ceral changes, why is it not always possible by vol-
untary innervations to produce emotions ? We can
laugh and cry and tremble. But forced laughter
does not bring happiness, nor forced sobbing sor-
row, and the trembling from cold rouses neither
anger nor fear. The muscle positions and tensions
are there, but the experiencing of such bodily

changes does not seem eve%approximatefy to rouse

J- ' ■

* The paucity of afferent fibres in the autonomic system,
and the probability of an extremely low degree of sensitive-
ness in the viscera (:^or evidence, see Cannon: The Mechan-
ical Factors of Digestion, London, 1911, p. 202), likewise sup-
port this conclusion.

V

282 BODILY CHANGES

an emotion in us. Woluntary assumption of an at-
titude seems to leave out the "feeling." It is prob-
able, however, that no attitude which we can assume
has all the elements in it which appear in the com-
plete response to a stirring situation. But is not this
because the natural response is a pattern reaction,
like inborn reflexes of low order, such as sneez-
ing, in which impulses flash through peculiarly co-
operating neurone groups of the central system,
suddenly, unexpectedly, and in a manner not ex-
actly reproducible by volition, and thus they throw
the skeletal muscles into peculiar attitudes and, if
sufficiently intense, rush out in diffuse discharges
that cause tremors and visceral perturbations?
i The typical facial and bodily expressions, automat-
'ically assumed in different emotions, indicate the
discharge of peculiar groupings of neurones in the
several affective states. That these responses oc-
cur instantly and spontaneously when the appro-
priate "situation," actual or vividly imagined, is
present, shows that they are ingrained in the nerv-
ous organization. A- At least one such pattern, that
of anger, persists after removal of the cerebral
hemispheres — the decorticated dog, by growling
and biting when handled, has the appearance of
being enraged ;^^ the decerebrate cat, when vig-
orously stimulated, retracts its lips and tongue,
stares with dilated pupils, snarls and snaps its
jaws,^^ On the other hand, stroking the hair,

INTEEEELATIONS OF EMOTIONS 283

whistling and gently calling to produce a pleased
attitude, or yelling to produce fright, have not the
slightest effect in evoking from the decorticated
dog signs of joy and affection or of fear, nor does
the animal manifest any sexual feeling. The ab-
sence of bodily indications of these emotions is
quite as significant as the presence of the signs of
anger. For since expressions of anger can persist
without the cerebral cortex, there is little reason
why the complexes of other emotional expressions,
if their "machinery" exists below the cortex, should
not also be elicitable. That they are not elicitable
Suggests that they require a more elaborately or-
ganized grouping of neurones than does anger —
possibly what the cortex, or the cortex in combi-
nation with basal ganglia, would provide.

The contrast between the brevity of the "pseudo-
affective reactions" in the decerebrate eat, though
the viscera are still connected with the central
nervous system, and the normal duration of emo-
tional expression in the dog with the body sepa-
rated from the head region, has been used by Sher-
rington to weigh the importance of the visceral and
other factors. And the evidence which I have given
above, as well as that which he has offered, favors
the view that the viscera are relatively unimpor-
tant in an emotional complex, especially in con-
tributing differential features.

284 BODILY CHANGES

EEFERENOES

1 James : Principles of Psychology, New York, 1905, i,
p. 22.

2 Prince : The Unconscious, New York, 1914, p. 456.

^ Hertz : Constipation and Allied Intestinal Disorders,
London, 1909, p. 81.

* V. Trenck : Merkwiirdige Lebensgeschichte, Berlin, 1Y8Y,
p. 195.

^ James, Loc. cit., p. 415.

^ McDougall : Introduction to Social Psychology, London,
1908, p. 72.

' Darwin : Loc. cit., p. 76.

^ Miiller : Deutsches Archiv fiir klinische Medicin, 1907,
Ixxxix, p. 434.

^ Burton : The Anatomy of Melancholy (first published in
1621), London, 1886, p. 443.

^° Sherrington : Proceedings of the Eoyal Society, 1900,
Ixvi, p. 397.

^^ Goltz : Archiv fiir die gesammte Physiologie, 1892, li,
p. 577.

^^ Woodworth and Sherrington : Journal of Physiology,
1904, xxxi, p. 234.

CHAPTEE XV

ALTEENATIVE SATISFACTIONS FOE THE
FIGHTING EMOTIONS

The uniformity of visceral responses when al-
most any feelings grow very intense, and under
such conditions the identity of these responses
with those characteristically aroused in the bel-
ligerent emotion of anger or rage and its counter-
part, fear, offer iateresting possibilities of trans-
formation and substitution. This is especially
true in the activities of human beings. And be-
cause men have devised such terribly ingenious and
destructive modes of expressing these feelings in
war, an inquiry into the basis for possible substi-
tution seems not out of place.

Support for the Militarist Estimate of the Strength of
THE Fighting Emotions and Instincts

The business of killing and of avoiding death
has been one of the primary interests of living
beings throughout their long history on the earth.
It is in the highest degree natural that feelings of

285

286 BODILY CHANGES

hostility often burn with fierce intensity, and then,
with astonishing suddenness, that all the powers of
the body are called into action — for the strength
of the feeliags and the quickness of the response
measure the chances of survival in a struggle
where the issue may be life or death. These are
the powerful emotions and the deeply ingrained
instinctive reactions which invariably precede com-
bat. They are the emotions and instincts that
sometimes seize upon individuals in groups and
spread like wildfire into larger and larger aggre-
gations of men, until vast populations are shout-
tag and clamoring for war. To whatever extent
military plans are successful in devising a vast
machine for attack or defense, the energies that
make the machine go are found, in the last analysis,
in human beings who, when the time for action
comes, are animated by these surging elemental
tendencies which assume control of their conduct
and send them madly into conflict.

The strength of the fighting instinct in man has
been one of the main arguments used by the mili-
tarists in support of preparation for international
strife. They point to the historical fact that even
among highly civilized peoples scarcely a decade
passes without a kindling of the martial emo-
tions, which explode in actual warfare. Such fight-
ing, they say, is inevitable — the manifestation of
"biological law" — and, so long as human nature

FIGHTING EMOTIONS 287

remains imclianged, decision by battle must be re-
sorted to. They urge, furthermore, that in war
and in the preparations for war important phys-
ical qualities — sturdiness, hardihood, and strength
for valorous deeds — are given peculiarly favorable
opportunities for development, and that if these op-
portunities are lacking, lusty youth will give place
to weaklings and mollycoddles. In addition the
militarists say that war benefits mankind by its
moral effects. Without war nations become effete,
their ideals become tarnished, the people sink into
self-indulgence, their wills weaken and soften in
luxury. "War, on the contrary, disciplines charac-
ter, it sobers men, it teaches them to be brave and
patient, it renews a true order of values, and its de-
mand for the supreme sacrifice of life brings forth
in thousands an eager response that is the crown-
ing glory of the human spirit. As the inevitable
expression of a deep-rooted instruct, therefore, and
as a unique means of developing desirable physical
and moral qualities, war is claimed by the mili-
tarists to be a natural necessity.^

The militarist contention that the fighting in-
stinct is firmly fixed in human nature receives
strong confirmation in the results of our re-
searches. Survival has been decided by the grim
law of mortal conflict, and the mechanism for ren-
dering the body more competent in conflict has been
revealed in earlier chapters as extraordinarily per-

288 BODILY CHANGES

feet and complete. Moreover, the physiological
provisions for fierce struggle are found not only in
the bodies of lower animals, that must hunt and
kill in order to live, but also in human beings.
Since this remarkable mechanism is present, and
through countless generations has served the fun-
damentally important purpose of giving momen-
tous aid in the struggle for existence, the mili-
tarists might properly argue that, as with other
physiological processes, bodily harmony would be
promoted by its exercise. Indeed, they might
account for the periodic outburst of belligerent
feelings by assuming that these natural aptitudes
require occasional satisfaction.*

Growing Opposition to the Fighting Emotions and Instincts
AS Displayed in Wak

In spite of the teachings of history that wars
have not grown fewer, and in spite of the militarist
argument that war is a means of purging mankind
of its sordid vices, and renewing instead the no-
blest virtues, the conclusion that the resort to arms
is unavoidable and desirable is nowadays being
strongly contested. The militarists show only

* Mr. Graham Wallas has made the interesting sugges-
tion (The Great Society, New York, 1914, p. 66) that nerv-
ous strain and restlessness due to "baulked disposition" may
result from the absence of circumstances which would call
the emotional responses into action. And he cites Aristotle's
theory that pent passions may be released by represented
tragedy and by music.

FIGHTING EMOTIONS 289

part of the picture. No large acquaintance with
the character of warfare is necessary to prove that
when elemental anger, hate and fear prevail,
civilized conventions are abandoned and the most
savage instincts determine conduct. Homes are
looted and burned, women and children are
abominably treated, and many innocents are
murdered outright or starved to death. No bland
argument for the preservation of the manly
virtues can palliate such barbarities. Even when
fighting men are held within the rules, the de-
vices for killing and injuring are now made
so perfect by devilish ingenuity that by the
pulling of a trigger one man can in a few seconds
mow down scores of his fellow-creatures and send
them writhing to agony or death. War has become
too horrible; it is conducted on too stupendous a
scale of carnage and expenditure; it destroys too
many of the treasured achievements of the race ; it
interferes too greatly with consecrated efforts to
benefit all mankind by discovery and invention ; it
involves too much suffering among peoples not di-
rectly concerned in the struggle ; it is too vastly at
variance with the methods of fair dealing that have
been established between man and man ; the human
family has become too closely knit to allow some
of its members to bring upon themselves and all
the rest poverty and distress and a long heritage
of bitter hatred and resolution to seek revenge.

290 BODILY CHANGES

All these reasons for hostility to war imply a
thwarting of strong desires in men — desires for
family happiness, devotion to beauty and to schol-
arship, passion for social justice, hopes of lessen-
ing poverty and disease. As was pointed out in
the previous chapter, the feeling of hostility has no
definite object to awaken it. It is roused when
there is opposition to what we ardently wish to get.
And because war brings conditions which frustrate
many kinds of eagerly sought purposes, war has
roused in men a hostility against itself. There is
then a war against war, a willingness to fight
against monstrous carnage and destruction, that
grows in intensity with every war that is waged.

The Desirability of Preserving the Martial Virtues

Although there is increasing opposition to the
display of the fighting emotions and instincts in
war, nevertheless the admirable moral and phys-
ical qualities, claimed by the militarists to be the
unique products of war, are too valuable to be lost.
As McDougall ^ has indicated, when the life of
ideas becomes richer, and the means we take to
overcome obstructions to our efforts more refined
and complex, the instinct to fight ceases to express
itself in its crude natural manner, save when most
intensely excited, and becomes rather a source of
increased energy of action towards the end set by
any other instinct ; the energy of its impulses adds

FIGHTING EMOTIONS 291

itself to and reenforces that of other impulses and
so helps us to overcome our difficulties. In this
lies its great value for civilized man. A man de-
void of the pugnacious instinct would not only be
incapable of anger, but would lack this great source
of reserve energy which is called into play in most
of us by any difficulty in our path.

Thus the very efficiency of a war against war, as
well as struggle against other evils that beset civil-
ized society, rests on the preservation and use of
aggressive feeling and the instinct to attack. From ,
this point of view the insistence by the militarists
that we must accept human nature as we find it,
and that the attempt to change it is foolish, seems
a more justifiable attitude than that of' the paci-
fists who belittle the fighting qualities and urge
that changing them is a relatively simple process.
We should not wish them changed. Even if in the
war against war a means should be established of
securing international justice, and if through co-
operative action the decrees of justice were en-
forced, so that the occasions which would arouse
belligerent emotions and instincts were much re-
duced, there would still remain the need of recog-
nizing their elemental character and their possible
■ usefulness to society. What is needed is not a
suppression of these capacities to feel and act, but
their diversion into other channels where they may
have satisfactory expression.

292 BODILY CHANGES

Moral Substitutes for Warfare

"We must make new energies and hardihoods
continue the manliness to which the military mind
so faithfully clings. Martial virtues must be the
enduring cement; intrepidity, contempt of soft-
ness, surrender of private interest, obedience to
command, must still remain the rock upon which
states are built." Thus wrote "William James ^
in proposing a "moral equivalent for war." This,
he suggested, should consist of such required serv-
ice in the hard and difficult occupations as would
take the childishness and superciliousness out of
our youth and give them soberer ideas and health-
ier sympathies with their fellow-men. He con-
ceived that by proper direction of its education a
people should become as proud of the attainment
by the nation of superiority in any ideal respect
as it would be if the nation were victorious in war.
"The martial type of character," he declared, "can
be bred without war. Strenuous honor and disin-
terestedness abound elsewhere. Priests and medi-
cal men are in a fashion educated to it, and we
should all feel some degree of it imperative if we
were conscious of our work as an obligatory serv-
ice to the state. We should be oivned, as soldiers
are by the army, and our pride would rise ac-
cordingly. We could be poor, then, without
humiliation, as army officers now are. The only
thing needed henceforth is to inflame the civic

FIGHTING EMOTIONS 293

temper as past history has inflamed the military
temper."

Similar ideas have been expressed by others.*
It has been pointed out that the great war of man-
kind is that against pain, disease, poverty and sin ;
that the real heroes are not those who squander hu-
man strength and courage in fighting one another,
but those who fight for man against these his eter-
nal foes. War of man against man, in this view,
becomes dissension ia the ranks, permitting the
common enemies to strike their most telling blows.

These moral considerations, however, are apart
from the main intent of our discussion. Our ear-
lier inquiry confirmed the belief that the fighting
emotions are firmly rooted in our natures, and
showed that these emotions are intimately asso-
ciated with provisions for physical exertion. It
is particularly in this aspect of the discussion of
substitutes for war that these studies have sig-
nificance.

Physical Substitutes for Warfare

The idealization of the state and the devotion
of service to social welfare, which have been sug-
gested as moral substitutes for military loyalty,
leave unanswered the claims of the militarists
that in war and in preparations for war oppor-
tunities are offered which are peculiarly favorable
to the development of important physical qualities

294 BODILY CHANGES

■ — ^bodily vigor, sturdiness, and ability to with-
stand all manner of hardships.

In the evidence previously presented, it seems
to me there was a suggestion that offers a perti-
nent alternative to these claims. When the body
goes onto what we have called a war footing, the
physiological changes that suddenly occur are
all adapted to the putting forth of supreme mus-
cular and nervous efforts. That was what primi-
tive battle consisted of, through countless myriads
of generations — a fierce physical contest of beast
with beast, and of man with man. Such contests,
attended as they were by the thrill of unpredict-
able incidents, and satisfying completely the lust
of combat, are to be contrasted with the dull grind
in preparation for modern war, the monotonous
regularity of subservience, the substitution every-
where of mechanism for muscle, and often the
attack on an enemy who lies wholly unseen.* As

* Lord Wolseley, while commander-in-chief of the English
forces, in 1897, secured sanction for not displaying the regi-
mental colors in battle. "It would be madness and a crime,"
he declared, "to order any soldier to carry colors into action
in the future. You might quite as well order him to be as-
sassinated. We have had most reluctantly to abandon a
practice to which we attached great importance, and which,
tinder past and gone conditions of fighting, was invaluable in
keeping alive the regimental spirit upon which our British
troops depended so much." All was has been transformed by
the invention of the far-reaching and fate-dealing rifle and
automatic gun, with which an enemy kills, whose face is not
even seen. War is almost reduced to a mechanical inter-

FIGHTING EMOTIONS 295

Wallas witli nice irony has remarked, "The gods
ia Valhalla would hardly choose the organization
of modem lines of military communication, as
they chose the play of sword and spear, to be the
most exquisite employment of eternity."

While it is true that physical strength can be
developed by any form of hard labor, as, for
example, by sawing wood or digging ditches, such
labor does not stimulate quickness, alertness, and
resourcefulness in bodily action. Nor does it give
any occasion for use of the emotional mechanism
for reenforcement. If this mechanism, like other
physiological arrangements, is present in the
body for use — and previous discussion leaves little

change of volleys and salvoes, and to the intermittent fire of
rifles and machine guns, with short rushes at the last, in
which there is no place for the dignity and grace of the
antique battle of the standard. (See London Times, July 31,
189Y, p. 12.)

T. r. Millard, the well-known correspondent of the Russo-
Japanese War, wrote as follows of the characteristics of
present day conflicts : "A largje part of modern war is on
too great a scale to give much opportunity for individual
initiative. Soldiers can rarely tell what is going on in their
immediate vicinity. They cannot always see the enemy they
are firing at, and where they can see the object of their fire
such an important matter as range and even direction can-
not be left to them. . . . Troops are clothed so much alike
nowadays that it is very difficult to distinguish friend from
foe at five hundred yards, and large bodies of troops rarely
get that close to each other in modern war while there is
light enough to see clearly. . . . Battery officers simply see
that their guns are handled according to instructions. They

296 BODILY CHANGES

doubt of that — then as a means of exercising it
and, in addition, satisfying the strong instinct for
competitive testing of strength and physical skill,
some activity more enlivening than monotonous
gymnastics and ordered marching is required.

In many respects strenuous athletic rivalries
present, better than modern military service, the
conditions for which the militarists argue, the
conditions for which the body spontaneously pre-
pares when the passion for fighting prevails. As
explained in an earlier chapter, in competitive
sports the elemental factors are retained — man
is again pitted against man, and all the resources
of the body are summoned in the eager struggle

regulate the time, speed, objective and range as ordered. . . .
The effects of the fire are observed by officers appointed to
that duty, stationed at various parts of the field, often miles
and miles apart, and who are in constant communication
with the chief of artillery by telephone." (See Scribner's
Magazine, 1905, xxxvii, pp. 64, 66.)

The testimony of a captain of a German battery engaged
against the French and English in 1914, supports the forego-
ing claims. He is reported as saying : "We shoot over those
tree tops yonder in accordance with directions for range and
distance which come from somewhere else over a field tele-
phone, but we never see the men at whom we are firing.
They fire back without seeing us, and sometimes their shells
fall short or go beyond us, and sometimes they fall among us
and kill and wound a few of us. Thus it goes on day after
day. I have not with my own eyes seen a Frenchman or an
Englishman unless he was a prisoner. It is not so much
pleasure — fighting like this." (See Philadelphia Saturday
Evening Post, December 26, 1914, p. 2Y.)

FIGHTING EMOTIONS 297

for victory. And because, tmder such circum-
stances, the same physiological alterations occur
that occur in anticipation of mortal combat, the
belligerent emotions and instincts, so far as their
bodily manifestations are concerned, are thereby
given complete satisfaction.

The Significance of International Athletic Competitions

For reasons given above, I venture to lay em-
phasis on a suggestion, which has been made
before by others, that the promotion of great inter-
national athletic contests, such as the Olympic
games, would do for our young men much that is
now claimed as peculiar to the values of military
discipline. The substitution of athletic rivalries
for battle is not unknown. In the Philippine Isl-
ands, according to Worcester,^ there were no
athletics before the American occupation. The
natives soon learned games from the soldiers,
j^nd when the sports reached such development
that competition between towns and provinces was
possible, they began to arouse the liveliest enthu-
siasm among the people. The physical develop-
ment of the participants has been greatly stimu-
lated, the spirit of fair play and sportsmanship,
formerly lacking, has sprung into existence in
every section of the Islands, and the annual meets
between athletic teams from various provinces are
recognized as promoting a general and friendly

298 BODILY CHANGES

understanding among the different Filipino tribes.
The fierce Igarots of Bontoc, once constantly at
war with neighboring tribes, now show their prow-
ess not in head-hunting, but in baseball, wrestling,
and the tug-of-war.*

Is it unreasonable to expect that what has hap-
pened in the Philippine Islands might, by proper
education and suggestion, happen elsewhere in the
world? Certainly the interest in athletic contests
is no slight and transient interest. At the time
of a great war we know that news of the games
is fully as much demanded as news of the war.
Already in the United States, without special
stimulation, the number of young men engaged in
athletic training is estimated as equal to the num-
ber in the standing army. And in England, belief
in the efficacy of athletics as a means of promoting
hardihood and readiness to face stern hazards has
found expression in the phrase that England's
battles have been won on the football fields of
Eugby and of Eton. With the further promotion
of international contests the influence of competi-
tive sports is likely to increase rather than lessen.
Within national boundaries emulation is sure to
stimulate extensively such games as will bring
forth the best representative athletes that the coun-

* It is reported that when these warriors first appeared at
the games, each brought his spear, which he drove into the
ground beside him, ready for use. As the nature of the new
rivalries became known, the spears were left behind.

FIGHTING EMOTIONS 299

try can produce. In one of tlie high-spirited Eu-
ropean nations, which made a poor showing at the
last Olympic meet, thousands of young men began
training for the next meet, under a director im-
ported from the nation that had made the highest
records.

Training for athletic contests is quite as likely
to enure young men to physical hardship and
fatigue, is quite as conducive to the development
of bodily vigor, the attainment of alertness and
skill and the practice of self-restraint, as is army
life with its traditional associations and easy li-
cense. It may be urged, however, that an essential
element is lacking in all this discussion — the so-
bering possibility that in war the supreme sur-
render of life itself may be required. Death for
one's country is indeed glorious. But the argu-
ment that being killed is desirable has little to
commend it. When the strongest and sturdiest are
constantly chosen to be fed to the engines of anni-
hilation, the race is more likely to lose greater
values than it gains from the spectacle of self-
sacrifice, however perfect that may be. Are there
not advantages in the conditions of great athletic
rivalries that may compensate for war's most aus-
tere demand? The race of hardy men, to secure
which the militarists urge war, is much more likely
to result from the honoring and preserving of
vigorous men in their vigor than it is from the

300 BODILY CHANGES

systematic selection of such, men to be destroyed
in their youth.

There are other aspects of international games
which strongly commend them as an alternative
to the pursuit of military discipline. The high
standards of honor and fairness in sport ; its un-
failing revelation of excellence without distinc-
tions of class, wealth, race or color ; the ease with
which it becomes an expression of the natural
feelings of patriotism; the respect which victory
and pluckily borne defeat inspire in competitors
and spectators alike; the extension of acquaint-
ance and understanding which follows from
friendly and magnanimous rivalry among strong
men who come together from the ends of the earth'
— each of these admirable features of athletic eon-
tests between nations might be enlarged upon.
But, as intimated before, these moral considera-
tions must be left without further mention, as
being irrelevant to the physiological processes
with which we are dealing.

"We are concerned with the question of exercis-
ing the fighting instinct and thus assuring the
physical welfare of the race. The race must de-
generate, the militarists say, if this instinct is
not allowed to express itself in war. This declar-
ation we are in a position to deny, for the evi-
dence is perfectly clean-cut that the aggressive
instincts, which through aeons of racial experi-

FIGHTING EMOTIONS 301

ence have naturally and spontaneously developed
vigor and resourcefulness in the body, are invited
by elemental emotions, and that through these
emotions energies are released which are highly
useful to great physical effort. No stupid routine
of drill, or any other deadening procedure, will
call these energizing mechanisms into activity.
War and the preparations for war nowadays have
become too machine-like to serve as the best means
of preserving and disciplining these forces. The
exhilarating swing and tug and quick thrust of the
big limb muscles have largely vanished. Pressing
an electric contact or bending the trigger finger
is a movement altogether too trifling. If, then,
natural feelings must be expressed, if the fight-
ing functions of the body must be exercised,
how much better that these satisfactions be found
in natural rather than in artificial actions, how
much more reasonable that men should struggle
for victory in the ancient ways, one against an-
other, body and spirit, as in the great games.

EEEERENCES

^ See Angell : The Great Illusion, New York and London,

1913, pp. 159-164.

^McDougall: Introduction to Social Psychology, London,
1908, p. 61.

^ James : Memories and Studies, New York, 1911, p. 287.

* See Perry : : The Moral Economy, New York, 1909, p. 32 ;
and Drake : Problems of Conduct, Boston, 1914, p. 317.

^ Worcester : The Philippines, Past and Present, New York,

1914, ii, pp. 515, 578.

A LIST OF PUBLISHED EESEAEOHES FROM THE
PHYSIOLOGICAL LABORATORY IN HARVARD
UNIVERSITY, ON WHICH THE PRES-
ENT ACCOUNT IS BASED.

1. The Influence of Emotional States on the Functions of
the Alimentary Canal. By W. B. Cannon. American Jour-
nal of the Medical Sciences, 1909, cxxxvii, pp. 480-487.

2. Emotional Stimulation of Adrenal Secretion. By W. B.
Cannon and D. de la Paz. American Journal of Physiology,
1911, xxviii, pp. 64-70.

3. The Effects of Asphyxia, Hyperpnoea, and Sensory
Stimulation on Adrenal Secretion. By W. B. Cannon and
R. G. Hoskins. Ibid., 1911, xxix, pp. 274-279.

4. Emotional Glycosuria. By W. B. Cannon, A. T. Shohl
and W. S. Wright. Ihid., 1911, xxix, pp. 280-287.

5. A Consideration of Some Biological Tests for Epi-
nephrin. By R. G. Hoskins. Journal of Pharmacology and
Experimental Therapeutics, 1911, iii, pp. 93-99.

6. The Sthenic Effect of Epinephrin upon Intestine. By
R. G. Hoskins. American Journal of Physiology, 1912, xxix,
pp. 363-366.

7. An Explanation of Hunger. By W. B. Cannon and A.
L. Washburn. Ibid., 1912, xxix, pp. 441-454.

8. A New Colorimetric Method for the Determination of
Epinephrin. By 0. Folin, W. B. Cannon and W. Denis.
Journal of Biological Chemistry, 1913, xiii, pp. 477-483.

9. The Depressor Effect of Adrenalin on Arterial Pressure.
By W. B. Cannon and Henry Lyman. American Journal of
Physiology, 1913, xxxi, pp. 376-398.

302

PUBLISHED EESEAECHES 303

10. The Effect of Adrenal Secretion on Muscular Fatigue.
By W. B. Cannon and L. B. Nice. Ihid., 1913, xxxii, pp.
44-60.

11. Fatigue as Affected by Changes of Arterial Pressure.
By 0. M. Gruber. Ihid., 1913, xxxii, pp. 222-229.

12. The Threshold Stimulus as Affected by Fatigue and
Subsequent Best. By C. M. Gruber. Ibid., 1913, xxxii, pp.
438-449.

13. The Fatigue Threshold as Affected by Adrenalin and
by Increased Arterial Pressure. By C. M. Gruber. Ihid.,
1914, xxxiii, pp. 335-355.

14. The Emergency Function of the Adrenal Medulla in
Pain and the Major Emotions. By W. B. Cannon. Ihid.,
1914, xxxiii, pp. 356-372.

15. The Relation of Adrenalin to Curare and Fatigue in
Normal and Denervated Muscles. By C. M. Gruber. Ihid.,
1914, xxxiv, pp. 89-96.

16. The Graphic Method of Recording Coagulation. By
W. B. Cannon and W. L. Mendenhall. Ihid., 1914, xxxiv,
pp. 225-231.

lY. The Hastening or Retarding of Coagulation by
Adrenalin Injections. By W. B. Cannon and Horace Gray.
Ihid., 1914, xxxiv, pp. 232-242.

18. The Hastening of Coagulation by Stimulating the
Splanchnic Nerves. By W. B. Cannon and W. L. Menden-
hall. Ihid., 1914, xxxiv, pp. 243-250.

19. The Hastening of Coagulation in Pain and Emotional
Excitement. By W. B. Cannon and W. L. Mendenhall.
Ihid., 1914, xxxiv, pp. 251-261.

20. The Interrelations of Emotions as Suggested by Recent
Physiological Researches. By W. B. Cannon. American
Journal of Psychology, 1914, xxv, pp. 256-282.

INDEX

Adrenal extract : effect of,
on muscular contraction,
82.

Adrenal glands : nerve sup-
ply of, 37; stimulated in
emotion, 52-59, 62-63 ;
stimulated in pain, 59-62,
63; in relation to blood
sugar, 77; removal of,
causes muscular weakness,
81; secretion of, improves
contraction of fatigued
muscle, 92; variations in
adrenin content of, 171;
latent period of, when
splanchnics stimulated,
188; amount of secretion
from, when splanchnics
stimulated, 198 ; fatigue of,
199; stimulated by as-
phyxia, 206-208.

Adrenin : secreted by adre-
nal glands, 36; action of,
identical with sympathetic
impulses, 37, 64; secretion
of, by splanchnic stimula-
tion, 41-43; secreted in
emotional excitement, 44,
52-59; method of testing
for, in blood, 47-50; se-
creted in emotion, 52-59,
62-63 ; disappearance of,
from blood, 58 ; secreted in
pain, 59-62, 63; effects of,
when injected into body,
64-65; effect of, on dis-
tribution of blood in the

body, 107; quickly restores
fatigued muscle to normal
irritability, 119-123 ; specific
in its restorative action,
124-128; as an antidote to
muscular metabolites, 129;
restores fatigued denerv-
ated muscle to normal irri-
tability, 130; point of ac-
tion of, in muscle, 128-133 ;
antagonistic to curare, 132 ;
induces rapid coagulation
of blood, 136, 147 ff.; not
the direct cause of rapid
coagulation, 156-158; fails
to shorten coagulation time
in absence of intestines
and liver, 157-158 ; vari-
able amount of, in adrenal
glands, 171 ; emergency
functions of, 185 ff. ; util-
ity of, in bettering the con-
traction of fatigued mus-
cle, 194-195; not a check
to use of sugar in the body,
197, 199; amount of, se-
creted when splanchnics
stimulated, 198 ; a condition
for increase of blood sugar,
199; stimulates the heart,
191, 201; dilates the bron-
chioles, 204; secretion of,
increased in asphyxia, 206-
208.
Amyl nitrite: effect of, on
contraction of fatigued
muscle, 126.

305

306

INDEX

Anger: associated with ac-
tion, 188 ; energizing influ-
ence of, 216.

Antagonisms : autonomic, 34 ;
in relation to emotions, 38 ;
between cranial and sym-
pathetic divisions, 268-270;
between sacral and sympa-
thetic divisions, 270-272.

Appetite : compared with
hunger,. 233, 235; opera-
tion of, after section of
vagus and splanchnic
nerves, 240.

Arterial blood pressure : in-
creased in excitement, 95;
artificial methods of in-
creasing, 97; influence of
different heights of, on
fatigue, 97-102 ; influence
of increase of, on fa-
tigue, 97-102 ; influence
of decrease of, on fa-
tigue, 102, - 104; the
"critical region" in de-
creasing, 104; explanation
of effects on fatigued mus-
cle, of varying, 104-106;
value of increased, in pain
and emotion, 106.

Arteries : innervation of, 26.

Asphyxia: increases adrenal
secretion, 206-208 ; in-
creases sugar in blood, 209.

Athletes : glycosuria of, after
games, 75.

Autonomic nervous system:
three divisions of, 25; ar-
rangement of sympathetic
division of, 26-29 ; arrange-
ment of cranial and sacral
divisions of, 29-30; general
functions of cranial di-
vision of, 30-32; general
functions of sacral division
of, 32-34; antagonism be-
tween sympathetic and
cranial-sacral divisions of.

34-36 ; identity of action of
sympathetic division of,
and adrenal secretion, 36-
38 ; antagonisms between
emotions expressed in, 268-
■ 272.

Behavior : biological explana-
tio^ of, 2.

Bile : flow of, inhibited by
excitement, 13.

Bladder: innervation of, 27,
32; effects of emotions on,
33.

Blood : method of obtaining,
for test for adrenin, 45-46 ;
method of testing, for
adrenin, 47-50; sugar in,
66, 73-74; distribution of,
as affected by adrenin, pain
and excitement, 107-108,
200; functions of, 135;
rapid coagulation of, by
adrenin, 136 ff. ; drawing
of, for testing coagulation
time, 140-142 ; treatment
of, in testing coagulation
time, 142-145 ; faster co-
agulation of, after subcu-
taneous injections of adre-
nin, 147-150, and after in-
travenous injections, 150-
156; oscillations in the
rate of coagulation of,
155 ; rapid coagulation
of, not due directly to ad-
renin, 156-158; rapid co-
agulation of, not caused by
adrenin in absence of liver
and intestines, 157-158,
and not caused by increase
of blood sugar, 159, 170;
coagulation of, hastened
by splanchnic stimulation,
162-167, but not in absence
of adrenal glands, 167-171 ;
possible delay of coagula-
tion of, after stimulatioii

INDEX

307

of hepatic nerves, lYO ; co-
agulation of, hastened by
"painful" stimulation, 172-
177 ; coagulation of, hasten-
ed in light anesthesia, 174-
177; rapid coagulation of,
after excitement, stopped
by severing splanchnic
nerves, 180-182; utility of
increased sugar in, 188-193 ;
distribution of, in pain
and excitement, favorable
to muscular effort, 201;

, sugar in, increased by as-
phyxia, 209 ; utility of
rapid coagulation of, 211.

Bronchioles : dilated by adre-
nin, 204.

Bulimia : explanation of,
262.

Coagulation, see Blood.

Coagulometer : graphic, 138-
147.'

Combat: relation of emotion
and endurance in, 225-
226; nature of ancient,
294.

Constipation: as result of
■worry and anxiety, 271.

Cortex, cerebral: insensitive-
ness of, 242.

Cranial autonomic division;
functions of, to conserve
bodily resources, 30-32,
268 ; activities of, suppress-
ed by activities of ssrm-
pathetic division, 268-
272.

Curare: action of, antago-
nized by adrenin, 132.

Dances: relation of excite-
ment and endurance in,
222-224.

Danger : stimulating effect
of, 230.

Dervishes : exhibitions of en-
durance by, 224.

Digestion : interruption of,
by strong emotion, 9-12,
13-18, 268-269.

Emotions: surface signs of,
3 ; favorable to digestive se-
cretions, 4-8 ; unfavorable
to digestive secretions, 9-
13 ; persistence of effects
of, on digestive secretions,
12; effects of, on gastric
and intestinal contractions,
13-18; in relation to sym-
pathetic division, 36 ; in re-
lation to adrenal secretion,
44, 52-59, 62-63; increase
of blood sugar in, 66, 73;
glycosuria in, 70-76; influ-
ence of, on distribution of
blood in body, 108; faster
coagulation of blood in,
177-182, but stopped by
cutting splanchnics, 180-
182; value of forced res-
piration in, 203; value of
bronchiolar dilation in,
204; relationto action, 215/
displayed in a "pattern"
response, 218, 282; in re-
lation to exhibitions of
power and endurance, 215,
229; antagonisms between
cranial and sympathetic,
268-270, and between sacral
and sympathetic, 270-
272; similarity of visceral
changes in strong, 275-279 ;
dependence of, on cerebral
cortex, 282-283.

Endurance: feats of, related
to great emotion, 217-218;
in the excitements of
mania and dancing, 222-
224; stimulated by music,
228.

Esophagus : contractions of,
associated with hunger sen-
sation, 259-260.

308

INDEX

Fatigue : of muscls, 84 ; mus-
cular, lessened by splanch-
nic stimulation, 89-93; as
affected by increase of ar-
terial pressure, 97-102 ;
irritability of muscle in,
increased by splanchnic
stimulation, 101; explana-
tion of effects of varied ar-
terial pressure on, 104-106 ;
lessens neuro-musculap ir-
ritability, 114-117, 120; ef-
fect of, on curarized mus-
cle, 132; utility of adrenin
in lessening effects of, 194,
195; of adrenal glands,
199; cessation of hunger
contractions in, 262.

Fear: anticipatory character
of, 186-187 ; associated with
action, 188 ; explanation
of paralyzing effect of,
189 ; energizing influence
of, 216; relation to rage,
275; bodily changes in,
like those in rage, 276-277 ;
importance of, as a fight-
ing emotion, 286.

"Fesselungsdiabetes," 69.

Fever : absence of hunger in,
242, 263.

Fighting emotions : bodily
changes in, like those in
competitive sports, 219-221,
296; anger and fear as,
285; importance of, 286;
satisfactions for, in com-
petitive sports, 301.

Food: effect of sight and
smell of, on gastric secre-
tion, 6.

Football: glycosuria in play-
ers of, 75; relation of ex-
citement and power in,
219-221.

Frenzy: endurance in, 223,
224.

Ganglia : autonomic, 23.

Gastric glands : turgescence
of, not the cause of hun-
ger sensation, 249-250.

Gastric juice: psychic secre-
tion of, 5-8, 11 ; importance
of, for intestinal digestion,
7 ; flow of, inhibited by ex-
citement, 9-12, and by
pain, 19.

Generative organs: innerva-
tion of, 32, 33; effects of
strong emotions on activ-
ities in, 271.

Glycosuria: in pain, 69-70;
in emotion, 70-76; after
football, 75, 221; after ex-
aminations, 76 ; depend-
ence of, on adrenal glands,
77.

Heart : innervation of, 26, 31 ;
use of sugar by, 191;
stimulated by adrenin,
191, 201.

Hunger: compared with appe-
tite, 233, 235; description
of, 234-236; theories of,
237 ; as a general sensation,
237; disappearance of, as
time passes, 238-239 ; when
stomach full, 239; may be
absent in bodily need, 242-
243; temporarily abolished
by indigestible materials,
243; quick onset and peri-
odicity of, 244-245; refer-
ence of, to stomach region,
245-247 ; not due to empti-
ness of stomach, 248; not
due to hydrochloric acid in
empty stomach, 248; not
due to turgid gastric
glands, 249-250; as the re-
sult of contractions, 251-
253; inhibited by swallow-
ing, 254 ; method of record-
ing gastric contractions in.

INDEX

309

255-256; associated with
gastric contractions, 256-
259, and with esophageal
contractions, 259 - 260;
function of, 263-264, 272-
275.
Hydrochloric acid: not the
cause of hunger sensation,
248.

Intestine : contractions of,
inhibited by excitement,
16; innervation of, 27, 31;
use of, as test for adrenin
in blood, 47-50; contracts
when empty, 251-253 ; con-
tractions of, may originate
hunger sensations, 263.

Instincts : relation of, to emo-
tions, 187, 188.

Irritability: increased in fa-
tigued muscle by splanch-
nic stimulation, 101 ; neuro-
muscular, lessened by fa-
tigue, 114-117, 120; when
lowered, restored slowly by
rest, 119; when lowered,
restored quickly by adre-
nin, 119-123, 195.

"Jumpers" : exhibition of en-
durance by, 223.

Mania : endurance in, 222.

Martial virtues : claims for,
by militarists, 287 ; import-
ance of preserving, 290-
291; preserved in competi-
tive sports, 297-299.

Metabolites: influence of, on
muscular contraction, 104;
action of, opposed by adre-
nin, 129; increase adrenal
secretion, 206-208.

Militarists: emphasis of, on
strength of fighting in-
stincts, 286-288; claims of,
as to values of war, 287;
support for claims of, 287.

Muscle: weakness of, after
removal of adrenal glands,
81 ; improved contraction
of, after injection of adre-
nal extract, 82; fatigue of,
84; method of recording
fatigue of, 85-86; fatigue
of, lessened by splanchnic
stimulation, 89-93 ; con-
traction of, when fatigued,
improved by increased arte-
rial pressure, 97-102; irri-
tability of, when fatigued,
increased by splanchnic
stimulation, 101 ; contrac-
tion of, when fatigued, less-
ened by decreased arte-
rial pressure, 102-104; ex-
planation of effects of va-
ried arterial pressure on
fatigued, 104-106 ; irritabil-
ity of, decreased in fatigue,
114-117, 120; decreased ir-
ritability of, slowly re-
stored by rest, 117-118, and
quickly restored by adre-
nin, 119-123 ; contraction
of fatigued denervated, in-
creased by adrenin, 130;
point of action of adrenin
in, 128-133; use of , in strug-
gle, 189; energy of, from
carbonaceous material, 190-
193; disappearance of gly-
cogen from, 190; increased
efficiency of, with increase
of blood sugar, 192-193;
utility of adrenin in less-
ening fatigue of, 194-
195 ; efficiency of, increased
by distribution of blood in
pain and excitement, 201.

Music : stimulating influence
of, 227; influence of mar-
tial, 228.

Neurones, autonomic: exten-
sive distribution of sym-

310

INDEX

pathetic, 26; arrangement
of sympathetic for diffuse
action, 28 ; restricted dis-
tribution of cranial and sa-
cral, 29; arrangement for
specific action, 30.

Olympic games: as physical
substitutes for warfare,
297-298.

Operations: in light anes-
thesia hasten coagulation
of blood, 174-177.

"Ordeal of rice," 9.

Pain : disturbing effect of, on
digestion, 18-19; as occa-
sion for adrenal secretion,
59-62, 63; glycosuria in,
69-70; influence of, on
distribution of blood in
body, 108 ; hastens coagu-
lation of blood, 172-177;
reflex nature of responses
in, 185-187; associated
with action, 189 ; stimulat-
ing and depressive effects
of, 189.

Pancreatic juice : flow of, in-
hibited by excitement, 13.

Philippine Islands : substi-
tution of sports for war-
fare in, 297.

Power : the feeling of, 229.

Psychic secretion: of gastric
juice, 5-8, 11; of saliva, 6;
dependent on cranial auto-
nomic innervation, 31.

Psychic "tone" : of gastro-in-
testinal muscles, 13.

Racing: relation of excite-
ment and power in, 221.

Rage: relation of, to fear,
275 ; transformation of
other emotions into, 276;
bodily changes in, like
those in fear, 276-277 ; im-
portance of, as a fighting
emotion, 286.

Reflexes : "purposive" char-
acter of, 185-186.

"Reservoirs of power," 2l6.

Respiration: Utility of in-
creased, in pain and ex-
citement, 202; value of
forced, in lessening dis-
tress, 203.

Rest : restores irritability
lessened by fatigue, 117-
118.

Sacral autonomic division :
functions of, in mechan-
isms for emptying, 32-34;
activities of, suppressed by
activities of sympathetic
division, 270-272.

Saliva : psychic secretion of,
6 ; importance of, for taste,
6 ; flow of, inhibited by ex-
citement, 9.

Salivary glands: innervation
of, by cranial autonomic,
31.

"Second wind": explanation
of, 210.

Sex : instinct of, suppressed
by fear and anger, 271.

"Sham feeding," 5.

Splanchnic nerves: stimula-
tion of, causes adrenal se-
cretion, 41-43; method of
stimulating, 87-88; stimu-
lation of, improves contrac-
tion of fatigued muscle,
89; stimulation of, hast-
ens coagulation of blood,
162-167, but not in absence
of adrenal glands, 167-171 ;
severance of, stops rapid
coagulation following ex-
citement, 180-182 ; eating
after severance of, 240.

Sports : relation of excite-
ment and power in, 219-
221, 296; as physical sub-
stitutes for warfare, 297-

INDEX

311

301; moral values of, 300.

Stomach: psychic tonus of,
13 ; contractions of, inhib-
ited by excitement, 14-15,
11, and by pain, 19; in-
nervated by sympathetic
neurones, 2Y, and by cra-
nial autonomic, 31; refer-
ence of hunger sensation
to, 245-24Y; emptiness of,
not the cause of hunger,
248; contractions of, when
empty, 251-253; method of
recording contractions of,
255-256 ; contractions of,
when empty, associated
with hunger sensations,
256-259 ; function of con-
tractions of empty, 263-
264.

Strength : feats of, related to
great emotion, 217-218,
229.

Sugar: in blood, 66, Y3; in
urine, 69-76; relation of
adrenal glands to, in blood,
77; increase of, in blood,
does not hasten clotting,
159, 170; utility of, when
increased in blood, 188-
193; a source of muscular
energy, 191-193; a means
of increasing muscular effi-
ciency, 192-193; use of, in
body, not checked by adre-
nin, 197-199.

Swallowing: inhibits hunger
sensation, 254.

Sweating : value of, in emo-
tion and pain, 203.

"Sympathetic" autonomic di-
vision: extensive distribu-
tion of neurones of, 26;
arranged for diffuse ac-
tion, 28; antagonistic to
cranial and sacral di-
visions, 34-36; active in
pain and strong emotion.

36; emotions expressed in,
opposed to those expressed
in cranial and sacral di-
visions, 268-272 ; domi-
nance of, temporary, 273.

Threshold stimulus : as meas-
ure of irritability. 111;
method of determining,
111-114'; increased in fa-
tigue, 114-117, 120; when
increased, slowly restored
by rest, 117-118, and quick-
ly restored by adrenin,
119-123.

Trial by battle : feats of en-

• durance in, 226.

Vagus nerves: severance of,
does not abolish appetite,
240-241, and does not abol-
ish hunger contractions of
the stomach, 261.

Viscera: similar changes in,
in various strong emotions,
275-279; changes in, not
distinctive for emotions,
280-281.

Vomiting: in consequence of
pain, 19.

Warfare : as an expression of
strong emotions, 286 ; phys-
ical and moral values
claimed for, 287; barbari-
ties of, and opposition to,
289-290; moral substitutes
for, 292-293; physical sub-
stitutes for, 293-297; con-
trast between ancient and
modern, 294-295.

Witnesses : stimulating in-
fluence of, 227.

Work: effect of, on neuro-
muscular irritability, 117;
done with use of car-
bonaceous material, 190-
193.

(1)