Bodily changes in pain, hunger, fear, and rage

by Walter B. Cannon

[41] Macleod: Diabetes, etc., p. 184.

[42] Zuntz: Loc. cit., p. 854.

CHAPTER XII

THE ENERGIZING INFLUENCE OF EMOTIONAL EXCITEMENT

The close relation between emotion and muscular action has long been perceived. As Sherrington[1] has pointed out, “Emotion ‘moves’ us, hence the word itself. If developed in intensity, it impels toward vigorous movement. Every vigorous movement of the body ... involves also the less noticeable coöperation of the viscera, especially 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 researches here reported have revealed a number of unsuspected ways in which muscular action is made more efficient 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 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 muscular fatigue; the mobilizing of energy-giving sugar in the circulation—every one of these visceral changes is directly serviceable in making the organism more effective in the violent display of energy which fear or rage or pain may involve.

“Reservoirs 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 excessively jaded will sometimes invent imaginary offences and put himself into a passion, unconsciously for the sake of reinvigorating himself; and,” Darwin[2] 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[3] cites the instance 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 exhibited in times of stress were dealt with from the psychological point of view by William James[4] 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.

[*] 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, “but the coyote did not, for he was angry and did not feel fatigue.”

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 supplies provided then for muscular contraction, and a special secretion for avoiding or abolishing the depressive influences of fatigue. Tremors, muscular twitchings, the assumption of characteristic attitudes, all indicate that there is an immensely augmented activity of the nervous system—an activity that discharges powerfully even into parts not directly concerned in struggle, as, for example, 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 common means of judging the nature of the experience through which the organism is passing. This “pattern” response of the nervous system to an emotion-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 because of accumulating waste. Under such circumstances of excitement the performance of extraordinary feats of strength or endurance is natural enough.[*]

[*] If individual neurones obey the law of either supreme action 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 resulting manifestation of strength.