The Origin and Nature of Emotions - George W. Crile (books to read to improve english txt) 📗

class="calibre1">While this motor preparation is going on, the entire digestive tract is inhibited. It thus becomes clear why an emotion is more harmful than action.

 

Any agency that can sufficiently inspire faith,—dispel worry,—

whether that agency be mystical, human, or divine, will at once stop the body-wide stimulations and inhibitions which cause lesions which are as truly physical as is a fracture.

The striking benefits of good luck, success, and happiness; of a change of scene; of hunting and fishing; of optimistic and helpful friends, are at once explained by this hypothesis.

One can also understand the difference between the broken body and spirits of an animal in captivity and its buoyant return to its normal condition when freed.

 

But time will not permit me to follow this tempting lead, which has been introduced for another purpose—the proposal of a remedy.

 

Worries either are or are not groundless. Of those that have a basis, many are exaggerated. It has occurred to me to utilize as an antidote an appeal to the same great law that originally excited the instinctive involuntary reaction known as fear—

the law of self-preservation.

 

I have found that if an intelligent patient who is suffering from fear can be made to see so plainly as to become firmly convinced that his brain, his various organs, indeed his whole being, could be physically damaged by fear, that this same instinct of self-preservation will, to the extent of his conviction, banish fear.

It is hurling a threatened active militant danger, whose injurious influences are both certain and known, against an uncertain, perhaps a fancied, one. In other words, fear itself is an injury which when recognized is instinctively avoided. In a similar manner anger may be softened or banished by an appeal to the stronger self-preserving instinct aroused by the fear of physical damage, such as the physical injury of brain-cells. This playing of one primitive instinct against another is comparable to the effect produced upon two men who are quarreling when a more powerful enemy of both comes threateningly on the scene.

 

The acute fear of a surgical operation may be banished by the use of certain drugs that depress the associational power of the brain and so minimize the effect of the preparations that usually inspire fear.

If, in addition, the entire field of operation is blocked by local anesthesia so that the associational centers are not awakened, the patient will pass through the operation unscathed.

 

The phylogenetic origin of fear is injury, hence injury and fear cause the same phenomena. In their quality and in their phenomena psychic shock and traumatic shock are the same. The perception of danger by the special senses in the sound of the opening gun of a battle, or in the sight of a venomous snake, is phylogenetically the same and causes the same effects upon the entire body as an operation under anesthesia or a physical combat in that each drives the motor mechanism.

The use of local anesthetics in the operative field prevents nerve-currents from the seat of injury from reaching the brain and there integrating the entire body for a self-defensive struggle. The result, even though a part of the brain is asleep and the muscles paralyzed, is the same as that produced by the interception of the terrifying sound of the gun, or of the sight of the dangerous reptile, since the stimulation of the motor mechanism is prevented.

 

By both the positive and the negative evidence we are forced to believe that the emotions are primitive instinctive reactions which represent ancestral acts; and that they therefore utilize the complicated motor mechanism which has been developed by the forces of evolution as that best adapted to fit the individual for his struggle with his environment or for procreation.

 

The mechanism by which the motor acts are performed and the mechanism by which the emotions are expressed are one and the same.

These acts in their infinite complexity are suggested by association—

phylogenetic association. When our progenitors came in contact with any exciting element in their environment, action ensued then and there. There was much action—little restraint or emotion.

Civilized man is really in auto-captivity. He is subjected to innumerable stimulations, but custom and convention frequently prevent physical action. When these stimulations are sufficiently strong but no action ensues, the reaction constitutes an emotion.

A phylogenetic fight is anger; a phylogenetic flight is fear; a phylogenetic copulation is sexual love, and so one finds in this conception an underlying principle which may be the key to an understanding of the emotions and of certain diseases.

 

PAIN, LAUGHTER, AND CRYING[*]

 

[*] Address delivered before the John Ashhurst, Jr.. Surgical Society of the University of Pennsylvania, May 3, 1912.

PAIN

Pain, like other phenomena, was probably evolved for a particular purpose—

surely for the good of the individual; like fear and worry, it frequently is injurious. What then may be its purpose?

 

We postulate that pain is one of the phenomena which result from a stimulation to motor action. When a barefoot boy steps on a sharp stone it is important that the injuring contact be released as quickly as possible; and therefore physical injury pain results and impels the required action. Anemia of the soft parts at the points of pressure results from prolonged sitting or lying in one position, and as a result pain compels a muscular action that shifts the damaging pressure—this is the pain of anemia; when the rays of the blazing sun shine directly upon the retina, pain immediately causes a protective muscular action—the lid is closed, the head turns away—this is light pain; when standing too close to a blazing fire the excessive heat causes a pain which results in the protective muscular action of moving away—this is heat pain; when the urinary bladder is acutely overdistended the resultant pain induces voluntary as well as involuntary muscular contraction—

this is evacuation pain; associated with defecation is a characteristic warning pain, and an active pain which induces the required muscular action—this, like the pain accompanying micturition, is an evacuation pain; in obstruction of the urinary passages and of the large and the small intestine the pain is exaggerated, as is the accompanying muscular contraction—this is a pathologic evacuation pain; when the fetus reaches full term and labor is to begin, it is heralded by pain which is associated with rhythmic contractions of the uterine muscle; later, many other muscles take part in the birth and pain is associated with all these muscular contractions—these are labor pains; when a foreign body, be it ever so small, falls upon the conjunctiva or cornea there results what is perhaps the acutest pain known, and quick and active muscular action follows—this is special contact pain. Special pain receptors are placed in certain parts of the nose, the pharynx, and the larynx, the stimulation of which causes special motor acts, such as sneezing, hawking, coughing. Curiously vague pains are associated with the protective motor act of vomiting and with the sexual motor acts—these may be termed nausea pains and pleasure pains.

We now see, therefore, that against the injurious physical contacts of environment, against heat and cold, against damaging sunlight, against local anemia when resting or sleeping, the body is protected by virtue of the muscular action which results from pain.

Then, too, for the emptying of the pregnant uterus, for the evacuation of the intestine and of the urinary bladder as normal acts, and for the overcoming of obstructions in these tracts, pain compels the required muscular actions, For passing gall-stones and urinary calculi, urgent motor stimuli are awakened by pain.

For each of these diversified pains the consequent muscular action is specific in type, distribution, and intensity. This statement is so commonplace that we are apt to miss the significance and the wonder of it. It is probable that every nerve-ending in the skin and every type of stimulation represents a separate motor pattern, the adequate stimulation of which causes always the same response.

 

Let us pass on to the discussion of another and perhaps even more interesting type of pain, that associated with infection.

Not all kinds of infection are painful; and in those infections that may be associated with pain there is pain only when certain regions of the body are involved. Among the infections that are not associated with pain are scarlet fever, typhoid fever, measles, malaria, whooping-cough, typhus fever, and syphilis in its early stages.

The infections that are usually, though not always, associated with pain are the pyogenic infections. The pyogenic infections and the exanthemata constitute the great majority of infections and are the basis of the discussion which follows.

 

I will state one of my principal conclusions first, _i.

e_., that the only types of infection that are associated with pain are those in which the infection may be spread by muscular action or those in which the fixation of parts by continued muscular rigidity is an advantage; and, further, as a striking corollary, that the type of infection that may cause muscular action when it attacks one region of the body may cause no such action when it attacks another region.

 

The primary, and perhaps the most striking, difference between the painless exanthemata and the painful pyogenic infections is that in the case of the exanthemata the protective response of the body is a chemical one,—the formation of antibodies in the blood, which usually produce permanent immunity,—while the response to the pyogenic infections is largely phagocytic. In the pyogenic infections, in order to protect the remainder of the body, which, of course, enjoys no immunity, every possible barrier against the spread of the infection is thrown about the local point of infection.

How are these barriers formed? First, lymph is poured out, then the part is fixed by the continuous contraction of the neighboring muscles and by the inhibition of those muscles that, in the course of their ordinary function, would by their contractions spread the infection.

Wherever there is protective muscular rigidity there is also pain.

On the other hand, in pyogenic infections in the substance of the liver, in the substance of the kidney, within the brain, in the retroperitoneal space, in the lobes of the lung, in the chambers of the heart and in the blood-vessels of the chest and the abdomen, in all locations in which muscular contractions can in no way assist in localizing the disease, pyogenic infections produce no muscular rigidity and no pain. Apparently, therefore, only those infections are painful which are associated with a protective muscular contraction.

This explains why tuberculosis of the hip is painful, while tuberculosis of the lung is painless.

 

There is a third type of pain which modifies muscular action in a curious way. We have already stated that local pain serves an adaptive purpose. In this light let us now consider headache.

Headache is one of the commonest initiatory symptoms of the various infections, especially of those infections which are accompanied by no local pain and by no local muscular action.

In peritonitis, cholecystitis, pleurisy, arthritis, appendicitis, salpingitis, childbirth, in obstructions of the intestinal and the genito-urinary tract, in short, in those acute processes in which the local symptoms are powerful enough to govern the individual as a whole,—to make him lie down and keep quiet, refuse food and possibly reject what is already in the stomach,—

in all these conditions there is rarely a headache, but in the diseases in which local pain is absent, such as the exanthemata, typhoid fever, and autointoxication, which have no dominating local disturbances to act as policemen to put the individual to bed and to make him refuse food that he may be in the most favorable position to combat the oncoming disease, in such cases in which these masterful and beneficent local influences are absent we postulate that headache has been evolved to