Nerves And Nervousness
Nerves, nervous and nervousness are terms which should be used less frequently and less carelessly. "My nerves are on edge" or "I am a nervous wreck" are picturesque expressions devoid of any meaning and which convey a very inaccurate picture of what is taking place in the organism.
To the layman, nerves are just nerves; the nerve which a dentist "kills" and the nerve which makes our heart palpitate are to him identical things.
In reality there are in the human body two nervous systems whose appearance, colour, make up, distribution and functions are as different as night is from day.
There is the sensori-motor system, or the system of nerves which bring to the brain the information about the condition of the various parts of the body and about the way in which those parts are affected by the environment: the nerves which tell us what the eye "sees," what the mouth "tastes," what the nose "smells," whether the water in which we poke our toe is cold or hot, whether the apple we hold is hard or soft.
That system also transmits from the brain to the various muscles definite orders based upon the information received. Motor nerves open or close our eyes, cause us to chew or spit out certain kinds of food, to extend our arm toward a desirable object or withdraw it from a dangerous object, etc.
The sensori-motor nerves are white fibres enveloped in a fatty sheath interrupted at intervals by nodes.
Besides this system there is another nervous system for which various names are being used, such as the vegetative system, the sympathetic system or the autonomic system. These nerves are white fibres covered by a very thin membrane instead of a thick sheath and presenting a more regular appearance owing to the absence of nodes.
Instead of issuing directly from the spinal column as the sensori-motor nerves do, the autonomic nerves, with the exception of the vagus which has its root in the brain, take their roots in a column of ganglia located in front of the vertebrae.
Although this system disintegrates soon after death, for it is poorly protected and its ganglia lie close to tissues which putrefy readily (nasal mucous membrane, buccal cavity and intestinal canal), it is older than the sensori-motor system and it is fully developed at birth.
The autonomic system supplies the internal organs of the body, tear glands, sweat glands, salivary glands, hair roots, lungs, heart, stomach, liver, intestine, adrenal glands, bladder, rectum and genitals. It carries motor impulses, but scientists are not agreed as to whether it carries sensations. It also controls in part the movements of the pupil.
The autonomic system is divided up into two sub-systems which we shall designate as the craniosacral division or end division and the thoracicolumbar division, or sympathetic division or middle division.
The two divisions are absolutely antagonistic in action. For instance the cranio-sacral contracts the pupil, the sympathetic dilates it, the cranio-sacral division slows down the heart action, the sympathetic division accelerates it.
The craniosacral division promotes all the activities which build up the individual and assure the continuance of the race.
The sympathetic division which extends from the neck to the upper sacral region, decreases or stops all those activities in emergencies and releases safety devices.
For instance the cranio-sacral division causes saliva to flow, which helps the disintegration of food in the mouth; it causes the stomach glands to secrete gastric juice and the stomach to contract regularly and vigorously, which activates the digestion and speeds the digested food on its way into the intestine; it contracts the intestine and hence assists the elimination of waste matter; it holds the rectum and bladder openings closed until the proper accumulation of feces or urine makes voiding necessary; it regulates the heart beats, prevents the pupil from admitting too much light and focuses it so that it throws a clear image on the retina; finally it fills the exterior genitals with blood and enables them to perform their specific functions.
The sympathetic division, on the contrary, stops the flow of saliva and of gastric juice, stops the contractions of the stomach or reverses their direction, so that food may be regurgitated into the oesophagus and, at times, vomited; it speeds the heart action; at times, it voids suddenly the bladder and bowels; releases into the blood stream a flow of adrenin which contracts the arteries and a flow of sugar from the liver which supplies the body with extra fuel; stops all genital functions; causes the pupil to dilate, thus giving the eye a staring glare; bristles the hair, causing goose flesh, etc.
One can see at once how all the activities of the sympathetic protect the organism either directly, by initiating necessary activities, or indirectly, by inhibiting certain activities which are not necessary in emergencies.
When the organism is in danger, that is, must resort to fight or flight, nutrition and sex activities should cease. Not only should. they cease because the organism in danger cannot attend to them properly, but also because they deflect toward their specific organs a certain amount of blood which is needed elsewhere for defensive purposes. Hence the dry mouth, the arrested gastric action, the impotence induced by fear.
As the blood must circulate freely in the endangered organism and absorb as much oxygen as possible, the heart beats are increased and so is the rate of respiration. As a larger amount of energy has to be expended, the glycogen (sugar) stored up in the liver must be released into the blood stream, after the fashion of a motorist who "steps on the gas" in order to climb ,a steep hill; if a wound be sustained, adrenin is mixed with the blood causing it to coagulate more quickly and close the wound; finally the hair must be raised, affording to certain animals, such as cats and dogs, a certain amount of protection against teeth and claws and surrounding the body, in the case of porcupines and hedge-hogs, with an impassable barrier of sharp daggers.
The sudden voiding of the bowels and bladder caused by fright is another emergency measure taken by the sympathetic division. Empty bowels and an empty bladder present a more favourable condition in the case of deep abdominal injuries, while the same organs, if full, might cause complications.
The activities of the sympathetic division correspond to what we may call the safety urge, while the cranial division which promotes nutrition and assimilation would correspond to the food-ego-power urge and the sacral division to the sex urge.
We may notice that the nerves of ego and sex work in unison.
The two divisions of the autonomic system are not always balanced with perfect accuracy and one of them is bound to predominate. This will enable us to distinguish roughly three "nervous" types.
The type in which the positive activities which build up the individual and further the continuance of the race are not hampered by the negative activities of the sympathetic except in emergencies.
This is the type we may justly consider as normal.
The second type is one in which the positive activities are so strong that they cannot be checked in emergencies by the safety nerves. When the personality is overwhelmed by the cranio-sacral division, that is by the ego and sex urges, the individual is unadaptive and unsocial. Criminal, gluttonous, obscene imbeciles belong to that type for which the terms vagotonic has been suggested.
In the third type, or sympathicotonic type,, the sympathetic division functions in and out of season, flashing danger signals when there is no danger and holding back the natural cravings for nutrition, self-expression, acquisition, power, reproduction, etc. Neurotics suffering from anxiety, obsessions, phobias, nervous indigestion, psychic impotence, etc., belong to this type.
A very simple test has been devised to determine to what type a subject belongs. It is known as the Aschner test. It is based on the fact that the ends of both divisions, the cranial and the sympathetic divisions, can be reached and stimulated by pressure on the pupil.
The cranial division increases the heart beats and the sympathetic division decreases them. By applying the same stimulation to both divisions, the one which is more powerful will react more easily than the other. If after pressing on the eyeballs for half a minute, the initial pulse, let us say 90, has been reduced to about 80, the patient is probably normal. If the pulse rate has been decreased by more than 10 or 12 beats, the patient is vagotonic, and if the pulse rate has remained unchanged or has been increased the patient is sympathicotonic.
A study of the autonomic system enables us to visualize complexes as defensive actions of the sympathetic division or safety urge which were initiated at some past time, generally in infancy when stimuli are likely to produce the deepest impression and which continue to be performed when no actual danger has to be warded off, or in emergencies which are not real emergencies but appear as such owing to wrong associations.
A child, frightened unwisely, may all his life show defence and fear reactions, which means that the nerves of his sympathetic division will constantly interfere with his digestion, his heart action, his intestinal peristalsis, his sex life.
A child hurt by a doctor with a black beard, a classical case in psychoanalytic literature, unconsciously associated in later life all men with black beards with the man who hurt him once and when meeting such a man suffered from arterial tension connected with fright.
Experiments made on dogs illustrate well the mechanism of association.
A dog was submitted to a delicate operation whereby the gastric juice secreted by his stomach would run into a graduated tube. For several days a bell was rung every time the dog was given food. To the sight of food there always corresponded a flow of gastric juice. One day the bell was rung but no food was offered to the animal. In spite of the absence of food, gastric juice began to trickle into the test tube. A "bell association" had been created in the dog's organism. In other words, as for several days the sound of a bell had been connected with the sight and taste of food, his autonomic nerves promoted the flow of gastric juice as soon as the bell rang.
A study of the autonomic activities sheds a new light upon many actions which at the present day are considered as voluntary and subjected to criticism or praised from a purely ethical point of view based upon the distinction between body and mind.
A sixty candle power bulb should not be criticized for carrying an amount of electrical power inferior to that which can flow through a hundred candle bulb.
A coward is not a coward because he wishes to run away, but because his sympathetic nerves promoting flight are especially sensitive to fright stimuli which in other men would produce no reaction or a reaction of fight. As Jacques Loeb would put it, a coward runs in the direction where his legs carry him. As the unscientific layman would express it, the coward "loses his nerve" or "is all nerves" or "cannot control his nerves."
Punishing a coward and insulting him will not make him a brave man. It may compel him to pretend fora time that he is brave, after which he may succumb to shell-shock when his cravings for safety, long repressed, assert themselves violently and abnormally.
But he need not remain a coward and can be trained to master his fear by analyzing it and by disintegrating the absurd associations which set his organism in flight when no dangerous emergency exists.
A coward with a well developed intelligence can be made, through education, as indifferent to certain fear stimuli as other people can be made in-different to some apparently alarming symptoms of sickness.
For example: any one taking the typhoid vaccine will after the first injection feel dreadfully sick. He will develop violent fever, suffer from headaches, thirst, palpitations, nausea, he will feel very weak, etc., in other words, he will, within twenty-four hours, experience most of the symptoms of the disease against which the vaccine is to protect him. Duly warned by a physician, the patient will not worry over those disturbances which are "expected," as suppuration is expected after vaccination for smallpox.
The patient knows what is causing his malaise and what its duration shall be. While he could not very well "enjoy" the situation, he resigns him-self to it as to something temporary and unavoidable.
On the other hand, should a careless physician fail to warn the patient of the effects of the first hypodermic dose, the patient would add to the unpleasant condition induced by the vaccine a deep worry, a fear of possible complications and perhaps devise unnecessary plans for emergency action, thereby affecting his heart beats, his gastric and intestinal activities and so on.
Knowing to what type he belongs is as necessary for a human being as knowing, for instance, whether one of his legs is shorter than the other. A cripple in ignorance of the disparity of his legs, would gather the impression that the road he was travelling was strewn with ruts and obstructions. The longer leg would seemingly encounter number-less obstacles while the shorter would be constantly descending into holes.
The man with a vagotonic tendency whose ego and sex urges are apt to disregard the warnings of his safety urge and the man with as ympathicotonic tendency whose sympthetic division is constantly raising the danger flag are bound to have very distorted impressions of their mental states and of their environment.
Knowing themselves better, they can discount considerably such deceptive impressions and there-by correct their behaviour.
Those called upon to judge them can also by understanding better their nervous mechanism, help them to conform to standard conduct.
Even the perfectly normal man can derive much comfort from knowing positively that he is normal at ,times when, in a crisis or emergency, he might conceive doubts as to his condition. A knowledge of the functioning of one's autonomic system is at all times of great assistance in remaining normal.
That knowledge also enables one to adopt or to avoid for scientific, that is, plausible and compelling reasons, certain forms of behaviour.
The following observation made on dogs by Pavlof teaches a lesson which should be remembered by every human being.
A dog submitted to the surgical operation I mentioned previously secreted some seventy cubic centimetres of gastric juice when fed a certain amount of meat. One day, a cat was brought into the laboratory while he was partaking of his meal and aroused his anger. On that occasion, the amount of gastric juice which flowed into the test tube was just one tenth that accompanying a peaceful undisturbed meal. Anger and fear had raised the danger signal in his organism and prepared the dog for fight or flight, but not for the enjoyment of a meal.
A quarrel at the dinner table affects human beings as the sight of a cat affected our dog. Their flow of gastric juice is stopped or considerably reduced and whatever food they take into their stomachs would linger in that organ much longer than it should normally. The result will be some form of "nervous indigestion," perhaps nausea and in extreme cases, vomiting.
Observations of a similar order were made on a small boy suffering from a gastric fistula which allowed gastric juice to flow out of his body. When the boy chewed pleasant food, the flow was copious, whereas the chewing of some unpleasant or in-different substance was not followed by any secretion.
The flow of gastric juice is not induced solely, as many people think, by the pleasant taste of food.
The mere sight of appetizing aliments is sufficient to start the digestive fluids.
Hence, a meal served in an attractive dining room, on clean linen, in dainty dishes, with flowers on the table, in a peaceful, soothing atmosphere, to the tune of caressing, unemotional music, is likely to be digested more easily than food served in slovenly, noisy surroundings.
This applies to almost every experience in life.
Pleasant memories of gratifying happenings create durable associations, like the food-bell association which had such an appetizing effect on Pavlof's dog. Unpleasant memories produce perhaps even more lasting effects of the opposite character and are responsible for a thousand "nervous" ills.
Every psychological theory will have to be revised according to the rather recent findings of scientists touching the autonomic functions. While space does not allow us to dwell at length on that aspect of the subject, we may say a few words on the new interpretation of will-power which can be based upon the study of the autonomic nervous system.
The vagotonic, whose "animal" activities can hardly be checked by a weaker sympathetic division, is called. "a creature of instinct," "led by his cravings," "subservient to his lower nature," "lacking in will-power," etc.
He whose sympathetic system acts in all emergencies and in emergencies only, that is, does not create absurd, unconscious reasons for illogical behaviour, is credited with a great amount of will-power.
He whose sympathetic system acts in and out of season, overpowering his ego and sex urges, creating emergencies and raising obstacles, is constantly "nervous," vacillating, considering one course and then another, "unable to make up his mind."
Education undertaken by a trained psychologist, not by a disciplinarian, may alter the first type by developing in his sympathetic division a fear of the absolute privation which may be the consequence of vagotonic indulgence.
The third type also can be trained to recognize a true emergency from an imaginary one and to gauge accurately the size of the obstacles rising in his path.
Neither type should be dealt with by jailers or judges. Neither should be held responsible for behaviour due to weakness or self-deception. Both should, if their conduct is socially intolerable, be restrained and educated. Those whose nervous
system appears inadaptable should remain the wards of the state and be considered as victims of organic maladjustment for which they are in no wise responsible.