Two types of tremors come to us for treatment: those that are quite involuntary and occur when muscles are at rest, and those that are associated with voluntary movements. The most common type of involuntary tremor is that seen in paralysis agitans to which a special chapter is devoted. After this, though coming for treatment much less frequently, is senile tremor which may, however, also be increased by voluntary movement. The tremors associated with voluntary movements are spoken of as intentional tremors. They may occur as the result of organic disease of the nervous system and the most characteristic type is that seen in multiple sclerosis. They are more frequent, however, with functional diseases of the nervous system and with emotional disturbances of various kinds. They are especially frequent as the result of dreads. Usually the idea of tremor is associated only with the head and the hands. Tremors may occur in other parts of the body, however, and tremors of the legs are particularly important. A familiar type is the tremor and unsteadiness of the legs which occur as a consequence of the dread of heights when a person unused to such situation attempts to walk across a narrow path a great distance above the ground.

Senile Tremor.—The most common of the involuntary tremors is that associated with old age. It develops in practically all very old people, but it comes to some who are comparatively young. Its occurrence at the age of fifty-five usually gives the sufferer a severe shock which is emphasized by the attitude of mind of friends toward the affection. They seem to be always sure that it is the index of rapidly advancing age and that it is practically a signal of approaching dissolution. As a matter of fact, when unassociated with gross pathological lesions, the senile tremor has no such significance. When associated with definite lesions it is the prognosis of the special condition and not any supposed significance of this particular symptom of tremor that expresses the genuine outlook in the case. Many people who live to a very old age develop tremor before they are threescore. Most of those who live to be eighty or more have some tremor that develops about or just after the age of seventy.

Significance.—Senile tremor is supposed to be due to, and in most cases probably is the result of, an overgrowth of connective tissue in the central nervous system which disturbs the ordinary conduction of nerve impulses, rendering them wavering and uncertain. This seems to indicate that it will not be long before the advancement of this sclerotic process will make serious inroads on the vigor of the individual. As a matter of repeated observation, however, the ordinary involuntary tremor of old people may last twenty years.

Reassurance.—The main principle in the treatment of tremors of the old is to make the patients realize that the symptom has no such bad prognosis as is usually attributed to it. Of course, they will find this out for themselves after a few years, but what they need is assurance at the beginning lest during the period of depression consequent upon the conclusion that the end is not far {581} off, which seems to be forced on them by their fears and the foolish sympathy of friends, their resistive vitality should be so lowered as to permit the invasion of some serious disease. In spite of apprehensions on the part of themselves and friends, tremor is rather a good sign than a bad one. It indicates the formation of connective tissue in the central nervous system, but this is always a slow process and is usually quite benign. As a matter of fact, most sclerotic processes are so chronic as to be compensatory in their action for many other degenerations. Those in whom tremor develops early often seem to be better protected against rupture of cerebral arteries, as if the growth of connective tissue was a conservative process here also. Information of this kind helps patients not to borrow trouble because of their condition.

Intention Tremors.—The tremors that occur in association with voluntary movements are often very troublesome and may be difficult to manage. The worst cases are entirely functional. They are typical neuroses and often develop as a consequence of some serious crisis through which the nervous system has passed. In older people they sometimes pass over into paralysis agitans or a close simulant of that affection. The incident of the Texas sheriff and the Indian related in the chapter on Paralysis Agitans illustrates how these tremors may be induced.

Tremors from Fright.—Frequently the tremors have no direct connection with any action, though they may be the result of fright. A little girl bitten by a dog and much shocked may, for some time afterwards, be quite unable to stand when she sees a dog on the street, so disturbing is the tremor that comes over her. Tremors of the same kind have been connected with horses after the patient had been run down in the street, and, in one case that I saw even when the patient was only thrown out of a carriage during a runaway. Occasionally fright by a burglar may cause a distinct tremulousness that supervenes whenever the patient thereafter is wakened suddenly at night.

Influence of Dread.—Tremors of all kinds can be made worse by the dread of them. In the chapter on Dreads we discuss the disturbance of function by dreads and especially the tendency to exaggeration of pathological conditions of any kind when the patient's mind becomes concentrated on it. Steadiness in any position is due to a nice balancing of extensor and flexor muscles requiring the sending down of a continuous stream of impulses. The equilibrium is attained and maintained in spite of the fact that, as a rule, the flexor muscles are stronger than the extensors and better situated to exert their mechanical force. If anything happens to disturb this balance even to a slight degree, the mind becomes attracted to it and there is a corresponding result as in stuttering, or other complex function when surveillance is too great. It is important to remember this at the beginning of all cases of tremor, for the patient nearly always exaggerates his tremor by attention to it and can be made so much better by reassurance and diversion of mind that he is much encouraged and his general health usually improves, making him feel, even though his affection is organic, that he is being cured.

Tremors may occur in connection with almost any set of actions requiring special co-ordination of muscles, but they are especially likely to occur when a feeling of dread disturbs the control over muscles. A typical example of this is noted in shaving. There are many men who cannot shave without trembling so as to cut themselves. The feeling that they have a sharp instrument in their {582} hand with which they may cut themselves sets up the tremor. There are others who cannot shave because they dread that while using the instrument over the important organs of the neck, and especially the blood vessels, they may be tempted to cut their throats. This is, of course, purely a dread and not a tremor. Some men find both the dread and the tremor much worse at times when they are tired and worried, and can shave very well at other times. Some men can shave very well when they are not under observation, but if anyone is looking at them they tremble and cut themselves. The safety razor usually does away with these troubles, large or small, but if it should happen that by particularly inexpert use they cut themselves even with a safety razor, especially in the throat region, the old dread and tremor reassert themselves and shaving becomes almost as difficult as before.

Self-consciousness.—Almost any position or action in which a man feels himself under observation may cause one of these tremors. As a consequence this particular set of actions may become the source of so much discomfort as to produce an intense sense of fatigue. It may, indeed, become quite impossible of accomplishment. Some teachers cannot do demonstrating work on a blackboard before a large unfamiliar class, at least not without serious efforts to control themselves, though they may be facile demonstrators before a small class. I have known men, however, who practically could not do blackboard work at all because of nervousness. Their writing went all askew and very often their thoughts would not follow one another in such order as to make demonstrations possible. Sometimes they were good talkers, so long as they did not turn their backs to the class and feel the eyes of all on them. The same thing is true of such religious services as Mass in the Catholic Church, where some of the clergymen have this feeling. I know of priests who have not said Mass publicly for years and others who can only say it in a small chapel before a few people because of the intense discomfort of the fatigue caused by this state of mind.

Stage Fright.—It is not alone the hands and the arms that tremors are likely to affect, for they may also occur in the legs. A typical and familiar case is the tremor that occurs upon the first appearance before large audiences of orators or actors or clergymen. Owing to excitement, they are unable to make flexor and extensor muscles exactly balance each other and the consequence is a tremulous movement that may be complicated by some swaying. Some people never lose this in spite of long experience in public appearance. Young people may have it upon being introduced to persons of whom they think a great deal. This passes off with years, as a rule, but in some it persists, and any excitement causes tremor of the legs and swaying movements. The effort to control this is often severe and causes intense fatigue.

Any set of movements requiring even slight co-ordination of muscles may be the subject of disturbance by a tremor. Since the writing of the book on Pastoral Medicine, a text-book of medical information meant to be of assistance to clergymen, [Footnote 43] I have had some rather interesting tremors associated with the performance of clerical duties brought to my attention. One of these is a trembling of the legs which makes standing at a high altar almost impossible. Another troublesome tremor is that associated with the giving of communion. {583} Most priests find no difficulty in the performance of the rite. Some of them are much worried and anxious about it, however, and develop a slight tremor. Others become so nervous in performing the ceremony that they cannot succeed in placing the Host on the tongue of the communicant without certain false movements. These may cause them to touch the lips or the cheeks of the recipient and after this has happened a few times the giving of communion becomes practically impossible for them. Occasionally the men thus affected have no other nervous symptoms and often they are very intelligent, strong-minded men.

[Footnote 43: O'Malley and Walsh, "Pastoral Medicine." Longmans, 1906.]

The General Health.—Tremor patients always complain more of this symptom when they are in a run-down condition. One of them is a wealthy merchant who, when he can be persuaded to take a vacation, comes back with nearly all the manifestations of his tremor latent or, at least, well under control. Another is a broker who at the end of a long winter of excitement and worry is at his worst, but who after a vacation in the North Woods is quite well again. Slight symptoms of this kind are not unusual in teachers, especially women, though I have seen them also in men, and are much more complained of at the end of the year when the individuals are in poorer general condition than at any other time. The symptom itself is annoying because of the notice that it attracts, but their dread that it may have some serious significance, indicating the development of a progressive lesion of the central nervous system, constitutes the worst part of their ailment. When the intentional tremor is intermittent and occurs only at times of excitement, or when the patients are under observation, they can be reassured that it is merely neurotic and that no ulterior development is to be anticipated.

Treatment.—The treatment of these conditions consists first in bringing the patient's health up to its normal condition as far as that is possible. Many of the sufferers from tremors are under weight. Whenever they are, a definite, determined effort must be made to bring them up to it. This must be done even though they insist that they have never been heavier and that to be rather underweight is a family trait. In many cases it will be found that this family trait, instead of being due to some inevitable hereditary tendency, is only the result of family habits in the matter of eating. Many of these people do not eat substantial breakfasts. Their tremor, too, is likely to be worse in the early morning than at any other time during the day, unless, of course, they have become overtired during the day, when the tremor will reassert itself with vigor. Most of them are much less disturbed in the afternoon than before. The drug treatment of the affection consists mainly in the use of nux vomica, but, not in the small doses of five or ten drops so often employed, but, according to the size of the individual, beginning with fifteen or twenty minims, thirty or forty drops, and gradually increased to physiological tolerance, when the dose should be set somewhat below that.

Mental Control.—The main treatment must consist, however, in enabling the patient to secure psychic control over himself and his muscles. This is not an easy matter. Most of them are quite discouraged, but their attitude of mind must be changed and the real significance of their affection made clear to them. As a rule, they have either heard or read or been told by a physician that their intentional tremor is significant of a serious pathological lesion of the central nervous system. Some of them have heard of multiple sclerosis {584} and are much disturbed. They must be reassured and it must be made clear to them that their disease is really due to over-consciousness and consequent lack of control. A good deal of reassurance can be given by telling them of patients who suffer from ailments not unlike theirs, showing how multiform the affection is. A man who has trouble with his signature may be told about the man who finds it difficult to drink when under observation, then, as a rule, he will better realize the neurotic character of his affection. With hysterical women this method must be used with care or the story of another patient will act as a suggestion and the physician will subsequently be treated to an exhibition of the symptoms which he has described.

Self-Discipline.—Persistent quiet discipline is the one thing that eventually does any good. When patients are first told of this and are persuaded to attempt it, they make such a determined effort to overcome the affection that they make themselves more conscious of it than before with the result that their tremor and spasmodic movements are emphasized. It is the old story of the man trying to stand so straight that he falls backwards. It must be made clear to them that discipline, to be of any value, must be carried out as much as possible without consciousness of it and with all available artificial aids. The man who has trouble with his signature may be shown that he can overcome much of the tendency to tremor and spasm of the forearm muscles that are at the root of his difficulty by sitting at a higher chair, so that his arm swings free of the table and so that, in Gowers' phrase, if a pen were attached to his elbow it would write the same thing as the pen in his hand. The man who trembles as he drinks may be taught for a time to raise a cup to his lips while resting his elbow on the table and bringing his head well down. Nearly always methods of performing particular actions that require less effort can be found, until the habit of over-consciousness and loss of control is overcome.

Hypnotism and Waking Suggestion.—Occasionally hypnotism is effective in these cases, but there is likely to be a relapse unless there is some discipline before and after its use. Suggestion in the waking state is often very effective. Patients need to be talked to and even though intelligent they need to be reminded at regular intervals for some time that their ailment is merely functional and not organic. Nearly always it will be found that they trace its beginning to some pathological event: occasionally there has been a severe accident, but sometimes only a slight accident seems to them a sufficient explanation. Sometimes it follows an attack of pneumonia, oftener still typhoid fever. In these cases the patients become convinced that this is one of the marks left after the accident or disease and so it is rather hard to persuade them that they can be cured. All such impressions, which act as auto-suggestions for the continuance of their tremor and lack of control, must be combated, otherwise there is very little hope of improvement. The preceding disease is not the direct cause, though the weakness consequent upon it may predispose to the tremor. Overhaste in attempting to resume their occupations before their strength has returned is often the real cause. It is the patient's mind more than his body that needs to be set in order, but this will not be possible unless the physical condition is normal and thorough reassurance can be given.{585}

DISORDERS OF THE PSYCHE