TIC CONVULSIF This term is applied to a peculiar disease which has been especially studied by two of Charcot's students, Gilles de la Tourette and G. Guinon, and is therefore often called after these two authors. The disturbance manifests itself in a variety of stereotyped muscular movements, recurring at regular intervals and always identical in character, in the same individual. The course is chronic.
A certain external resemblance which the disease exbibits to chorea minor induced Weir Mitchell to speak of a "habit chorea," but this term should be avoided because the disease has nothing whatever to do with chorea. The term "coordinating memory convulsions," selected by Friedreich, more correctly describes the nature of the malady, as will presently appear.
Facial tic is the simplest form of the disease. It eonsists of short, clonic contractions or twitchings in one, or rarely both sides of the face. As a rule it does not affect the entire distribution of the facial nerve, but rather resembles certain isolated movements of facial expression, such as blinking, wrinkling of the forehead, raising the eyebrows, showing the teeth, drawing up the corners of the mouth as in laughing, etc., repeated at short intervals.
The twitchings in the facial muscles may be isolated or may be combined with other tic movements.
In rarer cases they are the expression of a circumscribed cortical lesion and are then to be regarded as abortive forms of eortical epilepsy, or of a reflex irritation of the facial through the trigeminal—tic douloureux.
As a rule, however, the underlying condition is a psychomotor functional disturbance similar to that which exists in generalized tic.
The tic movements, as has been stated, are of all kinds, shaking, rotating, or nodding of the head, rotation or jerking of one or both should ers, jerking movements of the arms or legs, grasping, stamping, hopping, jumping, climbing, and bicycle riding movements, of every conceivable variety. Some patients habitually pick their noses or their chins, and in almost every case tic movements are observed in the face.
The movements resemble those of chorea, but are as a rule more rapid and more forcible and, when first seen, give the observer more the impression of a conscious or volitional, purposive movement. For this reason the term corirdinated tic is used. The movements, however, are characterized by absence of purpose, by their intensity and stereo typic repetition at variable intervals, or sometimes in series.
Frequently the muscles of articulation, phonation and respiration are also involved, giving rise to the production of inarticulate choking, clacking, or other animal-like sounds, spitting (like a cat), barking, and similar noises.
Sometimes there is an uncontrollable impulse to utter obscene words (koprolalia,), although this appears to be rare in children; or meaningless concatenation of syllables, or a tendency to repeat over and over again (stereotypically) words accidentally overheard (echolalia).
When the patient is completely absorbed in some occupation, or if his attention can be distracted, the tic movements diminish in intensity or cease altogether, as during sleep. Excitement and the consciousness of being observed increase the movements. By a strong effort of the will tic can be controlled for a thne, but at the expense of a painful sense of coercion.
Psychic factors are the most prominent in the etiology, and the disease ts undoubtedly closely related to hysteria.
Many cmes must be regarded as hysterical, particularly those which exhibit dancing, jumping, stamping and other similar movements, which have received the special name of saltatory reflex convulsions (Bam berger). Its close connection with astasia and abasia, which have been described among the hysterical symptoms is obvious. The knowledge of this pathogenic relationship is of great value from a therapeutic stand point, because the above conditions are susceptible of rapid cure.