[1] Tics and their treatment. English translation by S. A. K. Wilson. New York, 1907. This book contains an extended bibliography. VIEWS OF THE FRENCH SCHOOL The usual conception of tics, as laid down by Brissaud, Meige and Feindel,[1] may be stated as follows: Tic movements are physiological acts which were originally functional and purposeful in character, but which have become habits, apparently purposeless and meaningless. The motor reaction is the result of some external stimulus or idea (normal or abnormal) or both, which originally was necessary for the production of the tic movement, which latter eventually became habitual and automatic, and, owing to repetition, was executed, even in the absence of the external stimulus or idea, without apparent purpose or meaning. At first but little more than purposive habit movements, they finally became irrepressible acts which sought for expression, which were but little under the control of the will, which occurred in attacks varying in frequency, duration and severity, which decreased under distraction and generally ceased during sleep, which were increased in frequency and duration and severity by fatigue, emotional upset, mental unrest, conflict and strain, while the lack of inhibition and will power, the lack of self-control was the dominant mental state, leading to feelings of insufficiency, doubt, indecision and incapacity, and making the ground work for the psychasthenic reactions in the form of morbid impulses and obsessions, and for the hysterical, so-called neurasthenic and other morbid psychic trends. The inherent or acquired neuropathic and psychopathic state is the basic condition which prepares the subsoil. From a consideration of the motor symptom we may say that it is but a pathological habit, which, however, is apt to lead to the tendency toward or generation of an increasing number of such pathological habits. Characteristic of tics we may mention their being conscious before and after but not during their execution, their being disordered functional acts, their impetuous, irresistible demand for execution, the antecedent desire, and the subsequent satisfaction. The etiology of tics, as laid down by Meige and Feindel, may be summed up by stating that they occur most frequently in young subjects, less frequently in savages and animals than in the civilized, there is a psychic predisposition based on heredity (of a similar or dissimilar neuropathy or psychopathy) upon which Charcot laid great stress, imitation (especially in the young) plays a role, as also brain fatigue (emotion, mental upset and worry) and indolence, with the frequent exciting cause of an external or internal stimulus or an idea, which is the explanation of the origin, source, situation and form of the tic or tics present in any particular case.