To establish the diagnosis of mental torticollis, the existence of those psychical anomalies that are common to all who tic must first be substantiated, and then must one essay the reconstruction of its mechanism. The inquiry may at first prove fruitless, of course, but continuation of the search can scarcely fail to elicit tokens of mental infantilism. In pursuance of this quest we shall find ourselves face to face with the "big baby," the personification of childishness, obstinacy, and caprice; we shall encounter the peevish, the sulky, the whining; we shall see how their impotence in presence of their tic turns their nonchalance to profound despair, how their failure to adapt themselves to their malady convicts them remorselessly of volitional imperfection. The utter weakness of their will, according to Déjérine, justifies their being ranked as neurasthenics; but in the latter class of case obsessional ideas are both fugitive and fluctuating, whereas mental torticollis is dependent on a fixed idea of peculiar tenacity. There can be no doubt that such patients, however undimmed their intellectual powers may remain, ultimately fail before the everlasting obsession of their disease, and if in some cases interest in daily life and work continues unabated, a multitude of others become indifferent and apathetic, and sink into a state of physical and moral infirmity. To retrace the steps in the evolution of mental torticollis is a task not always easy of accomplishment. Very commonly the affection supervenes as the sequel to the unhindered repetition of a once voluntary purposive act, a repetition become tyrannical through volitional debility. One or two extracts from published cases will serve to illustrate the truth of our contention. 1. To escape the pain of a dental abscess on the right side, of only four or five days' duration, the patient had acquired the habit of turning the head to the right and maintaining it so for as long as possible at a time. Very shortly after the healing of the abscess, the head commenced to move involuntarily towards the same shoulder (Souques[83]). 2. Occipital neuralgia and pain in the neck led the patient to try various positions to allay the agony, in the course of which he found that rotation to the right brought transient relief. By dint of repetition the movement became involuntary (Brissaud and Meige[84]). 3. In this case the subject used to spend the whole evening inert, arms folded, without reading or working, tilting his head forwards or backwards to rediscover a "cracking" in his neck from which he suffered--a proceeding that gradually developed into a tic (Brissaud and Meige).