Bruandet[172] has recorded a typical example of right facial hemispasm consequent on facial neuralgia, in which, however, no certain macroscopical or microscopical lesion was detected, in either cortex or bulb. But the mere fact that no structural alteration was discovered post-mortem cannot invalidate the diagnosis; the imperfection of our methods of investigation suffices to explain the negative results of such researches. B. Tic or Spasm of the Neck--Torticollis Tic and Torticollis Spasm To make a diagnosis of torticollis, it is essential to satisfy oneself of the integrity of the bones, muscles, and articulations of the cervico-scapular region, previous to directing attention to the psychical state of the patient. In regard to the latter point, the question of heredity must not be neglected. If personal and hereditary defects are prominent, the presumption is in favour of mental torticollis; and if the convulsive movements present the characters of tic, the diagnosis is practically certain. In three cases under the observation of Fornaca,[173] for instance, there is no room for doubt. Not merely was there no sign of irritation from peripheral sources, but also no one of the three was psychically normal. Nevertheless we frequently find ourselves confronted by the question: is the movement a tic, or is it a spasm? For, strictly speaking, there are both a torticollis tic and a torticollis spasm, and their separation one from the other is often a matter of the greatest perplexity. We must refer the reader to the chapter devoted to mental torticollis for a consideration of the features of that condition, and we need not dwell on those cases of spasmodic torticollis that are obviously occasioned by irritative lesions of nervous centres or conductors. In this latter category may be placed the case put on record by Oppenheim, where torticollic spasms were produced by pressure of a cerebellar tumour on the cranial nerves. But in the affection known as hyperkinesis of the accessory of Willis we have little doubt both tics and spasms have been included. Apart from the cases of spasmodic torticollis, so called, which Babinski has published and to which reference has already been made, we may be allowed to cite one or two more, in order to exemplify the differences of interpretation to which they are liable. At the Congress of Toulouse two patients were shown by Desterac,[174] both of whom had suffered since the age of eight from a disease akin either to Friedreich's disease or to hereditary cerebellar ataxia.