CHRONIC PROGRESSIVE CHOREA

The mechanism of the production of choreo-athetotic movements, in spite of careful and thorough histopathologic studies, is still inadequately explained. It is believed by some that choreic movements can be explained solely by disease of the ganglion cells or fiber system of the striatum. S. A. K. Wilson1was of the opinion that the "problem of all involuntary movements, as tic, epilepsy, tremor, chorea, athetosis, myoclonus, etc., is one of physiology" and not of pathology. It was his contention that the "choreic disturbance manifests itself through the cortico-spinal system." The latter must be in a relatively intact condition for the appearance of hyperkinetic symptoms. For eleven years he had had under observation a patient with senile chorea in whom the choreic movements were limited to the right side of the body. Pathologically, the left postcentral convolution was shrunken to nearly half its size, while the entire left corpus striatum