THE CEREBRAL PEDUNCLE AND ITS RELATION TO NORMAL AND ABNORMAL MUSCULAR ACTIVITIES

　 The case of a 41 year old woman who suffered from left-sided choreo-athetoid movements following an attack of rheu-matic fever with carditis at the age of eleven years is reported. The right ante-rior white column of the cervical spinal cord was cut without material benefit. Several years later most of the middle third of the right cerebral peduncle was divided. This is the portion of the pedun-cle known to contain the pyramidal tract. For 18 days after this operation she had no abnormal involuntary movements what-soever although voluntary movements recovered quickly to an almost normal level. This observation is incomplete as there has been no opportunity to examine the brain and determine the extent, nature and location of the lesions present there. However, from the facts available it seems likely that voluntary movements of nearly normal extent and strength can be pro-duced in the contra-lateral extremities even though the pyramidal tract has been largely divided in the cerebral peduncle, and that there are certain fibers in or near the cen-tral third of the cerebral peduncle which are concerned with the production of the abnormal involuntary movements of choreo-athetosis. It seems possible that if these fibers can be found and destroyed such abnormal movements can be abolished without producing any considerable degree of paralysis of normal muscular activity.