Following post-operative occlusion of the right internal carotid artery, a 65-year old man developed abnormal left involuntary movements which appeared in upright position or at exercise and disappeared in sitting or supine positions. The clinical and electroencephalographic features of these movements could have been epileptic. However, this case together with data from the literature suggest that transient ischemic episodes in the carotid territory may be expressed as involuntary movements occurring in certain positions, betraying a severe and abrupt fall in cerebral blood flow.