ELECTROPHYSIOLOGICAL OBSERVATIONS ON AN UNUSUAL, TASK SPECIFIC JAW TREMOR

A patient with no other neurological signs or symptoms presented with a prominent tremor restricted to the mandible. This 5-6 Hz tremor was interesting in that it was normally confined to the digastric muscles and was highly task specific. In the course of her normal daily activi ties, it began only when the patient drank from a cup or glass. The lo calisation of this tremor to a muscle that has no muscle spindles and no reciprocal inhibitory reflexes suggests that such tremors must be c apable of being generated centrally.