Poster Presentations Thursday, April 28, 1977

patient’s muscle biopsy of his extensor digitorum communis was morphologically normal. The best approach to the study of neuromuscular pathophysiology is a combination of morphologic, histochemical, and electrophysiologic results. Correlating single-fiber responses to electrical stimulation with standard nerve conduction techniques quantifies the amount of branching. never exceeded the tremor frequency. In contrast, the single motor units activated during essential tremor formed a homogenous group in which each unit in essential tremor did not appear to follow the usual rank order of recruitment. Such clearly definable abnormalities of single motor unit behavior permit a categorization which suggests fundamental differences in certain of the physiologic mechanisms underlying these three different tremors.