PT  - JOURNAL ARTICLE
AU  - M Hallett
AU  - B T Shahani
AU  - R R Young
TI  - EMG analysis of stereotyped voluntary movements in man.
AID  - 10.1136/jnnp.38.12.1154
DP  - 1975 Dec 01
TA  - Journal of Neurology, Neurosurgery & Psychiatry
PG  - 1154--1162
VI  - 38
IP  - 12
4099  - http://jnnp.bmj.com/content/38/12/1154.short
4100  - http://jnnp.bmj.com/content/38/12/1154.full
SO  - J Neurol Neurosurg Psychiatry1975 Dec 01; 38
AB  - EMG activity was recorded in biceps and triceps while subjects voluntarily flexed their elbows during a visual matching task. With fast flexion, the initial EMG was characterized by a triphasic pattern with a burst of activity first in biceps, then in triceps with a silent period in biceps, and finally in biceps again; these components were analysed quantitatively. Smooth flexion was characterized by continuous activity in biceps. Inhibition of tonic activity of triceps in relation to a fast flexion occurred in the 50 ms before the initiation of biceps activity. A patients with a severe pansensory neuropathy performed normally on these tasks. Physiological mechanisms underlying these patterns are analysed; an important conclusion is that the triphasic activity with fast flexion is 'centrally programmed'.