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. 1979 Feb;42(2):161–170. doi: 10.1136/jnnp.42.2.161

Characteristics of the F response: a single motor unit study.

S K Yates, W F Brown
PMCID: PMC490182  PMID: 422964

Abstract

Trains of 100 to 200 stimuli result in F discharges from less than one half of motor units of hand muscles. The maximum observed F discharge frequency was 10%. There was no relation between the surface voltage of motor unit potentials and the frequency of F discharge. The motor unit potentials of larger surface voltage were recruited at higher stimulus intensity levels, usually supramaximal for the antidromic sensory nerve action potential. No correlation was observed between F latency and the surface voltage of the motor unit potentials. In only one pathological example was a clear interaction observed between the frequency of F discharge in motor unit potentials and the recruitment of other single motor unit potentials by increments in the stimulus intensity. The observations suggested that caution should be exercised before the F discharge is accepted as a method for measuring proximal conduction times in human motor nerves.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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