[Study of the H-reflex of human hand muscles using the post-stimulus histogram method]

The method of post-stimulus histograms of the single motor unit potentials permits the under-threshold facilitation to be revealed and the antidromic blocking of H-reflex to be avoided up to sub-maximal for M-response stimuli. The H-reflex was revealed only under abnormal conditions and was not observed in the noraml subjects. In the experiments the motoneurons responded to impulses from above, therefore the inhibition of the motoneurons itself cannot be a mechanism of the H-reflex inhibition. The alternative explanation is the presynaptic inhibition.