CORD POTENTIALS IN SPINAL SHOCK MULTIPLE STIMULI

Publisher Website
Google Scholar
Abstract
In the spinal Macaca mulatta monkey, inhibition of the internuncial response to the 2d of 2 volleys to an afferent nerve is contingent upon the presence of a positive wave in the preceding cord potential. In the absence of such positivity, internuncial recovery from refractoriness is complete in 20 to 25 msec. Repetitive stimulation gives a series of internuncial potentials in which little positivity is added to that incident to the initial volley. Such a pattern contrasts sharply with that obtained from peripheral nerve and hence suggests a perikaryal origin and different units for the sources of negativity and positivity respectively. The acutely spinal monkey gives no contraction of semi-tendinosus in response to afferent stimulation by either single or multiple volleys. The chronic monkey yields a large contraction to single volleys to which little is added by further stimulation even at frequencies at which the cord potentials are but slightly reduced. The view is advanced that in even the chronic monkey there persists a considerable degree of depression down stream from the internuncials recorded, presumably at the motoneurones.

This publication has 1 reference indexed in Scilit: