[An electrophysiological analysis of the process of a shift in a dominant]

Abstract

Correlation of electrical activity of the sensorimotor (representation of the forelimb and blinking and visual areas of rabbit cerebral cortex and VPL of the thalamus was studied by the method of spectral analysis during creation of the motor defensive dominant (by serial electrical stimulation of the forelimb) at the background of the blinking dominant. In the structures which realize the defensive reflex (sensorimotor cortex and VPL of the thalamus) a typical for the dominant state increase in the spectral power was observed in the delta range. This electrophysiological phenomenon was not accompanied by behavioural manifestations of the dominant. Formation of the latent defensive dominant destroyed the typical for the dominant state organization of biopotentials in the cortical structures responsible for realization of the blinking reflex. It seems likely that the blinking dominant in the process of its change for the defensive one inhibits behavioural manifestations of the new dominant focus.