Neurophysiological processes in the striopallidum in shaping of avoidance reactions

Abstract

Analysis of evoked potentials (EP) (which are criteria of the brain structures' involved in integration processes) dynamics served as a basis to investigate participation of the caudate nucleus (Cd), the globus pallidum (GP) and the thalamus ventrolateral nucleus (VL) in two types of the adaptive behavior securing: defensive avoidance reaction and perception learning. The results prove the notion that neurophysiological processes change in brain structures by adaptive reactions forming in dogs (Adrianov, 1980; Popova, 1980). Goal-directed motor component presence in the adaptive behavior was revealed as the determining factor of the Cd, GP and VL involvement in the system's processes. It was found that the dynamics of the Cd, GP and VL involvement in defensive habit central organization are determined both by motor response forming and signal and reinforcing stimuli functional significance change: the Cd, GP and VL functioning "regime" dependence on relationship were shown between these external elements of the adaptive behavior system. The Cd is involved in the central integration by two variants: the first one is formed under influence of afferent actions stipulated by the signal stimulus onset; the other one under the influence of afferentations complex from the motor response executive apparatus. The GP functioning "regime" is formed during the significance settling of the light stimulus trigger. Variations of VLs involvement in the system processes is determined by the possibility of reinforcement in the defensive behavior system.