The influence of the stimulation of the CA3 field of the dorsal hippocampus on the motor polarization dominant in rabbits.

The influence of the stimulation of the CA3 field of the dorsal hippocampus on the course of a motor polarization dominant produced by the action of a constant current on the sensorimotor area of the rabbit cortex was investigated. It was demonstrated that stimulation of the hippocampus by a 1 mA current (0.5 msec; 100 Hz; 0.2 sec) against the background of the optimum of the dominant elicits its [the dominant's] inhibition, which is manifested in the suppression of the motor "dominant" reaction of the forelimb in response to test stimuli, and in the abolition of the coherent associations of the theta-range electrical activity of the sensorimotor cortex and the CA3 field of the dorsal hippocampus. On the other hand, stimulation of the hippocampus with a weak current (30-50 microA; 0.5 msec; 30 Hz; 0.2 sec) at the optimum of the dominant reinforces it [the dominant], eliciting a movement of the "dominant" extremity, and against the background of an unstable dominant promotes it activation and stabilization and restores the dominant in the following days during its extinction.