Influence of piracetam on activity of neurons of the neocortex of rabbits during learning.

Abstract

1. Against the background of the action of piracetam, a cyclic derivative of GABA in a dose of 200–400 mg/kg, significant changes were not observed in the probabilities of motor reactions of awake rabbits to light flases, reinforced by electrocutaneous stimulation of the extremity, and to flashes switched on against the background of a conditional inhibitor without reinforcement. 2. Piracetam in the dose employed did not affect the inhibitory pauses in the reactions of neurons of the visual area, and the late components corresponding to them of the potential evoked in response to non-reinforced light flashes, i.e., did not intensify the inhibitory hyperpolarizational processes in the cerebral cortex. 3. Following the administration of piracetam, the differentiation of inhibitory and reinforced light flashes improved, according to bioelectrical indices of the operation of the brain, as the result of the intensification of the effect of painful reinforcement on the neurons of the cortex. 4. These experiments revealed substantial differences in the neurophysiological mechanisms of action of piracetam and fenibut, a linear derivative of GABA, which are classified as nootropic agents.