[Interrelation between signal and reinforcing stimuli at the cellular level during extinction of motor conditioned reflexes].

Comparative analysis of extinction of neuronal activation conditioned reactions in the motor cortex, the ventromedial and perifornical hypothalamic nuclei attest that the connection between the signal and reinforcing components of pairings in these structures of alert rabbits is more stable in defensive conditioned reflexes than in conditioned reflexes to time. A more stable connection between two components is established during conditioning in neurones of the motor cortex and the perifornical nucleus, and a less stable one at the level of the hypothalamic ventromedial nucleus and the medial geniculate body. In conditioned reflex to time a more stable connection has been detected in neurones of the motor cortex, the medial geniculate body and the perifornical nucleus, a less stable connection in the neurones of the hypothalamic ventromedial nucleus.