[Instrumental conditioned defensive reflex to electrical stimulation of the hippocampus in dogs]

In experiments on 6 dogs an instrumental defensive conditioned reflex was elaborated to electrical stimulation of the ventral and dorsal hippocampus. This reflex possessed the same characteristics as reflexes to distant stimuli: it became extinguished when the reinforcement was discontinued; it reappeared when the reinforcement was resumed, and it was subject to generalization. In the course of reflex elaboration, the hippocampus function underwent a substantial reorganization. Initially it consisted in inhibition of behavioural reactions; following the reflex elaboration, a general motor activity took place anticipating conditioned paw lift.