[Lateral hypothalamus stimulation as a conditioned stimulus for an alimentary instrumental reflex].

Dynamics of the behavioral effects of LH-stimulation which was used as a conditioned stimulus of alimentary reflex, was recorded in dogs during reflex elaboration, extinction and restoration. Before the elaboration, LH-stimulation elicited either an alimentary instrumental relflex, previously established, or a searching, sniffing, licking, orienting reaction, in the majority of cases with variable latencies. Combination of stimulation and achievement of the alimentary instrumental reflex with subsequent reinforcement in short time stabilized the feeding response. Searching, sniffing, orienting reaction disappeared during the elaboration of the conditioned reflex. Elimination of food reinforcement led to extinction of the alimentary reflex to LH-stimulation. In some sessions full abolition of the feeding response was achieved. LH-stimulation inhibitory properties are assumed. The restoration of the alimentary response to LH-stimulation after single reinforcement demonstrated a high plasticity of this structure. The dynamics of the reflex elaboration, extinction and restoration was the same in response both to brain stimulation and to distant stimuli (sound and light). The implicit motivational properties of LH-stimulation were manifested in the ability to activate the feeding behavior in the satiated dogs.