Influence of extirpation of the sensorimotor area of the cortex on the formation of conditioned reflexes in response to a complex signal in the ontogenesis of the cat.

The influence of the extirpation of the sensorimotor cortex (SMC) on the formation and maintenance of a previously developed alimentary conditioned reflex to a simultaneous complex stimulus (light + sound) with extinction of the reaction to unreinforced components of the complex signal was studied in kittens aged 39 days to 4 months. The extirpation of the SMC prior to 2.5 months of age had no influence on either the formation or maintenance of the conditioned reflex to the complex signal developed prior to the operation. The extirpation of the SMC in preliminarily trained kittens aged 3.5 months and older leads to disinhibition of the differential components when the positive conditioned reflex to the complex signal is maintained. In untrained kittens of the same age the extirpation of the SMC was manifested in the animals' incapacity to inhibit the motoric reaction to the differential signal. The question of the role of the SMC in ontogenesis during the formation of adequate forms of behavior which require the achievement of intersensory interactions is discussed.