[Comparative assessment of the role of the primary and secondary somatosensory regions of the cerebral cortex during conditioned reflex behavior in animals].

The first (SI) and second (SII) somatosensory cortical areas were ablated in one group of cats after preliminary learning of tactile differentiation of rough and smooth surfaces of the floor coating in a special chamber. Somatosensory areas were ablated in another group after learning an adequate choice of the reinforcement side in response to a bell and a metronome. Unilateral and bilateral ablation of SI affected but little the elaboration and achievement of the above acts. Unilateral and bilateral ablation of area SII resulted in a sharp impairment of the tactile differentiation of the surfaces (35% correct responses after unilateral and 26% after bilateral ablation) and a less pronounced disturbances in the choice of the side of reinforcement in response to the bell and the metronome (80% of correct choice after unilateral and 72% after a bilateral ablation.