[Reactions of neurons of the secondary somatosensory cortex of awake cats to electrocutaneous and acoustic stimulation].

In chronic experiments on alert cats the discharges of neurons in the secondary projection zone of the somato-sensory cortex to click and electrical stimulation of contralateral paw were investigated. 57% of neurons responded to "specific" stimulation by increasing the discharge frequency, 18%--by weakening or stopping the background activity, while 25% did not react at all. 30% of neurons responded by activation to the "non-specific" stimulation (click), 25%--by inhibition and 45% were unresponsive. An investigation of intersensory convergence by sending signals from different analyzer systems showed that bimodal responses are peculiar to most neurons (55%) of this zone. 18% of neurons with a response only to the "specific" or "non-specific" stimuli were found. It is suggested that polysensory convergence on the neurones of the somato-sensory cortex is important for the cortical area in the process of closing of conditioned connections.