Abstract: | Unit responses in the anterior zone of the suprasylvian gyrus to visual, electrodermal, and acoustic stimulation were investigated in experiments on unanesthetized cats immobilized with tubocurarine. Electrical activity was recorded from 131 units, 121 of which were spontaneously active. In 65.5% of cells responses consisted of a short or long increase or a decrease in intensity of spike activity. Most cells (58.2%) were monosensory. Responses to visual stimulation were given by 72% of neurons, to electrodermal by 61.6%, and to acoustic by 9.3%. The corresponding latent periods were 20–40, 20–30, and 15–20 msec. Responses of the same neurons to different peripheral stimuli were uniform or they differed in their dynamics. Intracellular recording gave responses in the form of EPSPs (amplitude 4–5 mV, duration 60–80 msec) or, rarely, IPSPs (amplitude 2–3 mV, duration 160–200 msec). The functional organization of the associative cortex and mechanisms of analysis of incoming afferent information are discussed.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 4, No. 4, pp. 368–374, July–August, 1972. |