[Characteristics of the coding of light stimulus intensity by visual cortex neurons during light adaptation in the cat].

Response of 70 neurons in area 17 of the visual cortex to optimal stimuli of different intensity in the receptive field under conditions of photopic adaptation were analyzed in unanesthetized cats. The reaction threshold, differential sensitivity, optimal intensity and the width of the brightness range were estimated. No intensity detectors were found in this area. 70% of neurons studied had inhibitory distortion in the range of their intensity functions. The neurons differed in their threshold reactions by 5-6 orders, in dynamic range--by 3-4 orders, and in differential sensitivity--by 2-3 orders. The visual cortex neurons with receptive fields in central and periphery parts of the visual field had different intensity functions.