Receptive fields of neurons in the lateral suprasylvian area of the cat

Abstract

The structure of receptive fields of single neurons in the lateral suprasylvian area of the cat's cortex was studied. Receptive fields of neurons in this area are larger (up to 2000 deg2 or more) than those of the visual projection cortex. A difference was found in the sizes of these fields of the same neuron when measured by presentation of a black object and spot of light. Experimental results showed that most neurons of the area (104 of 148) that are sensitive to visual stimulation respond clearly to flashes of a stationary spot of light. Because of this feature the structure of the receptive fields of the neurons were studied by point by point testing of their whole surface. Intensities of on- and off-components of on-off neurons were found to differ. Only 16% of receptive fields had equal numbers of discharges in on- and off-components of the on-off response. Dominance of one component was observed in 84% of on-off neurons. Receptive fields with several discharge centers are a characteristic feature of neurons in this area. A concentric organization of the receptive fields was found in 11% of neurons.