SPATIAL AND TEMPORAL FREQUENCY TUNING AND CONTRAST SENSITIVITY OF SINGLE NEURONS IN AREA 21A OF THE CAT

The spatial and temporal selectivities of single neurons in area 21a o f the adult cat were investigated using sinusoidal gratings. Optimal s patial frequencies and visual acuity (high cut-off frequency) were fai rly low and spatial bandwidth was mainly narrow. Contrast threshold wa s generally low but a substantial number of cells were only excited by high contrast stimuli. The temporal selectivity suggests that cells r esponded to a wide range of temporal frequencies.