RESPONSES OF CELLS IN CATS AREA-17 TO RANDOM-DOT PATTERNS - INFLUENCEOF STIMULUS SIZE

WE have investigated both the response of cells in the striate cortex to a moving random dot pattern (visual noise) and the extent to which these responses depend on stimulus size. Cell receptive fields (RF) we re classified according to the level of modulation of their response t o sinusoidal gratings and the spatial arrangement of their ON and OFF regions. Our results indicate that most complex and simple cells respo nd to visual noise. The amplitude of these responses depend largely on the area of the visual field that was stimulated. Most cells were opt imally activated when the noise covered a region much larger than the RF. Our results suggest that the area beyond the classical RF may cont ribute to the cells' responsiveness to noise.