Abstract

The adopted assumptions are as follows: (1) At each point on the retina there are at least four concurrent receptive fields of parvocellular color-opponent geniculate units, two ON-center OFF-surround units (subtypes +R – G, +G – R) and two OFF-center ON-surround units (subtypes –R + G, –G + R). (2) All units receive excitatory E and inhibitory I inputs. Both E and I are expressable as the product of a spectral and spatiotemporal function, implying that spectral and spatiotemporal sensitivities are separable. Spatial and temporal sensitivities are not assumed to be separable. (3) Concurrent geniculate units interact by pairs on first-stage cortical cells adding or subtracting their signals. The analysis shows the chromatic and spatiotemporal implications of the proposed interactions.

© 1988 Optical Society of America