Figure 8.
Effect of relative center-surround response gain on the generation of chromatic cells. A total of 5000 model cells were generated with a relative surround gain, ks, randomly assigned as 0.5–0.9 times the response gain of the center. Cells were binned as a function of their relative surround gain and cone purity index plotted for receptive field center (x axis) versus surround (y axis). A, Distribution of chromatic and achromatic cells with ks equal to 0.5–0.6 times that of the center; 30% of cells (379 of 1276) were chromatic. B, Distribution of chromatic and achromatic cells with ks equal to 0.6–0.7 times that of the center; 39% of cells (481 of 1251) were chromatic. C, Distribution of chromatic and achromatic cells with ks equal to 0.7–0.8 times that of the center; 48% (616 of 1291) of cells were chromatic. D, Distribution of chromatic and achromatic cells with ks equal to 0.8–0.9 times that of the center; 64% (757 of 1182) of cells were chromatic.