Figure 3.

Push–pull organization of cone inputs to cone-opponent cells in V1. Most L-ON-center neurons (red dots) were both excited by L+ stimuli and suppressed by L− stimuli, indicated by the location of the responses within quadrant IV (left plot). Similarly, M-ON-center neurons (green spots) were excited by L− and suppressed by L+, indicated by the location of the responses within quadrant II (left plot). Push–pull functional organization was also seen for L-ON and M-ON cells to the M stimulus (middle plot). Blue–yellow neurons showed push–pull to the L and M stimuli less often (most blue and yellow dots in quadrants I and III, L and M plots). Peak responses at the center location were determined using Equation 4 (see Materials and Methods). Error bars show the SD of the firing rate of each neuron. For χ² values describing the distribution of the cells within the plots, see supplemental Table 1A–C.