Fig. 6: Nonlinear chromatic integration is linearized under local stimulation.
From: Linear and nonlinear chromatic integration in the mouse retina
a Schematic view of the local chromatic-integration stimulus, showing that multiple, spatially separated locations are stimulated simultaneously with different contrast combinations. Time courses of displayed contrast for one of the stimulation spots are shown below the frames of the top row. b Chromatic-integration curves from the responses of a sample cell for the receptive field center and eight stimulus grid locations around the center. Shaded regions around the curves show mean ± SEM. To the right, the cell’s chromatic-integration curve for the full-field stimulus is shown for comparison (top), and the Gaussian fit to the receptive field (orange, 1.5-sigma contour) is displayed relative to the spot locations, with a grayscale-encoded maximum of the local chromatic-integration curve. c–e Chromatic-integration curves of a linear (c), a nonlinear Off (d), and a nonlinear On (e) cell, as determined from the full-field chromatic-integration stimulus. The display style is analogous to the example in b, but the local chromatic-integration curves are only shown for the location selected for analysis. Error bands show mean ± SEM. f Comparison of chromatic nonlinearity indices between full-field and local stimulation for linear, nonlinear Off, nonlinear On, and nonlinear On–Off cells. The distributions differ significantly for each of the nonlinear cell classes (linear cells: p = 0.12; nonlinear Off cells: p = 8.9 × 10−12; nonlinear On cells: p = 5.1 × 10−12; nonlinear On–Off cells: p = 1.0 × 10−41; two-sided Wilcoxon signed-rank test, statistics summary: ***p < 0.001, n.s. not significant). g Comparison of the relative sensitivity to UV stimuli under local versus full-field stimulation for the four distinguished cell classes.
