Veridical perception of moving colors by trajectory integration of input signals.

For rapid alternations of two colors (e.g., red and green), human observers see the mixed color (yellow). This chromatic flicker fusion has been considered to reflect neural integration of color signals presented successively at the same retinal location. If so, the retinal alternation rate should be a critical fusion parameter. However, here we show that temporal alternations of two colors on the retina are perceptually segregated more veridically when they are presented as moving patterns rather than as stationary alternations at the same rate. This finding is consistent with the hypothesis that the visual system integrates color signals along the motion trajectory, in addition to at the same retinal location, for reducing motion blur and seeing veridical colors of moving objects. This hypothesis is further supported by a covariation of perceived motion direction and perceived color in a multipath motion display.