Abstract
PURPOSE: An open question in color rivalry is whether alternation between the two colors is caused by a difference in receptoral stimulation or a difference in the neural representation of color appearance. This question was examined with binocular rivalry between physically identical lights that differed in appearance due to chromatic induction. METHODS: Perceptual alternation was measured between gratings of the same chromaticity, presented on patterned inducing backgrounds. The patterned inducing backgrounds caused the gratings, one to each eye, to appear different in color because of chromatic induction. The gratings were dichoptically presented with binocular disparity so the grating appeared in front of the background. In a control condition, perceptual alternation was measured between two physically different chromaticities on a uniform equal-energy-white background. These chromaticities matched the appearance of the identical gratings on their patterned inducing backgrounds. RESULTS: Perceptual alternation was found for the two physically identical chromaticities that appeared different due to chromatic induction. Stereoscopic depth was also perceived, indicating binocular neural combination despite color rivalry (cf. Treisman, 1962). DISCUSSION: These results show that color rivalry is resolved after color appearance is affected by chromatic context. Thus color rivalry does not require competing unequal cone excitations; the results suggest rivalry depends on the neural representation of color appearance. Further, color rivalry within a grating that appears in a different depth plane than the background corroborates separate processing of color and stereoscopic depth, with subsequent neural binding.
Supported by NIH grant EY-04802.