Abstract

Given parallel and independent processing stteams for color and motion, it is worth to investigate the mechanism for an isduminant chromatic motion, which has long been denied but now psychophysically demonstrated in many studies. I investigated characteristics of interation chromatic motion across cardinal axes and lurninacxe motion. Using a mufti-aperture pattern and a plaid canposed of isoltuninant duotnaric gratings and luminance grating, perceived direction, motion coherence/trarupamncy, and motion repulsion were psychophysically measured. Experimental results showed the existence of chromatic motion repulsion, vectore-sum computation for perceived motion direction of chromatic plaids, and the dependency of motion coherence/transparency on the angular differrnce of component motion ditections. There was the interaction of chromatic and luminance motion. These results indicate that chromatic motion processing is very analogous to luminance motion processing. It seems that there are two processing streams, one responsible for pure chromatic modulation and the other for 2nd-order chromatic contrast profile (at low temporal frequency), suggesting there is no reason to construct a 3rd-order structure for chromatic motion.