RAPID COLOR-SPECIFIC DETECTION OF MOTION IN HUMAN VISION

THE human visual system is much better at analysing the motion of lumi nance (black and white) patterns than it is at analysing the motion of colour patterns(1-4), especially if the pattern is presented very bri efly(5) or moves rapidly(6). We report here that observers reliably di stinguish the direction of motion of a colour pattern presented for on ly 17 milliseconds, provided that the contrast is several times the th reshold value (the contrast needed to detect the presence of the patte rn). A control experiment, in which a static luminance 'mask' is added to the moving colour pattern, proves that discrimination of the direc tion of motion of these brief stimuli is colour-specific. The mask dra stically impairs discrimination of the direction of motion of a lumina nce pattern, but it has little effect on a colour pattern. We conclude that the human visual system contains colour-specific motion-detectio n mechanisms that are capable of analysing very brief signals.