Time Course of the Change in Colour Appearance after the Disappearance of Adaptation Light

Abstract

Colour appearance depends on the adaptation process which is considered to lie at the various levels from the retinal photoreceptor to the cortical higher cognitive levels. Because of the transient chemical characteristics of human photoreceptors, the pattern of the monocular chromatic after-effect after the disappearance of adaptation light was measured in both eyes in order to know the balance of the effects of photoreceptors and high-cognitive process. Most changes in the colour appearance recovered to the same state as that before adaptation as time progressed; this finding suggested the retention of colour appearance before adaptation. And the continuous changes in the after-effects from hue of green to red suggest that the opponent colour mechanism plays an important role in chromatic adaptation. Further, the hue of aftereffects should be decided by the comparison of the inputs from 3 types of photoreceptors after the opponent-colour mechanism. Therefore, chromatic after-effects are caused by a high-order cortical process functions in chromatic adaptation.