Perception of one event is affected by another event (modulator) that occurs either before or after the event (prediction and postdiction). A possible account for these temporal interactions is that the processing of an event does not start immediately, but waits a constant period for potentially relevant input. This hypothesis predicts that the perceptual latency of the target event is invariant to changes in the timing of modulator presentation. We tested this prediction by measuring the reaction time to judge an ambiguous motion event either as “bounce” or “stream” while changing the modulator (sound or flash) timing. The results showed that the modulator timing had little effect on RT for “stream” perception, but significantly modulated RT for “bounce” perception—the earlier the modulator, the shorter the RT. These results reject the constant delay hypothesis, but suggest more situation-adaptive temporal processing such as accumulating perceptual evidence over time.

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.