Attentional inhibition or paracontrast?

In visual search experiments using asynchronous presentation of target and distractors, a robust and unexpected inhibition of reaction time was observed for the discrimination of a temporally trailing target. A number of experiments were required to determine the source of this inhibition. These experiments eliminated the possibilities that the inhibition might be a manifestation of three attentional processes: inhibition of return, attentional dwell time, or attentional capture by the temporally leading item. Other experiments eliminated the possible preattentional process of the temporal impulse response, the psychological refractory period, and a response inhibition. The characteristics of this inhibition lead to the conclusion that it is a manifestation of paracontrast.