Saccadic reaction time (SRT) is more strongly slowed by target-similar than dissimilar distractors (similarity effect). The time course of this similarity effect was investigated by varying target contrast and analyzing SRT distributions. With foveal distractors, the similarity effect increased with increasing SRT, suggesting that top-down…

In the Simon effect, participants make a left or right keypress in response to a nonspatial attribute (e.g., color) that is presented on the left or right. Reaction times (RTs) increase when the response activated by the irrelevant stimulus location and the response retrieved by instruction are in conflict. The authors measured RTs and movement…