Attentional repulsion effects produced by feature-guided shifts of attention.

Attention shifts to particular objects in the visual field can distort perceptual location judgments. Visual stimuli are perceived to be shifted away from the current focus of attention (the attentional repulsion effect [ARE]). Although links between repulsion effects and stimulus-driven exogenous attentional capture have been demonstrated conclusively, it remains disputed whether AREs can also be elicited as a result of feature-guided attention shifts that are controlled by endogenous task sets. Here we demonstrate that this is indeed the case. Color singleton cues that appeared together with equiluminant gray items triggered repulsion effects only if they matched a current task-relevant color but not when their color was irrelevant. When target-color and nontarget-color singleton cues appeared in the same display, AREs emerged relative to the position of the target-color cue. By obtaining independent behavioral measures of perceptual repulsion and electrophysiological measures of attentional capture by target-color cues, we also showed that these two phenomena are correlated. Individuals who were more susceptible to attentional capture also produced larger AREs. These results confirm the existence of links between task-set contingent attentional capture and AREs. They also provide the first direct demonstration of the attentional nature of these effects with online brain activity measures: perceptual repulsion arises as the result of prior feature-guided attention shifts to specific locations in the visual field.