Neural correlates of attentional capture in visual search.

Much behavioral research has shown that the presence of a unique singleton distractor during a task of visual search will typically capture attention and thus disrupt target search. Here we examined the neural correlates of such attentional capture using functional magnetic resonance imaging in human subjects during performance of a visual search task. The presence (vs. absence) of a salient yet irrelevant color singleton distractor was associated with activity in the superior parietal cortex and frontal cortex. These findings imply that the singleton distractor induced spatial shifts of attention despite its irrelevance, as predicted from an AC account. Moreover, behavioral interference by singleton distractors was strongly and negatively correlated with frontal activity. These findings provide direct evidence that the frontal cortex is involved in control of interference from irrelevant but attention-capturing distractors.