Attentional capture by size singletons is determined by top-down search goals.

The question whether attentional capture by salient visual stimuli is driven by bottom-up salience or is contingent on top-down task set is still under dispute. We show that the ability of size singletons to capture attention is determined by current search goals. Participants searched for small or large target singletons among medium-size distractors. Attentional capture by small or large size singleton cues that preceded target search displays was reflected by spatial cueing effects and N2pc components. These effects were observed only when these cues matched the current target-defining feature, but not for physically identical but mismatching cues. Results demonstrate that attentional capture by size singletons is not driven by bottom-up salience, but is controlled by feature-specific task settings.