LAUSR

ABSTRACT According to the threat-capture hypothesis, irrelevant-but-salient stimuli interfere more with a visual search task when they are perceived as threatening. We investigated the neural basis for behavioural interference in conditions that promote attentional suppression of distracting stimuli (i.e., easy search with predictable targets). In Experiment 1, participants discriminated the shape of a neutral target (a flower), which competed for selection with a threat-related or neutral distractor (spider or leaf, respectively). In line with prior results, we observed larger behavioural interference from spider than leaf distractors. Electrophysiological recordings revealed a posterior positivity between 200 and 300 ms, the PD, suggesting that participants actively suppressed both leaf and spider distractors. Critically, the PD was delayed with spider compared to leaf distractors. Experiment 2 was a control experiment where we confirmed that the results depended on the execution of the peripheral search task. When participants performed a localization task on the fixation cross, the decisive results from Experiment 1 were not replicated despite equal peripheral stimulation. Our results indicate that the behavioural delay incurred by threatening stimuli is accompanied by a delay of suppressive mechanisms. Conversely, we found no evidence for initial capture followed by suppression that may be predicted by hypervigilance-avoidance theory.