Flexible processing of distractor stimuli under stress

TL;DR

This study shows that acute stress affects how the brain uses irrelevant information during decision-making, even if overall attention remains stable.

Contribution

The study reveals stress reduces the use of predictive distractor information for response selection, despite stable attentional control.

Findings

Stressed participants showed reduced lateralized readiness potential for predictive distractors.

Behavioral and sensory EEG markers of attention were unaffected by stress.

Stress may impair the use of irrelevant but predictive information during response selection.

Abstract

Acute stress is assumed to affect executive processing of stimulus information, although extant studies have yielded heterogeneous findings. The temporal flanker task, in which a target stimulus is preceded by a distractor of varying utility, offers a means of investigating various components involved in the adjustment of information processing and conflict control. Both behavioral and EEG data obtained with this task suggest stronger distractor-related response activation in conditions associated with higher predictivity of the distractor for the upcoming target. In two experiments we investigated distractor-related processing and conflict control after inducing acute stress (Trier Social Stress Test). Although the stressed groups did not differ significantly from unstressed control groups concerning behavioral markers of attentional adjustment (i.e., Proportion Congruent Effect), or event-related sensory components in the EEG (i.e., posterior P1 and N1), the lateralized readiness potential demonstrated reduced activation evoked by (predictive) distractor information under stress. Our results suggest flexible adjustment of attention under stress but hint at decreased usage of nominally irrelevant stimulus information for biasing response selection.

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