The effects of acute stress on behavioural and ERP measures of human attentional networks

Neurobiological models suggest that acute stress facilitates bottom-up stimulus processing while impairing top-down executive control. To test this hypothesis, the present study investigated the effects of acute stress on behavioural (reaction time and accuracy) and electrophysiological (N1 and P3 ERP component amplitude) measures of the alerting, orienting, and executive attentional networks. Forty-three right-handed females aged 18-34 were recruited and performed the Attention Network Test (ANT) before and after the Maastricht Acute Stress Test (MAST) or a non-stressful MAST-placebo. Subjective Units of Distress Scale (SUDS) ratings and salivary cortisol concentrations were further collected as manipulation checks. While the manipulation checks revealed a successful stress induction, the hypothesised detrimental effect of acute stress on executive function was not found for reaction time (`p`=.524), accuracy (`p`=.657), or P3 amplitude (`p`=.408). Similarly, the hypothesised beneficial effect of stress on bottom-up stimulus processing was not found for measures of reaction time (`p`=.857) or N1 amplitude (`p`=.107). Supplementary analyses indicated that these findings were unrelated to the magnitude or duration of the stress response induced by the MAST, instead suggesting that the ANT itself may be insensitive to the effects of acute stress. Future research may utilise alternate versions of the ANT to address this possibility.