Acute Psychosocial Stress Modulates the Detection Sensitivity for Facial Emotions.

Résumé

Psychosocial stress has been shown to alter social perception and behavior. In the present study, we investigated whether a standardized psychosocial stressor modulates the perceptual sensitivity for positive and negative facial emotions and the tendency to allocate attention to facial expressions. Fifty-four male participants underwent the Trier Social Stress Test for Groups (TSST-G) or a nonstressful control condition before they performed a facial emotions detection task and a facial dot-probe task to assess attention for positive and negative facial expressions. Saliva samples were collected over the course of the experiment to measure free cortisol and alpha amylase. In response to the TSST-G, participants showed marked increases in subjective stress, salivary cortisol, and alpha amylase compared to the control condition. In the control condition, detection performance was higher for angry compared to happy facial expressions, while in the stressful condition this difference was reversed. Here, participants were more sensitive to happy compared to angry facial expressions. Attention was unaffected by psychosocial stress. The results suggest that psychosocial stress shifts social perception in terms of detection sensitivity for facial expressions toward positive social cues, a pattern that is consistent with the tendency to seek social support for coping with stress.