Acute Stress Enhanced Healthy Young Males' Inhibitory Control of Avoidance Behavior to Negative Scenes

Maladaptive responses to approach-avoidance conflict (AAC) are common in various stress-related disorders. Acute stress exerts complex effects on approach/avoidance motivation and inhibitory control, both of which are critical for AAC resolution and influenced by prefrontal cortex (PFC) activation. To investigate the impact of acute stress on AAC related to emotional scenes, 53 healthy male participants completed a scene approach-avoidance task (AAT) after either the Maastricht Acute Stress Test or a control procedure, with functional near-infrared spectroscopy data of the PFC collected during the AAT. Participants also rated their approach-avoidance tendencies toward the scenes posttask. The stress manipulation was successful. In the control group, the compatibility effect was observed, with significantly lower accuracy for approaching negative scenes compared to avoiding negative scenes and approaching positive scenes. However, this compatibility effect was absent in the stress group. The stress group made fewer errors than the control group when approaching negative scenes. As there were no group differences in the approach-avoidance tendency ratings, we speculated that acute stress enhances inhibitory control rather than altering motivation. Stress deactivated the PFC during approaching negative scenes, indicating a limited role of top-down processing in AAC resolution. Additionally, in the stress group, reaction times were longer for avoiding negative scenes compared to avoidances to positive ones, reflecting the poststress freeze-like response. These findings provide behavioral and neural signatures of the effects of acute stress on responses to AAC, offering potential evidence for the early identification of acute stress and stress-related disorders.