Acute stress impairs error monitoring and post-error adjustment

Stressor presents a risk factor in everyday life by not only triggering stress responses in the body but also influencing cognitive processing. Previous research has shown that the medial frontal cortex and dorsolateral frontal cortex, on which error processing depends, are susceptible to acute stress. However, few studies have explored the effect of stress on error processing. It is still unclear whether individuals with acute stress can effectively detect their own error responses and how acute stress influences the transfer from error monitoring to post-error adjustment. To address these issues, we recruited 52 healthy male participants and randomly assigned them into stress (n = 26) or control (n = 26) groups. The participants were first asked to undergo an acute stress test or control-stress test and soon after that perform an error awareness task. Acute stress was induced by the Trier Social Stress Test (TSST) which consists of a public speech task and a mental arithmetic task. The error awareness task was a motor go/no-go response inhibition task, in which the participants marked the responses where they recognized errors. Additionally, information on the participants' heart rates, subjective emotional states, and perceived stress levels was collected to evaluate their immediate reaction to stress. Finally, we used salivary cortisol levels to explore the delayed reaction to stress during the experiment. The acute stress induction was indexed by the increases in free cortisol levels, heart rates, perceived stress levels, and negative affect in the stress group compared with the control group. Two main findings were obtained in this study. First, the accuracy of error awareness in the stress group was lower than that of the control group, and the negative affect under acute stress was negatively predictive of the accuracy of error awareness in the stress group but not the control group, suggesting that acute stress led to poor error monitoring. Second, the accuracy of the first trials after aware errors was significantly lower than that after unaware errors in the stress group, but there was no change in the control group, showing that post-error performance was impaired following acute stress. Altogether, the present study demonstrated that participants could not effectively identify error responses after acute stress, and their post-error adjustment was impaired even when the error responses were identified. Our results show that stress plays an important role in error processing, which is consistent with the biphasic-reciprocal model that proposes that stress responses enhance the activation of the amygdala but impair neural functioning in the prefrontal cortex. In conclusion, the present study demonstrates that acute stress impairs the performance monitoring system, which leads to impaired post-error adaptive behaviors.