Adjusting behavior after reward or punishment is important to adaptively respond to change. Previous studies have shown that stress can change feedback responsiveness, which is often disturbed in psychiatric disorders. In this study, we experimentally induced stress by the Trier Social Stress Test and examined the effects on cortisol levels, state anxiety, and performance on a reward- and punishment-based reversal learning paradigm. Forty-five healthy young women were tested in an experimenter-blind between-subjects design.
Based on their cortisol response, participants were divided into low (a decrease in cortisol) and high responders (an increase in cortisol). The public speech increased anxiety in both groups compared to controls. Performance analysis showed that low responders reacted faster than high responders. Additionally, low responders showed higher reward than punishment responsiveness, the reverse was true for the high responders. This study suggests that reward and punishment sensitivity can be modulated by changing stress levels, which might hold promises for the treatment of psychiatric disorders related to disturbed reward or punishment responsiveness.