Social decision-making is a multifaceted process where decisions impact not only the individual but also the larger group. Acute stress may influence individual decision-making, potentially increasing reward-driven choices and affecting learning and adaptive adjustment. However, studies examining stress’s impact on social decision-making have presented inconsistencies, potentially arising from assessing decision-making as a singular dimension. This article aims to test, using computational modeling, the stress effect on social decision making and cognitive subprocesses involved during the Ultimatum Game (UG). Seventy-three healthy participants underwent the UG, with only half exposed before to the virtual Trier Social Stress Test (TSST-VR). In our data, prosocial behavior—as indexed by the number of accepted offers and sensitivity to unfair distributions—did not show immediate alterations 15 min following stressor onset. However, stressed participants exhibited a diminished capacity to learn and adapt during the task, alongside a more perseverative decision-making pattern. These results support the negative impact of stress on social decisions and underscore the importance of considering its effects in mitigating challenges related to social integration and cohesion.

Insufficient sleep’s impact on cognitive and emotional function is well-documented, but its effects on social functioning remain understudied. This research investigates the influence of depressive symptoms on the relationship between sleep deprivation (SD) and social decision-making. Forty-two young adults were randomly assigned to either the SD or sleep control (SC) group. The SD group stayed awake in the laboratory, while the SC group had a normal night’s sleep at home. During the subsequent morning, participants completed a Trust Game (TG) in which a higher monetary offer distributed by them indicated more trust toward their partners. They also completed an Ultimatum Game (UG) in which a higher acceptance rate indicated more rational decision-making. The results revealed that depressive symptoms significantly moderated the effect of SD on trust in the TG. However, there was no interaction between group and depressive symptoms found in predicting acceptance rates in the UG. This study demonstrates that individuals with higher levels of depressive symptoms display less trust after SD, highlighting the role of depressive symptoms in modulating the impact of SD on social decision-making. Future research should explore sleep-related interventions targeting the psychosocial dysfunctions of individuals with depression.