Exploration-related strategy mediates negative coupling between decision-making performance and psychiatric symptoms

Abstract

Various psychiatric symptoms are often accompanied by impairments in decision-making. Given the high comorbidity of psychiatric disorders, symptoms that specifically couple with the impairment remain unidentified. The computations involved in decision-making that mediate the coupling are also elusive. Here, we conducted an online experiment with healthy individuals (n=939), participating in a decision-making task and completing questionnaires about psychiatric symptoms. The questionnaire data identified two dimensions underlying various symptoms: the first is mainly associated with obsessive-compulsive traits whereas the second is associated with depression and anxiety. Furthermore, by model-based analysis, we found only the first dimension was negatively correlated with the overall performance of the decision-making task, and the negative correlation was mediated by choice stochasticity (random exploration) and propensity to choose options previously unchosen. Given that the preference for previously unchosen options can reflect uncertainty-driven exploration, our findings highlight a key role of exploration-related strategies in psychiatric deficits of decision-making.