The Depressed Decision-Maker: How Value-Based Decision-Making Differs in Major Depressive Disorder
Mukherjee, D., Lee, S., Kazinka, R., Sattherwaite, T. D., & Kable, J. W.
Depression is clinically characterized by obvious changes in decision-making that cause distress and impairment. Though several studies suggest impairments in depressed individuals in single tasks, there has been no systematic investigation of decision-making in depression. Here compare clinically depressed participants (n = 64) to healthy controls (n=64) using a comprehensive battery of nine value-based decision-making tasks. Depressed participants performed worse on punishment (p = .003, d = .56) and reward learning tasks (p = .03, d = .37), were less willing to wait in a persistence task (p = .008, d = .39), and expressed more pessimistic predictions regarding winning money in the study (p = .01, d = .44). However, depressed participants did not differ in their time, risk, or ambiguity preferences, nor did they differ in their social bargaining behavior. Performance on learning, expectation, and persistence tasks each loaded on unique dimensions in a factor analysis and accounted for unique variance in predicting depressed status. Decision-making performance alone could predict depressed status out-of-sample with above 70% accuracy. These results confirm hints from single task studies that depression has the strongest effects on reinforcement learning, expectations about the future, and persistence. Although the predictive accuracy of decision-making tasks may not be clinically meaningful for current diagnostic categories, our results highlight several decision processes that are the impacted in major depression, and whose further study could lead to a more detailed computational understanding of distinct facets of this heterogeneous disorder.