Cooperation in Mood Disorders 1 RUNNING HEAD: Cooperation in Mood Disorders Increased Cooperative Behavior across Remitted Bipolar I Disorder and Major Depression: Insights Utilizing a Behavioral Economic Trust Game

Mood disorders impact social functioning, but might contribute to experiences—like affective distress—that might result in increased cooperative behavior under certain circumstances. We recruited participants with a history of bipolar I disorder (n = 28), major depressive disorder (n = 30), and healthy controls (n = 27) -to play a wellvalidated behavioral economic Trust Game, a task that provides a well-controlled experimental scenario to measure cooperative behavior for the first time across both groups. Both mood-disordered groups cooperated significantly more than the control group, but did not differ from one another. These results suggest that, in some contexts, a history of mood disturbance can produce enhanced cooperation, even in the absence of current mood symptoms. We discuss the clinical significance of enhanced cooperation in mood disorders and point to key directions for future research.