Reinforcement learning is positively associated with anhedonia symptoms

Impairments in reward-related behavior in everyday life are characteristic of major depressive disorder and closely linked with anhedonia. While previous research has suggested a negative relationship between reward-related behavior and symptoms of depression or anhedonia, findings across clinical and non-clinical studies are mixed. We conducted three online studies, recruiting a combined 629 nonpatient online participants. The studies consisted of an exploratory study, a preregistered replication, and data from a separate study utilizing a distinct learning task. Participants completed reinforcement learning tasks where they learned to select either the more rewarding response or more rewarding stimulus, as well as a large set of self-report measures of symptoms and traits. Contrary to expectations, we observed a positive association between reinforcement learning performance and anhedonia symptoms across all three studies. General depression symptoms showed one positive association and two null associations with performance. Our results contrast with the assumption of a negative association between reinforcement learning behavior and symptoms of depression or anhedonia. Instead, our results suggest that in large non-selective samples, anhedonia symptoms can be positively associated with reward-guided learning and decision-making.