How Personalized Behavioral Activation Interventions Improve the Behaviors of Individuals with Anhedonia

Background. Interventions for anhedonia often focus on re-engagement in pleasurable activities. We aimed to examine how anhedonic individuals changed their lifestyle behavior (i.e., physical activity, time outside, worrying, and social activity) after a personalized lifestyle advice session, and how these changes in behavior where associated with improvement. Methods. Participants were 69 young adults with persistent anhedonia, who filled out 3 assessments per day about lifestyle behaviors and affect for 3 months. After an observation month, participants received personalized lifestyle advice. Results. Results showed that only changes in social interaction, physical activity, and worrying were associated with improvement in positive affect (PA) and pleasure. Further exploration of the reciprocal associations between behaviors and PA and pleasure showed that physical activity and worrying were reciprocally associated with PA or pleasure, indicating a positive feedback loop. Conclusions. Results indicate that momentary assessments are an effective tool to detect mechanisms of change in interventions.