Reward learning impairment and avoidance and rumination responses at the end of Engage therapy of late-life depression

Abstract

Objectives: This study examined the association between reward processing, as measured by performance on the probabilistic reversal learning (PRL) task and avoidance/rumination in depressed older adults treated with Engage, a psychotherapy that uses “reward exposure” to increase behavioral activation. Methods: Thirty older adults with major depression received 9 weeks of Engage treatment. At baseline and treatment end, the 24-item Hamilton Depression Rating Scale (HAM-D) was used to assess depression severity and the Behavioral Activation for Depression Scale (BADS) to assess behavioral activation and avoidance/rumination. Participants completed the PRL task at baseline and at treatment end. The PRL requires participants to learn stimulus-reward contingencies through trial and error, and switch strategies when the contingencies unexpectedly change. Results: At the end of Engage treatment, the severity of depression was lower (HAM-D: t(19) = −7.67, P