Reduced Reward Responsiveness Predicts Change in Depressive Symptoms in Anxious Children and Adolescents Following Treatment

Abstract

Objectives: Reduced reward responsiveness, as measured by the event-related potential (ERP) component, the reward positivity (RewP), has been shown to play a role in the development of internalizing disorders, but implications for treatment remain unclear. In adult patients with anxiety and/or depression, reduced RewP has emerged as a predictor of greater change in symptoms following cognitive behavior therapy (CBT) or selective serotonin reuptake inhibitor (SSRI) treatment. The objectives of this preliminary study were to extend these findings to children and adolescents with anxiety disorders by evaluating RewP to reward as a predictor of change in anxiety severity or depressive symptoms following treatment with CBT or SSRI and to explore whether RewP differentially predicts response to one type of treatment. Methods: Patients (7-19 years old) with social and/or generalized anxiety disorder (N = 27) completed baseline measures of anxiety severity and depressive symptoms, as well as an ERP monetary reward anticipation and feedback task. RewP was measured in response to reward and breaking even feedback. Patients were then randomly assigned to CBT or SSRI treatment, and completed measures of anxiety and depressive symptom severity at the last treatment session. Results: Reduced reward responsiveness, as measured by RewP to rewards, predicted greater change in depressive symptoms following treatment, adjusting for baseline symptoms, age, and RewP to breaking even. RewP was not a significant predictor of change in anxiety symptoms. Although preliminary, exploratory analyses suggested that among anxious youth, RewP specifically predicted change in depressive symptoms following CBT, rather than SSRI. Conclusion: Results provide preliminary support for the utility of ERP measures of reward responsiveness in predicting treatment response in youth. With further research and standardization, ERP assessments could potentially be implemented in clinical settings to inform prognosis and treatment planning for youth with internalizing disorders.

Keywords: anxiety; cognitive behavior therapy; depression; event-related potentials; reward; youth.

FIG. 1.

Design of the guessing reward task. The task included 60 trials (15 win, 15 loss, 15 no-win/break even, and 15 no-loss/break even), each consisting of a decision period, anticipation period, and outcome period, separated by an intertrial interval. Analyses in this study focused on the win possible condition and the outcome stage of processing.

FIG. 2.

ERPs in response to wins, breaking even feedback (when rewards were possible), and the win minus even difference in the overall sample. The scalp distribution depicts the response to wins minus breaking even when wins were possible. ERP, event-related potential.

FIG. 3.

Scatterplot depicting RewP to reward feedback (adjusting for responses to breaking even) predicting change in depressive symptoms with treatment, and ERPs and scalp distributions depicting RewP for youth who showed high (top) versus low (bottom) change in depressive symptoms from pre-treatment to post-treatment. Note: A median split of change in depressive symptoms was computed for illustrative purposes only. ERPs, event-related potentials; RewP, reward positivity.