Task-Rest Reconfiguration Efficiency of the Reward Network Across Adolescence and its Association With Early Life Stress and Depressive Symptoms

Objective Adolescents face significant changes in many domains of their daily lives that require them to flexibly adapt to changing environmental demands. To shift efficiently among various goals, adolescents must reconfigure their brains, disengaging from previous tasks and engaging in new activities. Method To examine this reconfiguration, we obtained resting-state and task-based fMRI scans in a community sample of 164 adolescents. We assessed the similarity of functional connectivity (FC) of the reward network between resting state and a reward processing state, indexing the degree of reward network reconfiguration required to meet task demands. Given research documenting relations among reward network function, early life stress (ELS), and adolescent depression, we examined the association of reconfiguration efficiency with age across adolescence, the moderating effect of ELS on this association, and the relation between reconfiguration efficiency and depressive symptoms. Results We found that older adolescents showed greater reconfiguration efficiency than younger adolescents and, further, that this age-related association was moderated by the experience of ELS. Conclusion These findings suggest that reconfiguration efficiency of the reward network increases over adolescence, a developmental pattern that is attenuated in adolescents exposed to severe ELS. In addition, even after controlling for the effects of age and exposure to ELS, adolescents with higher levels of depressive symptoms exhibited greater reconfiguration efficiency, suggesting that they have brain states at rest that are more strongly optimized for reward processing than do asymptomatic youth.