Neurobehavioral and Psychosocial Predictors of Health Risk Behaviors in Adolescence and Young Adulthood

PROJECT SUMMARY Young adulthood is a developmental period during which health risk behaviors (HRBs) (e.g., substance use) peak, but the factors that lead to sustained addiction are not well understood. Current neurobiological models of risk taking focus on a developmental imbalance between the brain’s control and reward systems to explain the

typical heightened risk taking seen in adolescence. We have shown that the two systems involved in value- based decision making—i.e., the valuation system (risk and reward processing) and the control system (cognitive control)—predict HRBs in adolescence. However, patterns of brain development during adolescence that predict

continuity vs. discontinuity in HRBs in young adulthood are unknown. To fill these significant gaps, we will conduct longitudinal analyses to prospectively measure developmental trajectories of neurobehavioral mechanisms underlying HRBs throughout adolescence and young adulthood, and to characterize psychosocial

risk and resilience factors that influence these developmental trajectories. We propose that poverty, abuse, and neglect are risk factors that are linked to HRBs through their impact on neurobehavioral mechanisms underlying HRBs, and that social integration is a resilience factor that deters HRB progression during young adulthood. We

address the following aims: (1) we will assess longitudinal and bidirectional associations between valuation and control systems and HRBs from adolescence to young adulthood; (2) we will examine whether poverty, abuse, and neglect (experienced in childhood and adolescence) are associated with young adult HRBs through altered

developmental trajectories of valuation and control systems in adolescence (i.e., neurocognitive vulnerability); and (3) we will examine whether social integration mediates the link between valuation and control decision- making systems and HRBs, and moderates the effects of psychosocial stress on HRBs. This application

addresses these aims by extending a prospective longitudinal study to follow up 167 adolescents through young adulthood (23-27 yrs) who were previously assessed during adolescence (13-22 yrs). Our sample is from underserved, understudied communities with elevated substance use rates, and thus is well-poised to provide

critical insights about HRBs in at-risk populations. Our intensive longitudinal multiple-level data (11 prospective measurement occasions over 15-years) will provide an unprecedented opportunity to understand both individual differences and within-person developmental changes in neurobehavioral mechanisms underlying HRBs from

adolescence to young adulthood. The proposed study will (i) advance developmental theory regarding dynamic processes of brain-HRB associations; (ii) generate new knowledge regarding how psychosocial risk factors alter developmental trajectories of neural mechanisms underlying HRBs; and (iii) uncover neurocognitive and social

resilience factors that can be targeted for strategic intervention to prevent HRB progression and addiction.