PROJECT SUMMARY This application seeks to understand brain network organization and environmental mechanisms underlying risk and resilience pathways of psychiatric disorders in premature children. Infants born very preterm (VPT; <30 weeks gestation) are 2-4 times more likely than Term Control (TC) children to report ADHD, anxiety, and social- communication deficits as adolescents. VPT children also show higher rates of internalizing and socioemotional problems, which are known precursors to later risk for psychiatric disorders. However, a developmental account of how internalizing symptoms change over time is missing from this literature. Understanding how VPT children progress along trajectories of internalizing symptoms is necessary to identify sensitive windows when clinical interventions may be most effective. I propose to use a longitudinal cohort of VPT and TC children followed from birth to age 10 to examine individual trajectories of internalizing symptoms as a function of neural organization and individual and environmental factors that may predict risk or resilience. Specifically, I will 1) examine internalizing trajectories as a function of infant neural organization and dyadic caregiver-child interactions at age 2, 2) model stability and change in dyadic caregiver-child interactions from age 2 to 5 as a function of infant health risk and maternal stress, and 3) use an autoregressive Cross-Lagged Panel Model to model longitudinal and transactional relations across internalizing symptoms, neural organization, and dyadic caregiver-child interactions from birth to age 10. By examining these brain-behavior-context associations with a developmental lens, we will better capture neurodevelopmental and environmental mechanisms of risk and resilience translatable for prevention and intervention across typical and atypical populations.