Longitudinal associations between adolescent adversity, brain development and behavioural and emotional problems.

Adolescent adversity could have lasting effects on mental health, potentially through neurodevelopmental changes. This study used a random intercept cross-lagged panel model to examine how adverse experiences, brain development, and behavioural and emotional problems are linked over time in the ABCD study (N ≈ 12.000, USA). We found a positive association between family conflict and behavioural and emotional problems: family conflict was related to increased problems at 10 - 12 years (β = 0.06, p = 0.002), and vice versa. At 12 - 14 years, behavioural and emotional problems were also related to increased family conflict (β = 0.20, p < 0.001). Neighbourhood perception was related to behavioural and emotional problems and white matter microstructure. At 10 - 12 years, low neighbourhood safety was related to lower levels of white matter microstructure (β = -0.04, p = 0.041) and vice versa. It was also associated with more behavioural and emotional problems (β = 0.05, p = 0.015) and vice versa. Behavioural and emotional problems were positively associated with neighbourhood perception for adolescents with more friends (χ²(1) = 9.82, pBonf. = 0.02). These findings underscore the need to consider socio-environmental adversity when examining adolescent brain development and mental health.