Linking negative affect, personality and social conditions to structural brain development during the transition from late adolescent to young adulthood

Background: The transition from late adolescence to early adulthood is a period that experiences a surge of life changes and brain reorganization caused by internal and external factors, including negative affect, personality, and social conditions. Methods: Non-imaging phenotype and structural brain variables were available on 497 healthy participants (279 females and 218 males) between 17 and 22 years old. We used sparse canonical correlation analysis (sCCA) on the high-dimensional and longitudinal data to extract modes with maximum covariation between structural brain changes and negative affect, personality, and social conditions. Results: Separate sCCAs for cortical volume, cortical thickness, cortical surface area and subcortical volume confirmed that each imaging phenotype was correlated with non-imaging features (sCCA |r|range: 0.21-0.38, all pFDR < 0.01). Bilateral superior frontal, left caudal anterior cingulate and bilateral caudate had the highest ca-nonical cross-loadings (|p| = 0.15-0.32). In longitudinal data analysis, scan-interval, negative affect, and enthusiasm had the highest association with structural brain changes (|p| = 0.07-0.38); at baseline, intellect and politeness were associated with individual variability in the structural brain (|p| = 0.10-0.25). Limitations: The present study used non-imaging variables only at baseline, making it impossible to explore the relationship between changing behavior and structural brain development. Conclusions: Individual structural brain changes are associated with multiple factors. In addition to time -dependent variables, we find that negative affect, enthusiasm and social support play a numerically weak but significant role in structural brain development during the transition from late adolescence to young adulthood.