Brain regions with gestational age differences mediate cognition in adolescents born very premature

Being born prematurely is known to have wide and diverse effects on neural development, some of which persist into adolescence. Currently, little research exists regarding the mediating and longitudinal effects of these neuronal differences into adolescence. Using ~2100 subjects from the Adolescent Brain and Cognitive Development study, a longitudinal cohort of adolescents (aged 10-14), identified as premature, and matched full-term peers, we conducted a canonical correlation analysis of their grey matter volume and fractional anisotropy. We also performed cross-sectional and longitudinal linear modeling with behavioral and cognitive measures and mediation analyses. Adolescents born more than 9 weeks premature showed reduced GM and increased FA in regions of the brain that are critical to attentional processes, memory, executive function, cognitive control, problem solving, and information processing. These differences mediated the relationship with cognition and persisted across four years of development. Neuronal changes associated with very premature birth are long-lasting and explain in part their lower cognitive functioning.