Morphology of the prefrontal cortex predicts body composition in early adolescence: cognitive mediators and...

Morphological features of the lateral prefrontal cortex (PFC) in late childhood and early adolescence may provide important clues as to the developmental etiology of clinical conditions such as obesity. Body composition measurements and structural brain imaging were performed on 11 226 youth at baseline (age 9 or 10 years) and follow-up (age 11 or 12 years). Baseline morphological features of the lateral PFC were examined as predictors of body composition. Findings revealed reliable associations between middle frontal gyrus volume, thickness and surface area and multiple indices of body composition. These findings were consistent across both time points and remained significant after covariate adjustment. Cortical thicknesses of the inferior frontal gyrus and lateral orbitofrontal cortex were also reliable predictors. Morphology effects on body composition were mediated by performance on a non-verbal reasoning task. Modest but reliable moderation effects were observed with respect to environmental self-regulatory demand after controlling for sex, race/ethnicity, income and methodological variables. Overall findings suggest that PFC morphology is a reliable predictor of body composition in early adolescence, as mediated through select cognitive functions and partially moderated by environmental characteristics.