Brain structure correlates of circulating endocannabinoids and related lipids in early adolescents.

The endocannabinoid (eCB) system underlies many biological processes and is thought to be critical in adolescent brain development. However, the eCB system's contributions to brain morphometry during adolescence remains understudied. Here we investigated cross-sectional associations between brain structure and circulating eCBs and related lipids in a subsample of adolescents (N = 294, ages 10-14, 44.5% female, 65.3% White) from the Adolescent Brain and Cognitive Development (ABCD) study utilizing a structural equation modeling approach. After accounting for sex and age, significant covariance between circulating eCBs and related lipids and cortical thickness, surface area, and volume in brain regions throughout the cortex were revealed. While the mechanisms underlying these associations need further research, these results suggest that the eCB system likely plays a critical role in early-adolescent brain development. Future work should determine underlying mechanisms, evaluate these associations longitudinally, and consider sex differences and the modulatory effects of pubertal hormones.