Table 2 summarizes the linear regressions results, controlling for the primary covariates (full results in eTables 6-8). Relative to unexposed individuals, cannabis users had smaller left amygdala (~2.3%) and right VS volumes (~3.5%). Post-hoc comparisons (eTable 9) showed similar volumetric differences in those who used <100 or ≥100 times, with no statistical difference between the regression coefficients across these levels of use. Among cannabis users, heavier use predicted smaller left hippocampus volumes (though this effect did not pass FDR correction). There were no significant associations with age of onset of use (eTable 8). These results remained significant when also controlling for a variety of personality factors, impulsivity, other substance use, and psychiatric history (eTable 10).
