To investigate further the validity of the VBM results in males, additional SPSS analyses were performed on the extracted gray matter volumes of the fusiform, insula, and inferior temporal cortex. A mixed model SPSS analyses was performed using a family identifier to control for multiple sibling pairs within the sample. Relevant covariates were included in a mixed model analysis. These included ICV and prenatal exposure to alcohol, drugs and cigarettes. Also, included was whether or not the participant had received a diagnosis of substance use disorder before the scan. Initial models included all covariates with subsequent analyses removing non-significant covariates.
