Exclusionary criteria were: any neurological, acute, uncorrected or chronic medical illness; any current or recent (within six months) treatment with centrally active medications, including sedative hypnotics; and history of psychosis or schizophrenia in first-degree relatives. The presence of most Axis I psychiatric or developmental disorders was exclusionary. However, externalizing disorders were not exclusionary as these may lie on a developmental spectrum with alcoholism risk (Krueger, 1999) namely conduct disorders, attention deficit/hyperactivity disorder (ADHD), or prior substance use disorder (SUD) using DSM-IV criteria. The current sample represents the first 70 neuroimaging participants; data collection is ongoing. Subject characteristics are summarized in Table 1. Written informed consent, approved by the University of Michigan Medical School Institutional Review Board, was obtained.
