In summary, it is not possible to say whether the reduction in P3b observed in the current study is entirely the result of genetic vulnerability in a subset of individuals or has a contribution from the effects of alcohol abuse in TNAD. Either is consistent with our observation of a much smaller decrease in P3b in TNAD compared to the decrease observed in LTAA. TNAD have both a lower family history density of alcoholism than LTAA, less severe externalizing propensity, and less severe alcohol dependence as measured by all indices of alcohol consumption. Longitudinal examination of P3b in TNAD may provide data relevant to the cause of the P3b reduction observed herein.
