In conclusion, our several analyses of ERPs in an informative sample of young adult twins suggest that novel P3 amplitude correlates negatively with alcohol use and abuse, an association that may reflect altered involuntary attention attributable to gene–environment interactions of dispositional vulnerabilities with high-density drinking histories. This could suggest an impaired involuntary attention shifting from interactive genetic–environmental effects. Novel P3 latency, which was attributed to gene–environment interactions, also correlated positively with alcohol use. We conclude by emphasizing again that drinking patterns of our twin subjects were studied from mid-adolescence into young adulthood with their ERP assessments conducted at a mean age of 25 years; and that of the multiple measures of alcohol use we related to P3, high-density drinking yielded the most consistent evidence. Our results suggest that subtle neurophysiological changes in sound processing and in attention and orienting to environmental changes can be induced by alcohol use during adolescence and early adulthood. That suggestive result invites and awaits definitive confirmation.
