P300 DIFFERENCES BETWEEN NONALCOHOLIC YOUNG MEN AT AVERAGE AND ABOVE-AVERAGE RISK FOR ALCOHOLISM - EFFECTS OF DISTRACTION AND TASK MODALITY

1. P300 event-related electroencephalographic potentials were recorded from 79 young adult males, cross-classified with respect to the prese nce/absence of a family history of alcoholism (FHA) and the presence/a bsence of a personal history of antisocial personality (ASP) disorder. P300s were elicited using visual and auditory oddball tasks. Each odd ball task was repeated with a tracking task added as a distracter. 2. In general, distraction increased the latencies and reduced the amplit udes of P300s elicited by the oddball stimuli. The P300 latency increa se occurred only in low risk ASP- and FHA- groups. There was no adapti ve increase in P300 latency in the higher risk ASP+ and FHA+ groups. 3 . Group differences in P300 were restricted to visual tasks. No interp retable group differences in P300 latency or amplitude were found duri ng the auditory tasks.