P300 from normals and adult children of alcoholics.

The P300 event-related brain potential (ERP) was obtained from 24 pairs of undergraduate male subjects. One member of each pair reported having a father who was alcoholic (FH+), the other reported no alcoholic family member (FH-). Pairs were matched on height, weight, academic performance, and personal drinking history. Three auditory task situations were employed which manipulated stimulus discrimination difficulty. All tasks employed 20% target and 80% standard tones randomly presented with the subjects required to move their index finger whenever a target tone was detected. No differences in P300 amplitude or latency were obtained between the groups. FH+ subjects tended to demonstrate decreased amplitudes with increased amounts of reported alcohol consumption but only for the most difficult task. The results of the present study suggest that the relationship between the P300 and the heritability for alcoholism is not yet clear and may be modulated by differences in task requirements, subject populations, and personal drinking history.