Auditory P3 findings in mission Indian youth

Native Americans have some of the highest rates of alcohol abuse and dependence, yet potential biological risk factors associated with the problem drinking seen in many tribes remain relatively unknown. In this study, the amplitude of the P3 component of the event-related potential (ERP), a measure associated with risk for alcoholism in European-American youth, was investigated in Mission Indians.

The study participants were Mission Indian children and adolescents (N = 68, 37 male) between the ages of 7 and 13 years. ERPs were collected using two auditory "oddball" paradigms: an easy and a difficult discrimination task. P3 amplitude and latency were statistically evaluated as a function of age, gender, degree of Native American heritage (NAH) and family history (FH) of alcohol dependence.

P3 latency was found to vary as a function of age and gender, with girls demonstrating greater decreases in latency with age than boys. suggesting a faster maturation time. Whereas there were no significant relationships between NAH and P3 latency, those participants with at least one alcoholic parent had longer P3 latencies elicited by the difficult auditory task. No significant relationships were found between P3 amplitude generated to the target tones and any of the variables (age, gender, FH, NAH).

Mean P3 amplitudes and latencies obtained from these Mission Indian youth were within the range of those values reported in the literature for samples of children and adolescents of other ethnicities. Although the amplitude of the P3 ERP measure has been associated with FH of alcoholism in studies of predominantly European-American individuals, P3 amplitudes generated in response to these auditory tasks did not robustly differentiate Mission Indian children and adolescents who may be at higher risk for alcoholism from those presumed to be at lower risk.