Auditory P3 findings in Mission Indian youth

Objective: 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 stu dy, 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. Method: The study participants were Mi ssion 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 wer e statistically evaluated as a function of age, gender, degree of Native Am erican heritage (NAH) and family history (FH) of alcohol dependence. Result s: 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 b etween NAH and P3 latency, those participants with at least one alcoholic p arent had longer P3 latencies elicited by the difficult auditory task. No s ignificant relationships were found between P3 amplitude generated to the t arget tones and any of the variables (age, gender, FH, NAH), Conclusions: M ean P3 amplitudes and latencies obtained from these Mission Indian youth we re 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 re sponse to these auditory tasks did not robustly differentiate Mission India n children and adolescents who may be at higher risk for alcoholism from th ose presumed to be at lower risk.