Event-related potentials in chronic alcoholics during withdrawal and abstinence

Twenty-one chronic alcoholics were submitted to an "oddball" auditory event-related potentials (ERP) paradigm and to the Wechsler Memory Scale (WMS) after four weeks' abstinence. Eight of these patients were also submitted to the same ERP procedure and to two WMS items (digit span and associations) during a minor withdrawal state in the first days of hospitalization. Alcoholics showed reduced N1-P3 and N2-P3 amplitudes as compared to control subjects. Three alcoholics showed a P3 latency that exceeded the age-corrected control range (2 SE). There was no correlation between neuropsychological performances and electrophysiological measures, but the three subjects with abnormal P3 latencies had lower WMS scores. During withdrawal, greater N1-P2 amplitudes and shorter P3 latencies were observed as well as poorer performances on the two WMS items. The results are discussed in view of the possible contributions of ERPs in the understanding of the effects of chronic alcohol intake and alcohol withdrawal on CNS functions.