Event-related potential changes in chronic alcoholics.

Ten chronic alcoholics (10+ year alcoholic drinking history) and ten age and sex matched controls were tested on an ERP paradigm which elicited a large P3 component. The N1 and P2 sensory evoked potential components did not differ in amplitude or latency between the two groups. The latency of the P3 was significantly longer for the alcoholics than the controls for both a response and non-response stimulus. This finding is consistent with the results seen in a variety of dementias and is offered as evidence of the dementing effects of prolonged alcoholism in this group of subjects. While the P3 latencies were prolonged for the alcoholics, their reaction times were not different from the controls. Single trial analysis using Woody's adaptive filter also demonstrated that the single trial estimates for the 3 latency were significantly prolonged for the alcoholics. The single trial correlation between the P3 latency and each trial's corresponding reaction time was significantly greater for the alcoholics than for the controls.