Acute, withdrawal, and chronic alcohol effects in man: event-related potential and quantitative EEG techniques.

The results presented here strongly suggest that quantitative electroencephalography and event-related potentials are excellent research tools and may be clinically useful as non-invasive monitors of psychotropic drug action and encephalopathies. Our initial data with acute mild alcohol intoxication show that acute tolerance may be reflected in qEEG but not in P3 latency. Since predictably some brain functions may show tolerance, and others not, these approaches may be useful probes. The amplitude of N1-P2 appears to differentiate alcoholics with and without a history of withdrawal seizures. This technique may thus prove useful in determining treatment and monitoring treatment effects in alcohol withdrawal. P3 latency appears to be normal in Korsakoff's syndrome, unlike in Alzheimer's disease. The combination of the event-related potentials with neuropsychology and magnetic resonance imaging scans should be invaluable for future research in these patient groups. Many patients with severe liver disease superficially appear mentally intact. The event-related potential and quantitative electroencephalography findings we have demonstrated may indicate those at greater risk for alterations in brain functioning. These techniques may also prove useful in diagnosing other "subclinical" encephalopathies and further our understanding of the underlying brain pathophysiology.