Effect of alcohol on genetically determined variants of the normal electroencephalogram.

The effect of a single dose of alcohol on the electroencephalograms (EEGs) of healthy male carriers of extreme variants of the EEG was examined. The EEG variants included: low voltage, borderline alpha, diffuse beta, and monotonous alpha EEG. The EEGs were analyzed on a small processor by means of a program for interval-amplitude analysis. The synchronizing effect of alcohol (increase of alpha activity and decrease of variance of frequency) was most pronounced in the borderline alpha EEG. As the interindividual variability of the resting EEG is known to be genetically determined, it can be concluded that the differential effects of ethanol on the EEG have a genetic basis.