Acute effects of ethanol on motor performance and movement-related brain potentials.

The acute effects of ethanol on skilled motor functions were examined in male social drinkers, under four doses ranging from 0 (placebo) to 1.05 g/kg lean body weight. The movement entailed a forewarned choice transitive motion of the arm and hand, aimed at a flanking target. Performance measures disclosed only small effects of ethanol on speed and accuracy of movement. The simultaneously-recorded movement-related brain potentials disclosed decreased involvement of frontal and posterior brain areas, suggesting that ethanol disrupted the planning and regulation of movement despite the overall preservation of reaction speed.