Impairment of cognition, risk-taking, and self-perception by alcohol.

The effects of alcohol on risk-taking, visual signal detection, and perceptual-motor skills were examined under controlled conditions. Skill in two videogame tasks (driving and racquetball simulations) was unaffected by a massive dose of alcohol, whereas risk-taking in the driving task was increased. Alcohol also impaired performance on the signal-detection task, decreasing both perceptual vigilance and caution (d' and beta). The dependent measures yielded minor correlations with personality and biographical variables, although men were more skilled and riskier in their behaviour than women. A second experiment employing the signal-detection task indicated that even moderate doses of alcohol can significantly impair visual perception and perceptual decision making. Both studies showed that subjects who receive a massive dose of alcohol (bac .12% or .16%) significantly underestimate the amount consumed, and rate themselves as being much less than totally drunk.