Alcohol impairs speed of information processing and simple and choice reaction time and differentially impairs higher-order cognitive abilities.

Previous research has demonstrated that alcohol impairs information processing. However, it is unknown whether this impairment is on all stages of information processing, or on the early, rather than on the later, stages of information processing. Thus, the aim of the present study was to examine the effects of orally administered alcohol on both the early and the later stages of information processing. The present study assessed inspection time (IT), simple reaction time, choice reaction time and cognitive ability (Wechsler Adult Intelligence Scale - Revised) in 16 adult participants in both alcohol and placebo conditions. IT (a measure of the early stages of information processing) was used as a predictor variable in a linear regression to examine whether a disruption of the early stages of information processing accounted for changes in total information processing after alcohol administration. Results indicated that alcohol significantly slowed total information processing, independently of the early stages of information processing.