Validation of human behavioral tests using ethanol as a CNS depressant model.

This study evaluated the sensitivity of a battery of tests proposed for use in determining the depressant effects of chemicals on human central nervous system (CNS) function. The first step in the development of such tests was to determine if the tests could detect the effects produced by a known CNS depressant, ethanol. Five behavioral tests, digit span memory, simple reaction time, tachistoscopic perception, flicker fusion and anticipation timing (velocity estimation) were evaluated to determine their sensitivity to the effects of ethanol at blood levels between 0.05-0.06%. Thirty-one adult male volunteers received 0 and 1.4 ml 100 proof vodka/kg body weight according to a double-blind crossover design. Tests were conducted before treatment and between 30 and 70 minutes after an ethanol or control drink was ingested. Multivariate analysis of variance (MANOVA), using composite scores representing the individual tests, indicated that the battery as a whole detected statistically significant ethanol effects. Repeated measures analysis of variance (ANOVA) comparing performance after drinking ethanol to control performance on each of the individual tests indicated a significant decrement in reaction time, tachistoscopic perception and anticipation timing.