Alcohol and false recognition: a dose-effect study.

Abstract

The pattern of acute memory impairment produced by alcohol is similar to that produced by the benzodiazepines. However, in contrast to demonstrations that benzodiazepines decrease false recognition rates, results of a recent study suggest that a low dose of alcohol increases false recognition rates; false recognition refers to the phenomenon of mistakenly claiming that one has been exposed previously to a novel item. This study was designed to examine the acute dose-effects of alcohol on false recognition. Effects of alcohol (0.27 and 0.60 g/kg) on performance in the Deese/Roediger-McDermott false recognition paradigm were examined in a repeated measures placebo-controlled double-blind design in 18 healthy volunteers. The 0.60 g/kg dose of alcohol significantly reduced true recognition rates (measured by hit rate) and induced a more conservative response bias (measured by C) relative to placebo; however, neither alcohol dose significantly impaired participants' sensitivity in discriminating between old and new words (d'). Neither alcohol dose affected false recognition rates. Effects of alcohol on false recognition and on response bias may differ from those observed previously with benzodiazepines. A direct comparison at equivalent doses will be necessary to draw conclusions about qualitative differences between alcohol and benzodiazepines.