A comparison of the effect of lorazepam on memory in heavy and low social drinkers.

The cognitive deficits, particularly memory impairment, observed in association with organic brain damage caused by chronic alcohol ingestion, are consistent with the profile of benzodiazepine-induced amnesia. This study examined the cognitive capabilities of a group of heavy social drinkers (n = 11) and a group of low social drinkers (n = 11) under the influence of a pharmacological challenge (lorazepam 2 mg) and a placebo treatment. Lorazepam impaired visual memory and verbal learning in both groups, but the effect of lorazepam was exacerbated in the heavy social drinkers for delayed recall of verbal material. Heavy social drinkers had lower verbal fluency scores and were less able to copy complex figures than low social drinkers whether or not the pharmacological challenge was present. Lorazepam induced deficits, in both groups, which confirmed to the classic profile of those observed in benzodiazepine-induced amnesia. The deficits, both in the absence and presence of lorazepam, shown by heavy social drinkers suggest that changes may have occurred in their brain functioning.