Impairment of semantic and figural memory by acute ethanol: age-dependent effects

Alcohol drinking is prevalent among young adults in the U.S. Moreover, heavy drinking is acknowledged by a substantial percentage of young adults in both college and military subpopulations, despite the known cognitive demands associated with these endeavors and the cognitive impairments associated with alcohol usage. We assessed the acute effects of ethanol (0.6 g/kg) on the acquisition of both semantic and figural memory in a sample of young adults from 21 to 29 years of age using a repeated-measures, placebo-controlled experimental design. Ethanol significantly impaired memory acquisition in both domains. In addition, the effect of ethanol on three of the four memory measures assessed was dependent on the age of the subjects. Subjects in a young subgroup (21 to 24 years of age) were significantly more impaired in memory measures than those in the subgroup that was 25 to 29 years of age. These results indicate a divergence of the potency of ethanol against memory acquisition across a narrow age range in early adulthood. Whereas these data are preliminary, and should be generalized cautiously, they are also consistent with a growing literature using animal models that indicates that acute ethanol is a more potent antagonist of memory and memory-related hippocampal activity in adolescent animals compared with adults.