Working Memory Performance Following Acute Alcohol: Replication and Extension of Dose by Age Interactions

Despite the substantial number of older adult drinkers, few studies have examined acute alcohol effects in aging samples. We have explored these interactions across a variety of neurobehavioral domains and modalities and have consistently observed age-contingent vulnerabilities to alcohol-associated decrements in neurobehavioral functions. However, these studies have not been sufficiently powered to address sex differences, and, thus far, no attempt has been made to replicate results. The current study addresses these gaps.

The study used a double-blind, placebo-controlled, factorial design with two age groups (older, 55-70 years; younger, 25-35 years) and three doses (target breath alcohol concentrations: .00, .04, and .065 g/dl). Replication analyses used an independent sample (n = 90) to replicate age-contingent alcohol effects reported by Boissoneault (n = 90). Samples were combined (N = 180; 91 women) to enable sex analyses. The dependent measure was performance efficiency in a visual working memory task.

A complex interaction between sex, age, and dose, F(2, 178) = 4.15, p = .02, appeared driven by age-contingent divergence in working memory performance, which was most pronounced between women at the .065 dose, t(28) = 4.61, p < .01, d = 1.68. Replication analyses revealed a pattern of age differences consistent with previous results, although the previously reported age by alcohol interaction failed to reach statistical significance.

Results provide further support for the hypothesis that neurobehavioral effects of acute alcohol are age dependent and offer evidence that this interaction may be moderated by sex. Extensions of this work are needed to identify underlying processes and ascertain the functional impact of these effects on the health and well-being of aging adult drinkers.