A study examined the association between adolescent alcohol use and working memory (WM) using a large population sample.
Data from the Avon Longitudinal Study of Parents and Children were used to investigate the association between alcohol use at age 15 years and working memory 3 years later, assessed using the N-back task (N ~ 3300). Participants were categorised, based on consumption patterns as low alcohol users, frequent drinkers or frequent/binge drinkers. Adjustment was made for potential confounders.
There was evidence of an association between frequent/binge drinking (compared to the low alcohol group) and poorer performance on the 3-back task after adjusting for sociodemographic confounding variables, working memory at age 11 years, and experience of a head injury/unconsciousness before age 11 years (β = -0.23, 95% CI = -0.37 to -0.09, P = 0.001). However, this association was attenuated (β = -0.12, 95% CI = -0.27 to 0.03, P = 0.11) when further adjusted for baseline measures of weekly cigarette tobacco and cannabis use. Weaker associations were found for the less demanding 2-back task. The researchers found no evidence to suggest frequent drinking was associated with performance on either task.
In conclusion, the study found weak evidence of an association between sustained heavy alcohol use in mid-adolescence and impaired WM 3 years later. Although the researchers comment that they cannot fully rule out the possibility of reverse causation, several potential confounding variables were included to address the directionality of the relationship between WM and alcohol use problems.
Source: Alcohol Use in Adolescence and Later Working Memory: Findings From a Large Population-Based Birth Cohort. Mahedy L, Field M, Gage S, Hammerton G, Heron J, Hickman M, Munafò MR. Eur J Nutr. 2018 Jan 11. doi: 10.1007/s00394-018-1613-5.