Attention-deficit/hyperactivity disorder (ADHD) and working memory in adults: a meta-analytic review

Abstract

Objective: Within the last decade, working memory (WM) has garnered increased interest as a potential core deficit or endophenotype of attention-deficit/hyperactivity disorder (ADHD). The current study is the first meta-analytic review to examine several subject and task moderator variables' (e.g., percent female, diagnostic selection procedure, trials per set size, response demands, type of dependent variable, and central executive [CE] demands) effect on between-group phonological (PH) and visuospatial (VS) WM in adults with ADHD, relative to healthy controls.

Method: Literature searches were conducted using the PsycINFO, Web of Science, and PubMed databases, and yielded 38 studies of WM in adults with ADHD.

Results: Results revealed moderate-magnitude between-group effect sizes (ESs) across both WM domains. In addition, several task-moderating variables explained significant ES variability among PH and VS studies.

Conclusions: Collectively, these findings indicate that WM deficits persist into adulthood and suggest that methodological variability may explicate why WM deficits have not been uniformly detected in previous experimental studies.