Phonological working memory is adversely affected in adults with anorexia nervosa: a systematic literature review

Abstract

Purpose Cognitive restraint has potentiating and deleterious effects on working memory (WM) in anorexia nervosa (AN). Conflicting evidence may be due to heterogeneity of tasks examining different WM components (e.g., verbal/auditory versus visuospatial), and differences in adolescent versus adult AN. Additionally, differential cognitive profiles of restricting versus binge/purging subtypes, comorbid psychiatric disorders and psychotropic medication use may confound findings. Methods To address these conflicts, 25 studies, published between 2016 and 2021, investigating WM in children, adolescents and adults with AN were systematically reviewed using PRISMA guidelines. Results In 71% of WM tasks, no difference in performance between AN patients and age-matched controls was reported, while 29% of WM tasks showed worse performance. Adults with AN displayed deficits in 44% of the verbal/auditory tasks, while performance remained unaffected in 86% of visuospatial tasks. Conclusion Examining age groups and WM subsystems separately revealed novel findings of differentially affected WM components in AN. Comorbidities and psychotropic medications were common among AN participants and should be regarded as critical confounding factors for WM measures. Future studies examining different components of WM, acknowledging these confounding factors, may reveal specific deficits in AN to aid treatment improvement strategies. Level of evidence I, systematic review.

Back to the future: Progressing memory research in eating disorders

“…As with episodic memory, much of the research on working memory in EDs has focused on evaluating general impairments (or enhancements) of working memory (e.g., lower working memory capacity for words, digits, and other neutral stimuli, impaired ability to ignore food‐related and neutral distractors when utilizing working memory, impaired working memory updating), and the results to date have been similarly mixed (Brooks, 2016; Voon, 2015). For example, some studies suggest that individuals with restricting‐type EDs, such as AN, may have increased working memory capacity compared with individuals with binge‐spectrum EDs or controls (Brooks et al, 2012; Dahlén et al, 2022; Israel et al, 2015), though other studies have found reduced capacity in AN or no difference between groups (Fowler et al, 2006; Weider et al, 2016). Research in BED and BN has produced similarly mixed evidence for general working memory dysfunction.…”