Objective Memory Impairment in Post-Traumatic Stress Disorder: a Systematic Review and Multilevel Meta-Analysis of Trauma-Exposed Adult Populations.

Abstract

Background: Post-traumatic stress disorder (PTSD) is traditionally conceptualized as a disorder of fear learning and emotional dysregulation; however, accumulating evidence indicates that objective cognitive dysfunction, particularly memory impairment, represents a core and enduring feature of the disorder. Prior quantitative syntheses have been limited by heterogeneous control groups, pooling of disparate cognitive outcomes, and inadequate handling of statistical dependence across outcomes. Objective: This systematic review and meta-analysis is aimed at determining whether trauma-exposed adults diagnosed with PTSD exhibit objective impairments in memory performance compared with trauma-exposed adults without PTSD. Methods: A comprehensive search of PubMed/MEDLINE, Embase, PsycINFO, and Web of Science was conducted up to December 17, 2025. Eligible studies included trauma-exposed adults (≥18 years) with PTSD diagnosed using DSM or ICD criteria and a trauma-exposed non-PTSD comparator group. Objective neuropsychological measures of verbal episodic memory and working memory were extracted. Risk of bias was assessed using the Newcastle-Ottawa Scale. Standardized mean differences (Hedges' g) were pooled using multilevel random-effects meta-analytic models to account for within-study dependence. Results: Ninety studies met the criteria for the systematic review, of which 88 contributed quantitative data to the meta-analysis. Across studies, individuals with PTSD demonstrated significantly poorer memory performance compared with trauma-exposed controls without PTSD. Impairments were most consistent for verbal episodic memory and working memory, with effects observed across diverse trauma types and assessment instruments. Considerable heterogeneity was present but did not negate the overall pattern of PTSD-specific cognitive impairment. Sensitivity analyses confirmed the robustness of findings. Although funnel plot asymmetry suggested possible publication bias, trim-and-fill-adjusted estimates remained statistically significant. Conclusions: Trauma-exposed adults with PTSD exhibit reliable and clinically meaningful impairments in objective memory performance beyond the effects of trauma exposure alone. These findings support conceptualizations of PTSD as a disorder involving maladaptive memory processing and underscore the importance of incorporating cognitive assessment and intervention into PTSD research and clinical care.