Hyperactivity–impulsivity, inattention, and cognitive disengagement syndrome: A meta-analytic investigation of overlapping and differential cognitive associations.

Cognitive disengagement syndrome (CDS) and attention-deficit/hyperactivity disorder-related inattention (ADHD-I) and hyperactivity-impulsivity (ADHD-HI) are often studied together, yet the differences between their cognitive profiles remain unclear. This systematic review and meta-analysis aimed to identify their cognitive correlates while controlling for symptom overlap. A total of 115 cross-sectional studies were included based on predefined eligibility criteria. Participants were children and adults, with clinical and community samples represented. Random-effects meta-analyses were conducted to examine bivariate associations between CDS, ADHD-I, and ADHD-HI symptoms with cognitive functioning. Multiple regression analyses were then applied to pooled correlation matrices to estimate cognitive correlates of each symptom dimension while controlling for shared variance between the constructs. Cognitive profiles were more similar when examined via correlations, but greater differences emerged in regression-based analyses. Among the larger multiple regression effects, ADHD-I symptoms were associated with weaker intelligence, perceptual reasoning, response inhibition, working memory, perceptual-motor functioning, and memory (βs = -.21 to -.10, p < .01). ADHD-HI symptoms were linked to weaker social cognition, focused and sustained attention (βs = -.24 to -.11, p < .001), and better motor coordination (β = .14, p < .001). CDS symptoms were associated with poorer interference control and processing speed (βs = -.29 to -.13, p < .001). Limitations include low precision for some meta-analyses and reliance on cross-sectional data. Findings support CDS as a meaningful symptom domain while highlighting the need for ADHD research that prioritizes dimensional analyses and accounts for symptom overlap. (PsycInfo Database Record (c) 2026 APA, all rights reserved).