B-12: Phonemic–Semantic Fluency Dissociation in ADHD: A Common but Non–Subtype-Specific Cognitive Pattern

Abstract

Objective: Individuals with attention-deficit/hyperactivity disorder (ADHD) are often described as demonstrating relative weaknesses in phonemic compared to semantic fluency, though whether this reflects a consistent cognitive pattern or varies by presentation subtype remains unclear. This study examined the prevalence and magnitude of phonemic–semantic dissociation in a clinical ADHD sample across presentations. It was hypothesized that dissociation would be present and vary by subtype. Method/Data Selection: Participants included 531 individuals with ADHD (predominantly inattentive n = 230, hyperactive/impulsive n = 26, combined n = 275) evaluated in a neuropsychological setting. Cases with reading disorder, language-based learning disorder, or low intellectual ability were excluded. Fluency performance was indexed using normed T-scores and Delis–Kaplan Executive Function System verbal fluency scaled scores converted to z-scores. Dissociation was defined as semantic minus phonemic performance, with ≥1 standard deviation considered clinically meaningful. Results/Data Synthesis: Across methods, dissociation was significantly greater than zero (ps .14) and remained nonsignificant after controlling for age and education. Conclusions: Findings partially support the hypothesis and suggest that phonemic–semantic dissociation represents a common feature of ADHD rather than a subtype-specific profile. These results have implications for clinical interpretation of verbal fluency patterns and highlight the importance of considering dissociation as a general characteristic of ADHD.