C-42The Relation Between Verbal Fluency and Executive Functioning: An Exploratory Factor Analysis (EFA) Approach

Abstract

Objective: The purpose of the present study was to evaluate recent findings that phonemic and semantic verbal fluency were related to language processing but not executive functioning (EF). Method: 320 healthy participants (M age = 19.84, SD = 1.44; M education = 12.98, SD = 0.97; 57.8% female; 67.5% White, 23.4% African American, 4.7% Asian, 1.9% Hispanic, 1.6% Other) completed a neuropsychological battery. An exploratory factor analysis was performed using principle axis factoring and varimax rotation on measures of EF. The first three factors were extracted based on the scree plot and used as latent executive variables. The first factor (working memory) included high loadings from Auditory Consonant Trigrams, Reading Span, and Operation Span. The second factor (fluid reasoning) consisted of Raven's Advanced Progressive Matrices and WAIS-IV Visual Puzzles, Matrix Reasoning, and Similarities. The third factor (shifting/updating) was composed of the CNS Vital Signs Shifting Attention Test, WAIS-IV Digit Span, and Paced Auditory Serial Addition Test. WAIS-IV Vocabulary was used as a criterion measure of language and verbal fluency was measured using COWAT (FAS) and Animal Naming. Participants were also split into low, medium, and high verbal fluency performance groups. Results: Phonemic and semantic fluency correlated similarly with the fluid reasoning and shifting/updating factor scores and Vocabulary, with r values ranging from .22 to .34 (p values < .01). Interestingly, neither verbal fluency measure significantly correlated with working memory. Using one-way ANOVAs, there was a main effect for the verbal fluency group and all outcome variables (i.e., the fluid reasoning and shifting/updating factors and Vocabulary) except for the working memory factor (F ratios ranging from 3.93 to 10.03, p values < .05). Tukey post-hoc analyses showed that those in the low verbal fluency performance groups had significantly lower scores across all outcome measures except for the working memory factor compared to the high verbal fluency performance groups (p values < .01). Conclusion: Contrary to recent findings that verbal fluency (phonemic and semantic) was related to language but not EF, both phonemic and semantic fluency were as related to aspects of EF as they were to vocabulary knowledge.