The Relationship between Linguistic Disfluencies and Cognitive Abilities in School-aged Children with and without Vocabulary Delay

Objectives: This study aimed to examine the characteristics of linguistic disfluencies during story generation and retelling tasks and to investigate an association between linguistic disfluencies and cognitive abilities in narrative samples. Methods: A total of 49 children aged 7-10 (20 children with vocabulary delay and 29 typically developing children) participated. Participants completed the story generation and retelling task. Children’s utterances were analyzed into four categories of mazes: fillers, repetitions, revisions, and pauses. Participants also completed three working memory tasks that assess phonological loop, episodic buffer, and visuospatial sketchpad. Results: First, both children with vocabulary delay and typically developing children produced a greater total number of utterances in the narrative retelling task than in the narrative generation task, and children with vocabulary delay showed higher rates of pauses. Also, children with VD showed a higher rate of pauses in the generation task than the TD group and higher rates of filled pauses, pauses, and the total number of mazes in the retelling task. For the TD group, expressive vocabulary was the best predictor for the use of mazes during a story-generation task, whereas receptive vocabulary was the best predictor for the use of mazes during a story-retelling task. Nonword repetition was a significant predictor in children with VD. Conclusion: Results showed children with vocabulary delay had higher mazes rates than typically developing peers. Also, different cognitive factors explained the linguistic disfluencies of the two groups. Results suggest that vocabulary and working memory need to be considered for interventions aimed at children’s fluent speech.