A longitudinal study on the effect of executive function on stuttering improvement in preschool children

This longitudinal study examined whether executive function predicts stuttering changes in Japanese preschool children who stutter. Thirty-three children (22 boys, 11 girls; mean age = 64.78 months) were assessed at two time points one year apart. Latent profile analysis identified a lower baseline-improved profile and a higher baseline-persistent profile, with the lower baseline-improved profile showing higher verbal working memory and inhibition performance. A multiple regression analysis showed that inhibitory control at T1 significantly predicted lower stuttering frequency at T2, even after controlling for baseline stuttering severity, receptive vocabulary, other executive function components, sex, chronological age, and intervention status. Linear mixed-effects models (LMM) showed that inhibition significantly predicted a reduction in stuttering frequency (b = -2.52, p = .005). These findings indicate the important role of inhibition in fluent speech.