Stuttering and gray matter morphometry: A population-based neuroimaging study in young children

•We explored structural brain regions in young children with a history of stuttering.•An association was observed in stuttering and auditory and speech motor regions.•Children with a history of stuttering showed less cortical volume and thickness.•These data support and add to previous structural neuroimaging findings in stuttering. Stuttering is a developmental speech disorder originating in early childhood. We aimed to replicate the association of stuttering and structural morphometry using a large, population-based prospective cohort, the Generation R Study, and explore the neurobiological mechanism of stuttering in children. Twenty-six children with a history of stuttering and 489 fluent speaking peers (ages 6–9) were included in the MRI sub-study. Cortical and subcortical regions of interest were analyzed using linear regression models. Compared to fluent speakers, children with a history of stuttering had less gray matter volume in the left inferior frontal gyrus and supplementary motor area. Exploratory surface-based brain analysis showed thinner cortex in the left inferior frontal gyrus, and in bilateral frontal and parietal areas. These findings corroborate previous studies that reported aberrant brain morphometry in speech motor and auditory regions in children who stutter. Future research is needed to explore the causal nature of this association.