Association Between Gray Matter Volume Variations and Energy Utilization in the Brain: Implications for Developmental Stuttering

Abstract

Purpose The biological mechanisms underlying developmental stuttering remain unclear. In a previous investigation, we showed that there is significant spatial correspondence between regional gray matter structural anomalies and the expression of genes linked to energy metabolism. In the current study, we sought to further examine the relationship between structural anomalies in the brain in children with persistent stuttering and brain regional energy metabolism. Method High-resolution structural MRI scans were acquired from 26 persistent stuttering and 44 typically developing children. Voxel-based morphometry was used to quantify the between-group gray matter volume (GMV) differences across the whole brain. Group differences in GMV were then compared with published values for the pattern of glucose metabolism measured via F 18 fluorodeoxyglucose uptake in the brains of 29 healthy volunteers using positron emission tomography. Results A significant positive correlation between GMV differences and F 18 fluorodeoxyglucose uptake was found in the left hemisphere (ρ = .36, p < .01), where speech-motor and language processing are typically localized. No such correlation was observed in the right hemisphere (ρ = .05, p = .70). Conclusions Corroborating our previous gene expression studies, the results of the current study suggest a potential connection between energy metabolism and stuttering. Brain regions with high energy utilization may be particularly vulnerable to anatomical changes associated with stuttering. Such changes may be further exacerbated when there are sharp increases in brain energy utilization, which coincides with the developmental period of rapid speech/language acquisition and the onset of stuttering during childhood. Supplemental Material https://doi.org/10.23641/asha.14110454

Stuttering: A Disorder of Energy Supply to Neurons?

“…A correlation was found for two out of four genes. Similarly, Boley et al ( 2021 ) correlated the pattern of gray matter differences with the normal pattern of cerebral glucose metabolism. A correlation of 0.36 was found for the left hemisphere.…”

Brain developmental trajectories associated with childhood stuttering persistence and recovery

“…The dopaminergic neurons have also been reported to have greater energy demands ( Pacelli et al, 2015 , Pissadaki and Bolam, 2013 ). It has been reported that brain areas with high energy demands coincide with those areas that are significantly different in brain anatomy in stuttering ( Chow et al, 2020 , Boley et al, 2021 ) (see review in Alm, ( Alm, 2021 )) and these undergo rapid growth during early childhood. The high metabolic demands in the dopamine system during dynamic periods of neurodevelopment, combined with possible deficits in connections among circuits that enable learning and execution of automatized motor sequences such as is the case in speech, may be affected in stuttering starting close to stuttering onset.…”