Toronto: Children who stutter have less grey matter in key regions of the brain responsible for speech production than their non-stuttering peers, a new study has found.
The research by University of Alberta, Canada, scanned the brains of 28 children ranging from five to 12 years old. Half the children were diagnosed with stuttering; the other half served as a control.
Previous research has used MRI scans to look at structural differences between the brains of adults who stutter and those who do not.
The problem with that approach is the scans come years after the onset of stuttering, typically between the ages of two and five years, said Deryk Beal, executive director of Institute for Stuttering Treatment and Research in the Faculty of Rehabilitation Medicine at the University of Alberta.
"You can never be quite sure whether the differences in brain structure or function you're looking at were the result of a lifetime of coping with a speech disorder or whether those brain differences were there from the beginning," explained Beal, a speech-language pathologist.
The study results showed that the inferior frontal gyrus region of the brain develops abnormally in children who stutter.
This is important because that part of the brain is thought to control articulatory coding - taking information our brain understands about language and sounds and coding it into speech movements.
Beal initiated the research at the University of Toronto and completed the work upon his arrival at the University of Alberta.
He believes the results are a first step toward testing to see how grey matter volumes are influenced by stuttering treatment and understanding motor-sequence learning differences between children who stutter and those who do not.
The study was published in the journal Cortex.