Recent Research and News
Results of Brain Imaging May Help Explain Why More Men Than Women Stutter
The women who stuttered had distinctly greater
connectivity between the motor and sensory
regions in both hemispheres of the brain than
the men who stuttered.
About 5 percent of children stutter. Although many leave it behind as they grow older, in adulthood, men are five times more likely than women to still stutter—for reasons that are not well understood. Intramural researchers at the NIDCD and the National Institute of Neurological Disorders and Stroke, led by Soo-Eun Chang, Ph.D., have recently used two brain imaging tools to explore sex-specific differences in brain connections that might explain the striking gender gap in persistent stuttering.
The investigators created brain maps of 18 stuttering and 14 non-stuttering volunteers using functional magnetic resonance imaging (fMRI), which shows brain areas active during speech, and diffusion tensor imaging (DTI), which provides structural information on connections between brain regions. The maps showed that, in general, people who stutter have fewer connections between the motor planning and execution areas in the left hemisphere of their brains and more connections between the right and left hemispheres in comparison with people who don’t stutter. The women who stuttered had distinctly greater connectivity between the motor and sensory regions in both hemispheres than the men who stuttered.
Dr. Chang is hoping to replicate the study in children to examine whether these brain differences are present early in life or appear later only in women who continue to stutter as adults. The preliminary findings from this research were presented at the Society for Neuroscience’s annual meeting last November. Read the abstract here (PDF).