The neural correlates of developmental stuttering

A brief overview of the literature

Abstract

Developmental stuttering (DS) is a disruption of the rhythmic flow of speech, and its aetiology is still obscure. Neuroimaging/neurophysiological techniques have been used to study, the neural system of people with DS highlighting the presence of widespread structural/ functional abnormalities, especially in the motor system. Reduced white matter integrity and altered functioning of the basal ganglia-thalamo-cortical circuit play a key role in DS. Evidence from transcranial magnetic stimulation suggests the presence of an altered interplay between excitatory and inhibitory signals, especially in the left motor cortices; findings of neurophysiological indexes obtained from non-speech related muscles, support the theory that stuttering is the overt symptom of a more general motor disorder. Further investigations need to be conducted to better elucidate the neural basis of this disorder, in order to find better rehabilitative solutions.