Decreased Stuttering while Walking: Speech and fMRI Findings

We present an adult case with severe persistent developmental stuttering (PDS) that improved
dramatically with simultaneous lower limb movements (LMs). During speaking with simultaneous lower
limb movement (SLM), her stuttering severity was considerably reduced. Using functional magnetic
resonance imaging (fMRI), we investigated the neural basis of speech fluency during speaking with and
without simultaneous LM. Bilateral (predominantly right) peri-rolandic cortices, supplementary motor
areas (SMA), right fusiform gyrus (FFG), and left frontal gyrus were activated in the SLM compared to
the ‘speaking only’ (S) and LM. There might be a subtype of PDS that benefits from rhythmic LMs to
improve the speech fluency. Locomotor and respiratory coupling might temporarily induce cortical timing
networks and, also induce activation, predominantly in the right hemisphere with a potential pacemaker
effect. Further investigation in larger groups is required to elucidate whether rhythmic simultaneous LMs
improve stuttering.