Previous studies have shown that adults who stutter
produce smaller corrective motor responses
to compensate for unexpected auditory perturbations in comparison to adults who do not stutter, suggesting that stuttering may be associated with deficits in integration of auditory feedback for
online speech monitoring. In this study, we examined whether stuttering is also associated with
deficiencies in integrating and using discrepancies between expect
ed and received auditory
feedback to adaptively update motor programs for accurate speech production.
Using a sensorimotor adaptation paradigm, we measured adaptive speech responses to auditory formant frequency perturbations in adults and children who stutter and their matched nonstuttering
controls.
We found that the magnitude of the speech adaptive response for children who stutter
did not differ from that of fluent children. However, the adaptation magnitude of adults who
stutter in response to formant
perturbation was significantly smaller than the adaptation
magnitude of adults who do not stutter. Together these results indicate that stuttering is
associated with deficits in integrating discrepancies between predicted and received auditory feedback to calibrate the speech production system in adults but not children. This auditory-motor integration deficit thus appears to be a compensatory effect that develops over years of stuttering