Persistent developmental stuttering is a speech disorder that affects ~1% of the general population and is notoriously difficult to treat, often with life-long psychosocial and emotional consequences. In adults who stutter, approximately 50% report debilitating social anxiety disorder. While negative emotional reactions commonly result from persistent stuttering, theoretical models suggest that heightened levels of anxiety in children close to symptom onset may predict persistent stuttering. Whether anxiety and stuttering in young children share common underlying mechanisms remains unknown, but a cumulative body of research suggests that abnormal brain response to errors may drive both processes. Building from this research, we will test early anxiety and a neurophysiological index of error-processing, the ?error-related negativity? (ERN), as predictors of persistent stuttering at one-year follow-up in young children who stutter. The proposed research considers the established relationship of ERN with anxiety, in the context of ?vicious cycle? model of stuttering that posits hypersensitivity to speech-errors drives stuttering disfluency. Extending this model, we suggest that early anxiety, together with age-related increases in stuttering awareness in young children, increase reactivity of the error-monitoring system, leading to persistent speech difficulties. To test this hypothesis, we will collect a detailed speech-language assessment, clinical measures of anxiety and ERN in thirty 3.5-6.0 year old preschoolers who stutter and twenty controls during an error-eliciting cognitive task, designed for young children. Ultimately, we expect that the successful completion of this research will position us to submit an R01 application to the National Institute on Deafness and Other Communication Disorders to establish clinically informed, mechanism-based biomarkers of the course of early stuttering that, ultimately, will guide the identification of children at highest risk for persistent symptoms and serve as targets for novel interventions to prevent chronic stuttering.
Stuttering affects up to five percent of preschool-aged children worldwide. The successful completion of this pilot project will lead to an improved understanding of the brain mechanisms underlying the relationship between anxiety and stuttering, and establish clinically informed, mechanism-based biomarkers of early stuttering course to guide the identification of children at highest risk for persistent symptoms.
