Research

The treatments that are available to people who stutter are limited and don’t work for everybody. There is an urgent need to develop updated treatment options that are based on our current neuroscientific understanding of stuttering. Because stuttering begins in childhood, behavioral interventions need to be developmentally appropriate for children and engaging enough to hold their attention. This project will develop a rhythm-based game and then pilot the game with children who stutter to determine whether rhythm games are a viable treatment option that can improve stuttering severity and persistence.

In collaboration with Devin McAuley, Ph.D., Professor of Cognition and Cognitive Neuroscience at Michigan State University and Say-It Labs, a therapeutic gaming company, the digital game will guide players through progressively complex rhythm training activities. The game design will apply what we have already observed through studying structural and functional connectivity in the brains of children who stutter.

Research has shown an association between deficits in the basal ganglia thalamocortical (BGTC) network and stuttering onset and persistence. The BGTC network supports timing and initiation of speech movements necessary for fluent speech. This network is also thought to play a role in enabling the brain to synchronize with rhythmic patterns in the environment to support “beat-based” timing, which relies on medial timing structures such as the putamen and the supplementary motor area. In children who stutter, behavioral deficits in beat-based timing have been observed as well as structural and functional connectivity deficits in medial timing structures. Together, this raises the question of whether a game targeted at enhancing rhythm processing and internal beat generation in children who stutter could improve these deficits, in turn supporting improved motor control and facilitating fluent speech.

Findings from developing and piloting this game are expected to build a strong foundation for breakthroughs in the development of neuroscience-guided treatments for stuttering. This is significant because it directly addresses the critical lack of effective treatment options available.

This research is funded through an NIDCD/NIH grant R01. (PI: Chang)

Many models of speech timing have proposed that speech, like other motor activities, is rhythmically structured in time. Rhythm can be defined as a pattern of durations marked by a series of events, and perceptually as the temporal organization of the physical sound pattern.  One of the hallmarks of skilled motor behavior such as fluent speech production is accurate timing, and the possible critical role of aberrant temporal processing in stuttering has been one of the oldest and most dominant perspectives in the field. However, studies examining temporal processing in children who stutter have been rare.  In our studies, we have used a rhythm perception task (auditory perceptual timing) to show that children who stutter exhibit significantly reduced rhythm discrimination performance compared to controls. The task relies on the ability to perceive the temporal organization of a sequence of tones, which taxes intrinsic timing ability (i.e., internal generation of a beat) without the confounding effects of speech production. CWS showed poorer rhythm discrimination relative to controls, especially in the complex condition where the “beats” occurring in rhythms are not explicitly marked and hence require greater internal generation of timing. In addition, CWS showed aberrant brain connectivity involving the cortico-BG networks, and a negative correlation between rhythm discrimination performance and functional connectivity of basal ganglia (BG) and cerebellum (CE). In terms of rhythm production (motor timing), the extant data are conflicting, for example based on tapping task performance in adults who stutter. Examining the relationship between  performance on temporal processing tasks and brain connectivity in the “timing networks” that involve both BG and CE circuits is expected  to provide breakthroughs in our understanding of the neurobiological bases of timing control deficits that may underlie persistent developmental stuttering. 

Combining neuroimaging and behavioral experiments that involve rhythm perception and production tasks, we are conducting parallel series of studies to investigate a novel rhythm deficit hypothesis in stuttering. This study is in collaboration with Drs. Devin McAuley at Michigan State University.

This study is funded by the NIDCD/NIH grant R01 DC011277 (PI Chang), Grammy Foundation and the RAIND (Research in Autism, Intellectual, and Neurodevelopmental Disabilities) pilot grant (PIs McAuley, Chang, Wade, Dilley).