title: Decreased Cerebellar-Orbitofrontal Connectivity Correlates with Stuttering Severity: Whole-Brain Functional and Structural Connectivity Associations with Persistent Developmental Stuttering.
abstract: Persistent developmental stuttering is characterized by speech production disfluency and affects 1% of adults. The degree of impairment varies widely across individuals and the neural mechanisms underlying the disorder and this variability remain poorly understood. Here we elucidate compensatory mechanisms related to this variability in impairment using whole-brain functional and white matter connectivity analyses in persistent developmental stuttering. We found that people who stutter had stronger functional connectivity between cerebellum and thalamus than people with fluent speech, while stutterers with the least severe symptoms had greater functional connectivity between left cerebellum and left orbitofrontal cortex (OFC). Additionally, people who stutter had decreased functional and white matter connectivity among the perisylvian auditory, motor, and speech planning regions compared to typical speakers, but greater functional connectivity between the right basal ganglia and bilateral temporal auditory regions. Structurally, disfluency ratings were negatively correlated with white matter connections to left perisylvian regions and to the brain stem. Overall, we found increased connectivity among subcortical and reward network structures in people who stutter compared to controls. These connections were negatively correlated with stuttering severity, suggesting the involvement of cerebellum and OFC may underlie successful compensatory mechanisms by more fluent stutterers.
authors.affiliation: Program in Speech and Hearing Bioscience and Technology, Division of Medical Sciences, Harvard Medical SchoolBoston, MA, USA; McGovern Institute for Brain Research, Massachusetts Institute of TechnologyCambridge, MA, USA.
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Sitek
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of TechnologyCambridge, MA, USA; Department of Speech, Language and Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston UniversityBoston, MA, USA.
authors.forename: Shanqing
authors.initials: S
authors.lastname: Cai
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of TechnologyCambridge, MA, USA; Department of Speech, Language and Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston UniversityBoston, MA, USA; Bloorview Research Institute, Holland Bloorview Kids Rehabilitation HospitalToronto, ON, Canada; Department of Speech-Language Pathology, Faculty of Medicine, University of TorontoToronto, ON, Canada.
authors.forename: Deryk S
authors.initials: DS
authors.lastname: Beal
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of TechnologyCambridge, MA, USA; Department of Speech, Language and Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston UniversityBoston, MA, USA.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Perkell
authors.affiliation: Department of Speech, Language and Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University Boston, MA, USA.
authors.forename: Frank H
authors.initials: FH
authors.lastname: Guenther
authors.affiliation: McGovern Institute for Brain Research, Massachusetts Institute of TechnologyCambridge, MA, USA; Department of Otology and Laryngology, Harvard Medical SchoolBoston, MA, USA.
authors.forename: Satrajit S
authors.initials: SS
authors.lastname: Ghosh
keywords: MRI; connectivity; diffusion; persistent developmental stuttering; resting state