title: Onset sequencing of selected lip muscles in stutterers and nonstutterers.
abstract: The present study examined lip muscle activity during the speech production of stutterers and fluent speakers to provide information about the nature of stuttering blocks. Depressor Anguli Oris (DAO) and Depressor Labii Inferioris (DLI) were recorded, using hooked-wire electromyography (EMG), in 3 stutterers and 3 nonstutterers during productions of the words "peek", "puck", and "pack." EMG records indicated that nonstutterers activated DAO prior to DLI for production of the initial/p/. Stutterers frequently reversed this sequence of onset, particularly when they stuttered. Results are discussed in terms of mistiming versus anticipatory hypertension hypotheses about stuttering.
authors.affiliation: University of Vermont, Communication Science & Disorders, Burlington 05405.
authors.forename: B
authors.initials: B
authors.lastname: Guitar
authors.forename: C
authors.initials: C
authors.lastname: Guitar
authors.forename: P
authors.initials: P
authors.lastname: Neilson
authors.forename: N
authors.initials: N
authors.lastname: O'Dwyer
authors.forename: G
authors.initials: G
authors.lastname: Andrews
mesh_terms: D004576:Electromyography; D005152:Facial Muscles / Q000503:physiopathology*; D006801:Humans; D008046:Lip / Q000503:physiopathology*; D008297:Male; D008959:Models, Neurological; D013060:Speech / Q000502:physiology; D013342:Stuttering / Q000503:physiopathology*; D013997:Time Factors