Linguistic Processing and Reaction Time Differences in Stutterers and Nonstutterers

Abstract

Linguistic processing by the left and right cerebral hemispheres was investigated in 10 adult male stutterers and l0 matched nonstutterers. Subjects performed a lexical decision task in which nonword and real-word stimuli were presented tachistoscopically to the right and left visual hemifields. Vocal and manual reaction times to real words were measured to assess hemispheric participation in processing linguistic information and to determine differences between response modes. The stuttering group exhibited a left visual field efficiency or right hemisphere preference for this task and were slower in both vocal and manual reaction times. Ramifications for hemispheric processing theories and laryngeal dysfunction hypothesis are discussed.

Phonological encoding in the silent speech of persons who stutter

“…This may seem somewhat inconsistent with the main conclusion of a phonological encoding deficit in stuttering speakers because phonological encoding is involved in naming. There is some limited evidence of lexical access differences between stuttering and nonstuttering speakers (Hand & Haynes, 1983;Rastatter & Dell, 1987). It is possible that the naming practice involved in the familiarization task in the present study may have facilitated initial lexical access, thereby minimizing any existing betweengroup differences in picture naming.…”

Effects of word frequency and phonological neighborhood characteristics on confrontation naming in children who stutter and normally fluent peers

“…Adults who stutter (AWS) are slower to decide whether an item is a word in the language than are adults who do not stutter (Hand & Haynes, 1983;Rastatter & Dell, 1987). They are also slower to name pictures, even when the stimuli consist of as few as eight familiar nouns and verbs that had been previously pretested to assure their recognition (Prins et al, 1997).…”

Asymmetries in mouth opening during word generation in male stuttering and non-stuttering participants

“…A range of behavioural methods have been used to infer hemispheric activity in people who stutter in response to auditory and visual stimuli; for example, dichotic listening (Blood, 1985;Curry & Gregory, 1969;Rosenfield & Goodglass, 1980;Sommers, Brady, & Moore, 1975; see Code, 1998a, for review) and tachistoscopic viewing (Hand & Haynes, 1983;Moore, 1976;Szelag, Garwarska-Kolek, Herman, & Stasiek, 1993). More recently a range of neural imaging studies have been conducted using Positron Emission Tomography (PET), Single-Positron Emission Computerised Tomography (SPECT), and Functional Magnetic Resonance Imaging (fMRI) to examine activation in the brains of people who stutter (Ingham, 2001;Ingham et al, 1996;Ingham, Ingham, Finn, & Fox, 2003;Pool, Devous, Freeman, Watson, & Finitzo, 1991;Watson, Freeman, Devous, Chapman, Finitzo, & Pool, 1994).…”