title: Speech-induced suppression of evoked auditory fields in children who stutter.
abstract: Auditory responses to speech sounds that are self-initiated are suppressed compared to responses to the same speech sounds during passive listening. This phenomenon is referred to as speech-induced suppression, a potentially important feedback-mediated speech-motor control process. In an earlier study, we found that both adults who do and do not stutter demonstrated a reduced amplitude of the auditory M50 and M100 responses to speech during active production relative to passive listening. It is unknown if auditory responses to self-initiated speech-motor acts are suppressed in children or if the phenomenon differs between children who do and do not stutter. As stuttering is a developmental speech disorder, examining speech-induced suppression in children may identify possible neural differences underlying stuttering close to its time of onset. We used magnetoencephalography to determine the presence of speech-induced suppression in children and to characterize the properties of speech-induced suppression in children who stutter. We examined the auditory M50 as this was the earliest robust response reproducible across our child participants and the most likely to reflect a motor-to-auditory relation. Both children who do and do not stutter demonstrated speech-induced suppression of the auditory M50. However, children who stutter had a delayed auditory M50 peak latency to vowel sounds compared to children who do not stutter indicating a possible deficiency in their ability to efficiently integrate auditory speech information for the purpose of establishing neural representations of speech sounds.
authors.affiliation: Department of Speech-Language Pathology, University of Toronto, Toronto, Ontario, Canada. d.beal@utoronto.ca
authors.forename: Deryk S
authors.initials: DS
authors.lastname: Beal
authors.forename: Maher A
authors.initials: MA
authors.lastname: Quraan
authors.forename: Douglas O
authors.initials: DO
authors.lastname: Cheyne
authors.forename: Margot J
authors.initials: MJ
authors.lastname: Taylor
authors.forename: Vincent L
authors.initials: VL
authors.lastname: Gracco
authors.forename: Luc F
authors.initials: LF
authors.lastname: De Nil
mesh_terms: D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D002648:Child; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D013060:Speech / Q000502:physiology*; D013342:Stuttering / Q000503:physiopathology*