title: Lexical-perceptual integration influences sensorimotor adaptation in speech.
abstract: A combination of lexical bias and altered auditory feedback was used to investigate the influence of higher-order linguistic knowledge on the perceptual aspects of speech motor control. Subjects produced monosyllabic real words or pseudo-words containing the vowel [ε] (as in "head") under conditions of altered auditory feedback involving a decrease in vowel first formant (F1) frequency. This manipulation had the effect of making the vowel sound more similar to [I] (as in "hid"), affecting the lexical status of produced words in two Lexical-Change (LC) groups (either changing them from real words to pseudo-words: e.g., less-liss, or pseudo-words to real words: e.g., kess-kiss). Two Non-Lexical-Change (NLC) control groups underwent the same auditory feedback manipulation during the production of [ε] real- or pseudo-words, only without any resulting change in lexical status (real words to real words: e.g., mess-miss, or pseudo-words to pseudo-words: e.g., ness-niss). The results from the LC groups indicate that auditory-feedback-based speech motor learning is sensitive to the lexical status of the stimuli being produced, in that speakers tend to keep their acoustic speech outcomes within the auditory-perceptual space corresponding to the task-related side of the word/non-word boundary (real words or pseudo-words). For the NLC groups, however, no such effect of lexical status is observed.
authors.affiliation: Research Center, Sainte-Justine Hospital, Université de Montréal Montreal, QC, Canada ; School of Speech Pathology and Audiology, Université de Montréal Montreal, QC, Canada ; Centre for Research on Brain, Language and Music, McGill University Montreal, QC, Canada.
authors.forename: Nicolas J
authors.initials: NJ
authors.lastname: Bourguignon
authors.affiliation: Centre for Research on Brain, Language and Music, McGill University Montreal, QC, Canada ; School of Communication Sciences and Disorders, McGill University Montreal, QC, Canada.
authors.forename: Shari R
authors.initials: SR
authors.lastname: Baum
authors.affiliation: Research Center, Sainte-Justine Hospital, Université de Montréal Montreal, QC, Canada ; School of Speech Pathology and Audiology, Université de Montréal Montreal, QC, Canada ; Centre for Research on Brain, Language and Music, McGill University Montreal, QC, Canada.
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Shiller
keywords: altered auditory feedback; language processing; lexical effect; sensorimotor integration; speech production