title: Functional and Quantitative MRI Mapping of Somatomotor Representations of Human Supralaryngeal Vocal Tract.
abstract: Speech articulation requires precise control of and coordination between the effectors of the vocal tract (e.g., lips, tongue, soft palate, and larynx). However, it is unclear how the cortex represents movements of and contact between these effectors during speech, or how these cortical responses relate to inter-regional anatomical borders. Here, we used phase-encoded fMRI to map somatomotor representations of speech articulations. Phonetically trained participants produced speech phones, progressing from front (bilabial) to back (glottal) place of articulation. Maps of cortical myelin proxies (R1 = 1/T1) further allowed us to situate functional maps with respect to anatomical borders of motor and somatosensory regions. Across participants, we found a consistent topological map of place of articulation, spanning the central sulcus and primary motor and somatosensory areas, that moved from lateral to inferior as place of articulation progressed from front to back. Phones produced at velar and glottal places of articulation activated the inferior aspect of the central sulcus, but with considerable across-subject variability. R1 maps for a subset of participants revealed that articulator maps extended posteriorly into secondary somatosensory regions. These results show consistent topological organization of cortical representations of the vocal apparatus in the context of speech behavior.
authors.affiliation: Department of Psychology, Royal Holloway, University of London, London, TW20 0EX, UK.|The Irish Longitudinal Study on Ageing, Department of Medical Gerontology, Trinity College Dublin, Dublin 2, Ireland.|Department of Psychological Sciences, Birkbeck College, University of London, Malet St, London, WC1E 7HX, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Carey
authors.affiliation: Department of Psychological Sciences, Birkbeck College, University of London, Malet St, London, WC1E 7HX, UK.|Department of Experimental Psychology, Tinbergen Building, 9 South Parks Road, Oxford, OX1 3UD, UK.
authors.forename: Saloni
authors.initials: S
authors.lastname: Krishnan
authors.affiliation: Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, 12 Queen Square, London, WC1N 3BG, UK.
authors.forename: Martina F
authors.initials: MF
authors.lastname: Callaghan
authors.affiliation: Department of Psychological Sciences, Birkbeck College, University of London, Malet St, London, WC1E 7HX, UK.|Birkbeck/UCL Centre for Neuroimaging, 26 Bedford Way, London, WC1H 0AP, UK.|Department of Experimental Psychology, UCL Division of Psychology and Language Sciences, 26 Bedford Way, London, WC1H 0AP, UK.|Department of Psychology, College of Sciences, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-4611, USA.
authors.forename: Martin I
authors.initials: MI
authors.lastname: Sereno
authors.affiliation: Department of Psychological Sciences, Birkbeck College, University of London, Malet St, London, WC1E 7HX, UK.|Birkbeck/UCL Centre for Neuroimaging, 26 Bedford Way, London, WC1H 0AP, UK.
authors.forename: Frederic
authors.initials: F
authors.lastname: Dick
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007823:Laryngeal Nerves / Q000033:anatomy & histology; D007830:Larynx; D008046:Lip / Q000294:innervation; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000033:anatomy & histology*; D010160:Palate, Soft / Q000294:innervation; D014059:Tongue / Q000294:innervation; D055815:Young Adult
keywords: MRI; mapping; somatomotor; speech; vocal tract