title: Interspeaker variability in hard palate morphology and vowel production.
abstract: OBJECTIVE
  Differences in vocal tract morphology have the potential to explain interspeaker variability in speech production. The potential acoustic impact of hard palate shape was examined in simulation, in addition to the interplay among morphology, articulation, and acoustics in real vowel production data.
  
  
  METHODS
  High-front vowel production from 5 speakers of American English was examined using midsagittal real-time magnetic resonance imaging data with synchronized audio. Relationships among hard palate morphology, tongue shaping, and formant frequencies were analyzed. Simulations were performed to determine the acoustical properties of vocal tracts whose area functions are altered according to prominent hard palate variations.
  
  
  RESULTS
  Simulations revealed that altering the height and position of the palatal dome alters formant frequencies. Examinations of real speech data showed that palatal morphology is not significantly correlated with any formant frequency but is correlated with major aspects of lingual articulation.
  
  
  CONCLUSIONS
  Certain differences in hard palate morphology can substantially affect vowel acoustics, but those effects are not noticeable in real speech. Speakers adapt their lingual articulation to accommodate palate shape differences with the potential to substantially affect formant frequencies, while ignoring palate shape differences with relatively little acoustic impact, lending support for acoustic goals of vowel production.
authors.forename: Adam
authors.initials: A
authors.lastname: Lammert
authors.forename: Michael
authors.initials: M
authors.lastname: Proctor
authors.forename: Shrikanth
authors.initials: S
authors.lastname: Narayanan
mesh_terms: D003198:Computer Simulation; D004525:Efferent Pathways / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D021362:Palate, Hard / Q000033:anatomy & histology* / Q000502:physiology*; D010700:Phonetics; D013060:Speech / Q000502:physiology*; D013061:Speech Acoustics; D013068:Speech Production Measurement; D014059:Tongue / Q000294:innervation / Q000502:physiology; D014827:Vocal Cords / Q000294:innervation / Q000502:physiology