title: Human vocal tract resonances and the corresponding mode shapes investigated by three-dimensional finite-element modelling based on CT measurement.
abstract: Resonance frequencies of the vocal tract have traditionally been modelled using one-dimensional models. These cannot accurately represent the events in the frequency region of the formant cluster around 2.5-4.5 kHz, however. Here, the vocal tract resonance frequencies and their mode shapes are studied using a three-dimensional finite element model obtained from computed tomography measurements of a subject phonating on vowel [a:]. Instead of the traditional five, up to eight resonance frequencies of the vocal tract were found below the prominent antiresonance around 4.7 kHz. The three extra resonances were found to correspond to modes which were axially asymmetric and involved the piriform sinuses, valleculae, and transverse vibrations in the oral cavity. The results therefore suggest that the phenomenon of speaker's and singer's formant clustering may be more complex than originally thought.
authors.affiliation: Faculty of Mechanical Engineering, Czech Technical University in Prague, Department of Mechanics, Biomechanics and Mechatronics , Technická 4, Prague 6, Prague, 16607 Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Vampola
authors.forename: Jaromír
authors.initials: J
authors.lastname: Horáček
authors.forename: Anne-Maria
authors.initials: AM
authors.lastname: Laukkanen
authors.forename: Jan G
authors.initials: JG
authors.lastname: Švec
mesh_terms: D000162:Acoustics; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D005260:Female; D020342:Finite Element Analysis; D005931:Glottis / Q000000981:diagnostic imaging* / Q000502:physiology*; D006801:Humans; D008953:Models, Anatomic; D008954:Models, Biological; D009716:Numerical Analysis, Computer-Assisted; D010699:Phonation; D011312:Pressure; D011857:Radiographic Image Interpretation, Computer-Assisted; D013018:Sound Spectrography; D013061:Speech Acoustics; D013068:Speech Production Measurement; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014732:Vibration; D014833:Voice Quality
keywords: Acoustic mode shapes of vibration; biomechanics of human voice; speaker's and singer's formant; voice production modelling