title: Vocal tract and glottal function during and after vocal exercising with resonance tube and straw.
abstract: OBJECTIVE
  The present study aimed to investigate the vocal tract and glottal function during and after phonation into a tube and a stirring straw.
  
  
  METHODS
  A male classically trained singer was assessed. Computerized tomography (CT) was performed when the subject produced [a:] at comfortable speaking pitch, phonated into the resonance tube and when repeating [a:] after the exercise. Similar procedure was performed with a narrow straw after 15 minutes silence. Anatomic distances and area measures were obtained from CT midsagittal and transversal images. Acoustic, perceptual, electroglottographic (EGG), and subglottic pressure measures were also obtained.
  
  
  RESULTS
  During and after phonation into the tube or straw, the velum closed the nasal passage better, the larynx position lowered, and hypopharynx area widened. Moreover, the ratio between the inlet of the lower pharynx and the outlet of the epilaryngeal tube became larger during and after tube/straw phonation. Acoustic results revealed a stronger spectral prominence in the singer/speaker's formant cluster region after exercising. Listening test demonstrated better voice quality after straw/tube than before. Contact quotient derived from EGG decreased during both tube and straw and remained lower after exercising. Subglottic pressure increased during straw and remained somewhat higher after it.
  
  
  CONCLUSIONS
  CT and acoustic results indicated that vocal exercises with increased vocal tract impedance lead to increased vocal efficiency and economy. One of the major changes was the more prominent singer's/speaker's formant cluster. Vocal tract and glottal modifications were more prominent during and after straw exercising compared with tube phonation.
authors.affiliation: School of Communication Science and Disorders, University of Chile, Santiago, Chile. guzmanvoz@gmail.com
authors.forename: Marco
authors.initials: M
authors.lastname: Guzman
authors.forename: Anne-Maria
authors.initials: AM
authors.lastname: Laukkanen
authors.forename: Petr
authors.initials: P
authors.lastname: Krupa
authors.forename: Jaromir
authors.initials: J
authors.lastname: Horáček
authors.forename: Jan G
authors.initials: JG
authors.lastname: Švec
authors.forename: Ahmed
authors.initials: A
authors.lastname: Geneid
mesh_terms: D000162:Acoustics; D000328:Adult; D001307:Auditory Perception; D001696:Biomechanical Phenomena; D004568:Electrodiagnosis; D005260:Female; D005931:Glottis / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D007600:Judgment; D008297:Male; D010699:Phonation; D011312:Pressure; D063346:Singing; D013018:Sound Spectrography; D036542:Tomography, Spiral Computed; D014827:Vocal Cords / Q000000981:diagnostic imaging / Q000502:physiology*; D014833:Voice Quality; D014834:Voice Training