title: Variability in the relationships among voice quality, harmonic amplitudes, open quotient, and glottal area waveform shape in sustained phonation.
abstract: Increases in open quotient are widely assumed to cause changes in the amplitude of the first harmonic relative to the second (H1*-H2*), which in turn correspond to increases in perceived vocal breathiness. Empirical support for these assumptions is rather limited, and reported relationships among these three descriptive levels have been variable. This study examined the empirical relationship among H1*-H2*, the glottal open quotient (OQ), and glottal area waveform skewness, measured synchronously from audio recordings and high-speed video images of the larynges of six phonetically knowledgeable, vocally healthy speakers who varied fundamental frequency and voice qualities quasi-orthogonally. Across speakers and voice qualities, OQ, the asymmetry coefficient, and fundamental frequency accounted for an average of 74% of the variance in H1*-H2*. However, analyses of individual speakers showed large differences in the strategies used to produce the same intended voice qualities. Thus, H1*-H2* can be predicted with good overall accuracy, but its relationship to phonatory characteristics appears to be speaker dependent.
authors.affiliation: Department of Head and Neck Surgery, UCLA School of Medicine, 31-24 Rehab Center, Los Angeles, California 90095-1795, USA. jkreiman@ucla.edu
authors.forename: Jody
authors.initials: J
authors.lastname: Kreiman
authors.forename: Yen-Liang
authors.initials: YL
authors.lastname: Shue
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.forename: Markus
authors.initials: M
authors.lastname: Iseli
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Gerratt
authors.forename: Juergen
authors.initials: J
authors.lastname: Neubauer
authors.forename: Abeer
authors.initials: A
authors.lastname: Alwan
mesh_terms: D001696:Biomechanical Phenomena; D005260:Female; D005931:Glottis / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D007828:Laryngoscopy; D016014:Linear Models; D008297:Male; D010699:Phonation; D010700:Phonetics; D013061:Speech Acoustics; D013068:Speech Production Measurement; D013997:Time Factors; D014741:Video Recording; D014833:Voice Quality