Acoustic Correlates of Breathy Vocal Quality: Dysphonic Voices and Continuous Speech

Abstract

In an earlier study, we evaluated the effectiveness of several acoustic measures in predicting breathiness ratings for sustained vowels spoken by nonpathological talkers who were asked to produce nonbreathy, moderately breathy, and very breathy phonation (Hillenbrand, Cleveland, & Erickson, 1994). The purpose of the present study was to extend these results to speakers with laryngeal pathologies and to conduct tests using connected speech in addition to sustained vowels. Breathiness ratings were obtained from a sustained vowel and a 12-word sentence spoken by 20 pathological and 5 nonpathological talkers. Acoustic measures were made of (a) signal periodicity, (b) first harmonic amplitude, and (c) spectral tilt. For the sustained vowels, a frequency domain measure of periodicity provided the most accurate predictions of perceived breathiness, accounting for 92% of the variance in breathiness ratings. The relative amplitude of the first harmonic and two measures of spectral tilt correlated moderately with breathiness ratings. For the sentences, both signal periodicity and spectral tilt provided accurate predictions of breathiness ratings, accounting for 70%-85% of the variance.

Measures of the Glottal Source Spectrum

“…1 Inharmonic (noise) energy also contributes significant excitation (e.g., Hillenbrand & Houde, 1996), particularly in female voices in which persistent glottal gaps may be present (e.g., Holmberg, Hillman, Perkell, Guiod, & Goldman, 1995;Linville & Fisher, 1992), in male or female "sexy" voice (Henton & Bladon, 1985), and in pathologic phonation. For example, Holmberg et al found that for women with normal voice, most vowel productions displayed a mix of harmonic energy and noise in the F3 region; some showed mostly noise, and only a few tokens were produced with predominantly harmonic energy.…”

Acoustic "breathiness measures" in the description of pathologic voices

“…This is in accordance with the assumption that a poor glottal closure leads to a stronger attenuation of the harmonics [3,10]. On the other hand, the mean of the aphonic group (-8.4dB) can be interpreted as indication of the spectral shape of the noise excitation.…”

“…On the other hand, the mean of the aphonic group (-8.4dB) can be interpreted as indication of the spectral shape of the noise excitation. This noise can be described as bandpass-filtered white noise [10], so that the negative value reflects the attenuation of low-frequent spectral energy. However, the transition from highly disturbed voices that still exhibit a harmonic structure (e.g., aep) to complete aphonia remains unclear.…”

“…Since many researchers regard "breathiness" as being caused by glottal air leakage [1,4], acoustic measures of breathiness may serve as a pool supplying useful candidates in the assessment of glottal closure. The "breathiness measure" most commonly encountered is the already mentioned H1H2 [3,[9][10][11]13]. Additionally, de Krom determined the harmonics to noise ratio (HNR) and several measures of the spectral slope as -somewhat ambiguous -best correlates of breathiness in a thorough study on the relation between acoustic measures and perceptual voice attributes [3].…”

The Nationwide Speech Project: A new corpus of American English dialects

“…The Rainbow Passage has been used in a variety of acoustic and perceptual studies of speech, including investigations of talker differences (e.g., Gelfer and Schofield, 2000) and the speech of clinical populations (e.g., Baker et al, 1997;Hillenbrand and Houde, 1996;McHenry, 1999;Sapienza et al, 1999).…”