Toward a unified theory of voice production and perception

Abstract

At present, two important questions about voice remain unanswered: When voice quality changes, what physiological alteration caused this change, and if a change to the voice production system occurs, what change in perceived quality can be expected? We argue that these questions can only be answered by an integrated model of voice linking production and perception, and we describe steps towards the development of such a model. Preliminary evidence in support of this approach is also presented. We conclude that development of such a model should be a priority for scientists interested in voice, to explain what physical condition(s) might underlie a given voice quality, or what voice quality might result from a specific physical configuration.

Comparing Measures of Voice Quality From Sustained Phonation and Continuous Speech

“…1 The source spectrum was then smoothed by fitting it with a four-piece model whose segments ranged from the first to the second harmonic (H1-H2), from H2 to the harmonic nearest 2 kHz (H2-2 kHz), from the harmonic nearest 2 kHz to that nearest 5 kHz (2-5 kHz), and from H2 to the harmonic nearest 5 kHz (H2-5 kHz). These segments were chosen because they capture most of the variability in source spectral shapes (Kreiman, Gerratt, & Antoñanzas-Barroso, 2007a), their individual perceptual importance has been established (Garellek, Keating, Esposito, & Kreiman, 2013;Kreiman & Garellek, 2011), and in combination, they appear to form an adequate psychoacoustic model of source contributions to voice quality (Garellek, Samlan, Gerratt, & Kreiman, 2016;Kreiman, Garellek, Chen, Alwan, & Gerratt, 2015;Kreiman, Gerratt, Garellek, Samlan, & Zhang, 2014). These measures were thus preferred to others found in the literature (jitter, shimmer, etc.)…”

Modeling the voice source in terms of spectral slopes

“…In a recent paper, Kreiman et al (2014) proposed a psychoacoustic model designed to capture the relationship between the acoustic voice signal and overall perceived voice quality. 1 Such a model is an essential component of a theory linking voice production to perception, so that when changes in the vocal production system cause changes to the acoustic signal, the acoustic changes can be used to predict the change in voice quality.…”

Perceptual evaluation of voice source models

“…The present results suggest an alternative approach: determining the spectral features of sounds that predict what listeners hear, and then seeking (and modeling) the timedomain causes of those specific spectral changes. This alternative has received little attention (but see Kreiman et al, 2014). Traditionally, spectral-domain modeling of the voice source was discouraged because it was time-consuming, yielded artifacts, and still required some temporal information, such as period length.…”

“…However, these concerns have become largely irrelevant. Computational constraints and artifacts are no longer common Kreiman et al, 2010), and much progress has been made in determining spectral parameters that vary across voices and to which listeners are sensitive (Kreiman et al, 2007a;Kreiman et al, 2014). Both approaches (modeling in the time domain vs in the spectral domain) share the goal of mapping between voice production and perception; but in the second case the functional significance of the magic moments or places is established a priori, ensuring that results will be perceptually meaningful, however complex the associations between physical and psychoacoustic events prove to be.…”

“…This paper assesses the relationship between model fit and perceptual accuracy by studying five time-domain source models (three of which are related)-the Rosenberg model (Rosenberg, 1971), the Fujisaki-Ljungqvist model (Fujisaki and Ljungqvist, 1986), the Liljencrants-Fant (LF) model (Fant et al, 1985), and two models proposed by Alwan and colleagues (Shue and Alwan, 2010;Chen et al, 2012)-and one model that describes the voice source in the spectral domain (Table I; Kreiman et al, 2014;see also Cummings and Clements, 1995). The Rosenberg model (Rosenberg, 1971), in contrast to the other models, describes the opening and closing phases of the glottal flow volume velocity with separate trigonometric functions that incorporate two timing parameters and one amplitude parameter.…”