Pitch strength of normal and dysphonic voices

Abstract

Two sounds with the same pitch may vary from each other based on saliency of their pitch sensation. This perceptual attribute is called "pitch strength." The study of voice pitch strength may be important in quantifying of normal and pathological qualities. The present study investigated how pitch strength varies across normal and dysphonic voices. A set of voices (vowel /a/) selected from the Kay Elemetrics Disordered Voice Database served as the stimuli. These stimuli demonstrated a wide range of voice quality. Ten listeners judged the pitch strength of these stimuli in an anchored magnitude estimation task. On a given trial, listeners heard three different stimuli. The first stimulus represented very low pitch strength (wide-band noise), the second stimulus consisted of the target voice and the third stimulus represented very high pitch strength (pure tone). Listeners estimated pitch strength of the target voice by positioning a continuous slider labeled with values between 0 and 1, reflecting the two anchor stimuli. Results revealed that listeners can judge pitch strength reliably in dysphonic voices. Moderate to high correlations with perceptual judgments of voice quality suggest that pitch strength may contribute to voice quality judgments.

Pitch Strength as an Outcome Measure for Treatment of Dysphonia

“…In prior research, this measure has been shown to be a good predictor of listener perception of voice quality. 17,19 As stated previously, there are two significant advantages to using a bio-inspired approach to describe changes in voices. First, this does not rely on accurate estimation of F 0 , which makes this approach applicable to the vast majority of dysphonic voices, including those classified as Type 2 or 3 signals.…”

“…Similarly, voices perceived to be more breathy were found to have lower pitch strength when compared to voices judged as being less breathy. 17 Note that the term “pitch” is not used synonymously with “fundamental frequency.” While the two are correlated, the former is a perceptual phenomenon whereas the latter is a physical property of the signal. 15 …”

Modeling of Breathy Voice Quality Using Pitch-strength Estimates

“…Over the past decade, it has been shown that the relationship between a physical stimulus (dysphonic voice sample) and its perceptual attributes are often non-linear, yet can be successfully described by analytic models that include many of the nonlinear properties of the auditory system. 11–15 For example, modeling breathiness using auditory measures derived from a loudness model 16 resulted in better correlations with perceptual data than traditional acoustic measures such as cepstral peak prominence. 12, 17 In this model, the loudness elicited by the aperiodic components in the voice was computed as “noise loudness” or NL and the loudness elicited by the harmonic energy of the vowel that is masked by the aperiodic components of the same voice was computed as “partial loudness” or PL.…”

“…15 Here pitch strength refers to how strong or faint a listener perceives the sensation of pitch in a sound stimulus. This quality is also referred to as “pitch salience.” For example, a sustained vowel like /a/ evokes a strong pitch sensation and thereby has higher pitch strength when compared to a fricative consonant like /s/.…”

“…While pitch strength has been extensively investigated in a variety of tonal and noise stimuli, 18–21 pitch strength of voices has been evaluated only recently. 15 The authors examined the reliability of listener judgments of pitch strength and the correlation between these judgments and perceptions of breathiness and roughness. The authors first established that listeners can indeed judge pitch strength in dysphonic voices (inter/intra-rater reliabilities of 0.87 and 0.80, respectively).…”