Impact of Instructed Laryngeal Manipulation on Acoustic Measures of Voice-Preliminary Results

Connecting Auditory-Perceptual Prompts Used in Voice Therapy to Anatomy and Physiology: Application to the Estill Voice Model and the Rehabilitation Treatment Specification System

PURPOSE

This clinical tutorial will present the concept of applying auditory-perceptual prompts (implicit instruction) typically used in voice therapy to the anatomy and physiology of the voice production system (explicit instruction) via the Estill Voice Model (EVM) and the Rehabilitation Treatment Specification System (RTSS).

METHODS

EVM offers an integrated implicit-explicit instructional approach to voice training allowing for isolated practice of vocal structures (explicit) that interact to produce functional voice qualities (implicit), such as modal speech and louder projected voice qualities. In EVM, voice quality is correlated with the specific anatomy and physiologic adjustments via 13 Estill Figures and Options (eg, Larynx Figure has three options: High, Mid, and Low). RTSS provides a framework to connect client change in functioning (ie, target) with clinician action (ie, ingredients). Mechanisms of action connect the target to the ingredients by hypothesizing how the treatment is expected to work.

RESULTS

Evidence is provided for connecting auditory-perpetual voice prompts with the anatomy and physiology of voice and supporting an integrated implicit-explicit approach to voice therapy. The concept of linking commonly used implicit auditory-perceptual prompts used in voice therapy (eg, humming, loud "aahh") to explicit anatomy and physiology training (eg, 13 Estill Figures and Options) is demonstrated using EVM and the RTSS framework with case studies and video examples.

CONCLUSIONS

Clinicians may choose to use anatomy and physiology of voice to define and provide explicit instruction for typically used implicit auditory-perceptual prompts. Future research is warranted to test the concept applied to voice therapy models in the literature across prevention and treatment of voice disorders.

Auditory-perceptual Parameters as Predictors of Voice Acoustic Measures

BACKGROUND

Much research has examined the relationship between perceptual and acoustic measures. However, little is known about the prediction values of perceptual measures on an acoustic parameter.

AIMS

This study utilized simulated and disordered voice samples to investigate the prediction values of breathiness, roughness, and strain ratings on the selection of some time-based and spectral-based measures of voice quality.

METHOD

This study retrospectively analysed two sets of precollected data. The experimental data had been collected from nine trained speakers manipulating false vocal fold activity, true vocal fold mass, and larynx height. The voice-disordered data had been extracted from a clinical database for 68 patients with muscle tension voice disorders (MTVD). Both data sets had been perceptually rated for breathiness, roughness, and strain. Voice samples (prolonged vowel /ɑ/ and Rainbow Passage readings) had undergone acoustic analysis using Praat for harmonics-to-noise ratio (HNR) and the program "Analysis of Dysphonia in Speech and Voice" (ADSV) for cepstral peak prominence (CPP), Cepstral/Spectral Index of Dysphonia (CSID), and Low/High spectral ratio (L/H ratio). Perceptual parameters were regressed against these acoustic measures to test their prediction values.

RESULTS

Reliability data showed satisfactory intra- and inter-reliability of perceptual ratings for both data sets. Breathiness significantly predicted CPP (both vocal tasks) and CSID (Rainbow Passage) in experimental data and predicted all the acoustic measures in MTVD data. Roughness significantly predicted HNR, CPP, and CSID in experimental data, and CPP (Rainbow Passage) and CSID (both vocal tasks) in MTVD data. Strain (both vocal tasks) significantly predicted L/H ratio in both data sets.

CONCLUSIONS

Breathiness ratings predicted selection of HNR, CPP and CSID; roughness ratings predicted selection of CPP and CSID, and strain ratings predicted L/H ratio.

Development and Validation of a Single-Variable Comparison Stimulus for Matching Strained Voice Quality Using a Psychoacoustic Framework

PURPOSE

Acoustic and perceptual quantification of vocal strain has been a vexing problem for years. To increase measurement rigor, a suitable single-variable matching stimulus for strain was developed and validated, based on the matching stimulus used previously for breathy and rough voice qualities.

METHOD

A set of 21 comparison stimuli for a single-variable matching task (SVMT) was synthesized based on a speech-shaped sawtooth waveform mixed with speech-shaped noise. Variable bandpass filter gain in mid-to-high frequencies achieved a wide range of computed sharpness (in constant sharpness steps) and served as the independent variable for the SVMT. Ten natural /ɑ/ stimuli with a wide range of the primary voice quality of strain and a minimum of breathiness or roughness were selected and assessed using the SVMT. Natural voice samples and synthetic comparison stimuli were also assessed using a perceptual magnitude estimation (ME) task.

RESULTS

ME data validated the correspondence of the set of comparison stimuli to varying perceived strain. Perceived strain magnitudes of the comparison stimuli increased significantly and linearly with computed sharpness (r ² = .99). A linear regression revealed that strain matching values were significantly predicted by computed sharpness (r ² = .96) and perceived strain magnitudes (r ² = .95) of the natural voice stimuli.

CONCLUSION

The perception of vocal strain is strongly associated with computed sharpness and is captured accurately and precisely using an SVMT, in which the independent variable is the bandpass filter gain (in steps of equal sharpness) applied to the comparison stimuli.

The Immediate and Long-Term Effects of Tube and Mask+Tube Phonation in Water Exercises and Their Duration as Measured by Electroglottographic and Nasometric Parameters

OBJECTIVE

This study investigated the immediate effects and their persistence (at 15 minutes) of various durations of semi-occluded vocal tract exercise (SOVTE) (standard tube into water and modified mask+tube into water exercises) as measured by electroglottographic (EGG) and nasometric parameters.

METHODS

The study included 30 women aged 19 through 28 years with healthy voices, and it comprised five randomly implemented procedures (Ps): P1-tube phonation into water for 5 minutes; P2-tube phonation into water for 10 minutes; P3-tube+ventilation mask phonation into water for 5 minutes; P4-tube+ventilation mask phonation into water for 10 minutes; P5-phonation with ventilation mask for 5 minutes. Fifteen-minute voice rest breaks were provided between each procedure. Nasometric and electroglottographic measurements were taken before, during, immediately after and at 5, 10, and 15 minutes after the exercises, and the recorded measurements were analyzed.

RESULTS

The immediate effects of P3 and P4 on voice quality showed better performance than the other procedures. Among all the procedures, P1 had the smallest effect on voice quality in terms of nasometric and EGG parameters and the least degree of effect permanence. In all the fluctuating SOVTE procedures except P1, the nasalance scores decreased (P1, P2, P3, and P4: fluctuating SOVTE; P5: steady SOVTE).

CONCLUSION

The tube phonation exercises modified by the addition of a ventilation mask were highly advantageous in terms of EGG parameters. In addition to this, regardless of the mode of application of the retention time, it was observed that the positive effect (ie, lower vertical laryngeal position) of the exercises applied for 10 minutes was higher than the exercises applied for 5 minutes.