Immediate Effects of Humming on Computed Electroglottographic Parameters in Patients With Muscle Tension Dysphonia

Assessing the Effectiveness of Voice Therapy Techniques in Treating Dysphonia: An Otolaryngological Review

Dysphonia is a prevalent condition that can impact individuals across all age groups. It occurs when normal voice quality is altered, caused by structural and/or functional issues. Evaluation and assessment from clinicians are warranted if dysphonia persists for more than four weeks and/or is coupled with risk factors or other concerning clinical manifestations. Additionally, voice disorders can increase the risk of depression and anxiety disorders, as well as raise stress levels and lower self-reported health indicators. Dysphonia can have a substantial influence on interpersonal interactions and lower overall quality of life since effective communication relies significantly on spoken language. Hence, managing dysphonia is essential for enhancing communication abilities, improving quality of life, maintaining vocational functioning, promoting psychological well-being, and addressing underlying health concerns. Speech and language therapy, medical management, surgery, or a combination of the aforementioned are all possible treatments for dysphonia. Speech and language therapy is often the first-line treatment option for dysphonia patients who do not meet the criteria for surgical intervention. Voice therapy is often beneficial and remains the first line of treatment, even when patients approach with benign vocal fold nodules. A well-designed voice therapy program improves both the quality of life and vocal performance. The majority of the studies in the existing literature advocate for and report beneficial outcomes associated with voice therapy; however, more research is needed to provide evidence-based findings to guide clinical practice and achieve optimal outcomes. This comprehensive review elaborately highlights the utilization and efficacy of various voice therapeutic modalities utilized for the management of dysphonia in light of current literature.

Immediate and Short-term Effects of Straw Phonation in Air or Water on Vocal Fold Vibration and Supraglottic Activity of Adult Patients with Voice Disorders Visualized with Strobovideolaryngoscopy: A Pilot Study

Purpose The first purpose of this study was to investigate and compare the short-term effects after a semi-occluded vocal tract (SOVT) therapy session consisting of straw phonation (SP) in air or water on vocal fold vibration and supraglottic activity of adult patients with voice disorders, visualized with strobovideolaryngoscopy (SVL). The second purpose of this study was to investigate and compare immediate changes in the patients' vocal fold vibration and supraglottic activity during SP in air or water, visualized with SVL. Methods Twelve adult patients with voice disorders (eight women and four men, mean age 52 years) were assigned randomly to one of two study groups: SP in air or SP in water. Immediately before and after a therapy session of 15 min, participants underwent a rigid SVL to determine the short-term effects of the SP session. At the posttherapy examination, flexible SVL while performing SP was added to determine the effects occurring during SP. The visual-perceptual ratings were performed blindly and in random order by three laryngologists, using the Voice-Vibratory Assessment with Laryngeal Imaging rating form for stroboscopy. ResultsShort-term effects after SP: After the SP-in-air session, the supraglottic mediolateral compression decreased significantly. The SP-in-water session led to significantly increased left vibrational amplitude. Immediate effects during SP: During SP in air, a significantly increased left amplitude and mucosal wave, and significantly decreased mediolateral supraglottic activity, were found. SP in water tended to decrease the vibrational amplitude during performance of the task. A trend toward higher anteroposterior supraglottic compression was observed during both SP in air and water, being more prominent in the latter. Conclusion SP in air led to less false vocal fold adduction and consequently less hyperfunction. The small increment in anteroposterior supraglottic activity during SP in air and water might be related to epilarynx narrowing, an economic phenomenon associated with SOVT exercises. The effects on vibrational amplitude were rather ambiguous. The small reduction in amplitude during SP in water is expected to diminish vocal fold impact stress and therefore creates an ideal basis for voice therapy. The increment in amplitude and mucosal wave during SP in air might indicate insufficient supraglottic pressure to obtain the favorable effects of semi-occlusion. Whether or not the rise in amplitude after the SP-in-water session is due to voice efficiency or voice fatigue remains unknown. Future larger-scale investigation in subgroups of voice patients is needed to explore these hypotheses.

An eclectic Voice Therapy Program for the Treatment of Hyperfunctional Voice Disorders (HFVD)

PURPOSE

An eclectic voice therapy program includes sequenced and structured set of exercises combining direct and indirect intervention methods. Tailor-made exercise prescription with specific cultural adaptations are needed to provide a holistic change to voice quality.1 This study detailed the construction of an exercise prescription for participants with hyperfunctional voice disorder [HFVD] in the Indian context.

METHOD

The exercise program was developed based on literature related to vocal therapy approaches and delivery methods. Adaptations were introduced to a selected set of exercises. Five voice experts verified the exercises and their prescription for content and feasibility of use in the Indian context. Modification suggested by the experts were included for framing the final version of the exercise program. This structured therapy program was planned for 6 weeks (30 minutes duration/session offered individually twice per week, with a gap of two days between sessions in a week) with the goals to improve voice quality, flexibility, and endurance while speaking. Five participants with HFVD partook in the study for pilot testing. Stroboscopy, perceptual voice analysis, Dysphonia Severity Index (DSI) and Vocal Fatigue Index in Tamil (VFI-T) were used to report the therapy outcomes. Participants' report on the learning process and generalization of the program were documented. Wilcoxon-signed rank test was used to test the pre-post outcome measures.

RESULTS

An eclectic voice therapy program, i.e., Comprehensive Voice Habilitation Program [CVHP] was constructed and it included vocal hygiene instructions, warm-up & cool-down, easy onset, resonant voice, and carry over exercises. Participants completed the program in 14-18 sessions (over 7 to 9 weeks of therapy). All participants showed significant changes in vocal fold movement patterns, reduction in ventricular hyperadduction, overall grade of voice quality, DSI and VFI-T. Participants reported that pictorial illustrations, feedback, and monitoring sheets were useful in learning the exercises.

CONCLUSION

CVHP showed significant change in the voice-related outcome measures and was a viable program for treating HFVD.

Semi-occluded Nasal Tract Exercises (SONTEs): Nasal Tube in Water Exercises Using Nasal Consonants

OBJECTIVE

This study analyzes the effects of the vocal exercises called semi-occluded nasal tract exercises (SONTEs), which were carried out with a new appliance that extends the nasal cavity as a part of the vocal tract. The acoustic, aerodynamic and electroglottographic (EGG) measurements were compared with those of the traditional semi-occluded vocal tract exercises (SOVTEs) of phonation in water.

METHODS

In this study, 34 women were randomly asked to perform phonation in water for 5 min through the nasal and oral routes with the sounds /m/ and /ɔ/, respectively, using a tube with a submersion depth of 5 cm. The acoustic, aerodynamic and EGG measurements before and after the exercises were analyzed using the appropriate statistical methods.

RESULTS

No significant difference was found in the time and frequency domain parameters before and after the exercises, except for the amplitude perturbation quotient (APQ) values, which decreased after both exercises. In addition, there was no significant difference in any aerodynamic parameters before and after the exercises, but the mean SPL values significantly increased after both exercises. The oral and nasal peak inspiratory flow rates increased after both exercises, but the increase peaked after the SONTEs implementation. As expected, the EGG-jitter and EGG-periodicity values had a reciprocal interaction with each other, while differences were observed between the values of the vocal fold movements measured in both exercises.

CONCLUSIONS

SONTEs may be as effective as the conventional SOVTEs because it made tube phonation into water possible through artificial extension of the nasal cavity and increased the resonant effect by using the positive effects based on the principles of SOVTEs.

Acoustic Description of Bhramari Pranayama

The study's aim was (1) To describe the acoustic characteristics of Bhramari pranayama, and (2) to compare the acoustic features of nasal consonant /m/ and the sound of Bhramari pranayama produced by yoga trainers. Cross-sectional study design. Thirty-three adult male yoga trainers performed five repeats of nasal consonant /m/ and Bhramari pranayama. These samples were recorded into Computerized Speech Lab, Kay Pentax model 4500b using a microphone (SM48). Formant frequencies (f F1, f F2, f F3, & f F4), formant bandwidths (BF1, BF2, BF3, & BF4), anti-formant, alpha and beta ratio were analyzed. Nasal consonant /m/ had higher f F2 and anti-formant compared to Bhramari pranayama. Statistical significant differences were noted in f F2, BF3, and anti-formants. Bhramari pranayama revealed a low alpha ratio and a higher beta ratio than /m/. However, these differences were not statistically significant. Findings are discussed from acoustic and physiological perspectives. Bhramari pranayama was assumed to be produced with a larger pharyngeal cavity and narrower velar passage when compared to nasal consonant /m/. Verification at the level of the glottis and with aerodynamic parameters may ascertain the above propositions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-021-03054-1.

Symptom Expression Across Voiced Speech Sounds in Adductor Laryngeal Dystonia

OBJECTIVES

Differential diagnosis for adductor laryngeal dystonia (AdLD) is often carried out by comparing symptom expression during sentences with either all voiced or voiced and voiceless consonants. However, empirical research examining the effects of phonetic context on symptoms is sparse. The purpose of this study was to examine whether symptom probabilities varied across voiced speech segments in an all-voiced sentence, and whether this variability was systematic with respect to phonetic features.

METHODS

Eighteen speakers with AdLD read aloud a sentence comprised entirely of voiced speech sounds. Speech segment boundaries and AdLD symptoms (phonatory breaks, frequency shifts, and creak) were labeled separately, and speech segments were coded as symptomatic or asymptomatic based on their temporal overlap. Generalized linear mixed effects models with a binomial outcome variable were used to compare the probability of symptom expression across: 1) all speech segments in the sentence, and 2) four speech sound classes (vowels, approximants, nasals, and obstruents).

RESULTS

Significant symptom variability was found across voiced speech segments in the sentence. Furthermore, the estimated probability of a symptom occurring on vowels and approximants was significantly greater than that of nasals and obstruents.

CONCLUSION

These results indicate that AdLD symptoms are not uniformly distributed across voiced speech segments with systematic variation across speech sound classes.To explain these findings, future work should investigate how the complex interactions between the vocal tract articulators and glottal configurations may influence symptom expression in this population.

Do Professionals Who Use the Voice in a Journalistic Context Benefit from Humming as a Semi-occluded Vocal Tract Exercise?

INTRODUCTION

Many vocal enhancement and rehabilitation programs for voice professionals define vocal exercises without analyzing their effects on that specific population in which they will be applied, in the established dose and often without considering the presence and absence of vocal alteration. Journalists have sought the voice clinic due to new professional vocal demands and a vocal program is being elaborated.

OBJECTIVE

To determine the immediate effect of humming in professionals with and without voice disorders who work under high vocal demand in a journalistic context.

METHOD

Thirty-six individuals who completed the Dysphonia Risk Screening Protocol and underwent voice recording participated in the study. Three speech therapists defined the presence and/or absence of vocal changes by consensus. Subsequently, five repetitions of humming were proposed; the exercises lasted five seconds each and were separated by five seconds of complete silence, and recordings were made before and after the exercise (vowel and phrase). For the pre and post comparison between the groups with and without vocal changes, acoustic measurements and spectrogram, including the classification of the signal type, were performed.

RESULTS

The sample had a similar distribution of men and women and a mean age of 39.9 years. Most of the professionals were journalists or reporters. The risk of dysphonia was high for half of the sample, and the presence of vocal changes, predominantly mild ones, was identified in 56%. After the exercise, a decrease in noise at low frequencies and an improvement in the series of harmonics and the signal type were observed in both groups; a decrease in irregularity was observed only in the participants without vocal changes.

CONCLUSION

The proposed humming exercise had an immediate positive effect on the voice of professionals working in a journalistic context, and the changes were particularly evident in aspects of the voice that were initially altered.

The Impact of Nasalance on Cepstral Peak Prominence and Harmonics-to-Noise Ratio

Objectives/Hypothesis

Cepstral peak prominence (CPP) has been reported as a reliable measure of dysphonia and a preferred alternative to harmonics‐to‐noise ratio (HNR). However, CPP has been observed to be sensitive to articulatory variation and vocal intensity. The aim of this study was to examine the impact of nasalance on CPP and HNR of voice signals. It was hypothesized that increased nasalance would be associated with decreased CPP.

Study Design

Within‐subject correlation design.

Methods

Thirty vocally healthy female participants were recorded reading and producing a vowel in alternation with a nasal consonant while wearing a nasometer for calculation of nasalance. Recorded vowel, nasalized, and nasal segments of speech were used to calculate CPP using Analysis of Dysphonia in Speech and Voice software, and HNR and vocal intensity using Praat software.

Results

Significant main effects of conditions were observed for CPP. CPP values decreased significantly when phonation changed from vowel to nasalized vowel and to nasal. There was correlation between CPP and nasalance and between CPP and intensity. HNR was slightly higher in the nasal condition than in vowel. There was a weak correlation between HNR and nasalance. No correlation was found between HNR and intensity.

Conclusions

CPP is sensitive to changes in vocal tract configuration caused by nasalization as well as intensity, whereas HNR is not. Therefore, CPP may reflect the periodicity in source signal or the filtering effects of vocal tract. Further research is needed to clarify the application and interpretation of CPP in clinical practice.

Level of Evidence

4

Laryngoscope, 129:E299–E304, 2019

Treatment Effectiveness of Novafon Local Vibration Voice Therapy for Dysphonia Treatment

BACKGROUND

The objective of this study was to explore the effectiveness of the five-week Novafon local vibration voice therapy (NLVVT) program with and without Novafon local vibration for dysphonia treatment.

METHODS

Twenty-two voice-disordered subjects were divided into two groups. The intervention group (IG) performed the NLVVT program and the control group (CG) had the same voice exercises of this program without local vibration.

RESULTS

After NLVVT, the IG showed significantly high results in all parameters of acoustics, multiparametric indices, and self-evaluation (all P values < 0.01). The CG revealed mostly much significantly lower results (P values < 0.05) or nonsignificant results for these parameters after the treatment. The intergroup comparison under consideration before and after NLVVT showed a large and significant treatment effect in voice quality (ie, narrowband spectrograms, and Acoustic Voice Quality Index), in which the IG had better treatment results. The aerodynamic measurement showed no significant changes for both groups after NLVVT (P value > 0.05).

CONCLUSION

After the NLVVT program both groups showed significant improvements of various voice measurements, in which the IG revealed better treatment results than the CG. However, next to voice exercises an extra benefit for local vibration with the Novafon appliance was assessed in voice quality.

Preliminary study of Novafon local vibration voice therapy for dysphonia treatment

Background: The objective of this study was to explore the effectiveness of a five-week Novafon local vibration voice therapy (NLVVT) program for dysphonia treatment.Methods: Eleven dysphonic subjects participated in this specific program.Results: Treatment effects were assessed during (i.e. weekly) and after NLVVT. Large and significant treatment effects were revealed in acoustics (i.e. spectrography), and multiparametric indices (i.e. Acoustic Voice Quality Index (AVQI), and Dysphonia Severity Index (DSI)) during and after NLVVT (all p values < .01). Additionally, self-evaluation (i.e. Voice Handicap Index (VHI)) showed a significant improvement after NLVVT (p < .01). Gender independent voice range profile parameters (i.e. acoustics) only showed significant effects after treatment (p ≤ .01), but not during the treatment. Finally, aerodynamic measurement (i.e. phonation quotient) showed low treatment effects after NLVVT, which were not significant (p > .05).Conclusions: The preliminary results showed that NLVVT might be successful in voice treatment. Large treatment effects might be expected in AVQI, DSI, spectrography and VHI after using NLVVT. Other voice characteristics showed smaller treatment effects (i.e. voice range profile parameters) or no meaningful treatment effects (i.e. phonation quotient).

Short-Term Effect of Two Semi-Occluded Vocal Tract Training Programs on the Vocal Quality of Future Occupational Voice Users: "Resonant Voice Training Using Nasal Consonants" Versus "Straw Phonation"

PURPOSE

The purpose of this study was to determine the short-term effect of 2 semi-occluded vocal tract training programs, "resonant voice training using nasal consonants" versus "straw phonation," on the vocal quality of vocally healthy future occupational voice users.

METHOD

A multigroup pretest-posttest randomized control group design was used. Thirty healthy speech-language pathology students with a mean age of 19 years (range: 17-22 years) were randomly assigned into a resonant voice training group (practicing resonant exercises across 6 weeks, n = 10), a straw phonation group (practicing straw phonation across 6 weeks, n = 10), or a control group (receiving no voice training, n = 10). A voice assessment protocol consisting of both subjective (questionnaire, participant's self-report, auditory-perceptual evaluation) and objective (maximum performance task, aerodynamic assessment, voice range profile, acoustic analysis, acoustic voice quality index, dysphonia severity index) measurements and determinations was used to evaluate the participants' voice pre- and posttraining. Groups were compared over time using linear mixed models and generalized linear mixed models. Within-group effects of time were determined using post hoc pairwise comparisons.

RESULTS

No significant time × group interactions were found for any of the outcome measures, indicating no differences in evolution over time among the 3 groups. Within-group effects of time showed a significant improvement in dysphonia severity index in the resonant voice training group, and a significant improvement in the intensity range in the straw phonation group.

CONCLUSIONS

Results suggest that the semi-occluded vocal tract training programs using resonant voice training and straw phonation may have a positive impact on the vocal quality and vocal capacities of future occupational voice users. The resonant voice training caused an improved dysphonia severity index, and the straw phonation training caused an expansion of the intensity range in this population.

A systematic review of resonant voice therapy

PURPOSE

The purpose of this study is to systematically review the literature on resonant voice therapy and to evaluate the level of evidence on the effectiveness of using resonant voice therapy in treating dysphonia.

METHOD

Refereed journal papers from 1974 to 2014 were retrieved and reviewed by two independent reviewers using the keywords "Humming, Resonance, Resonant Voice, Semi-occluded or closed tube phonation" using available database systems. Quality of evidence was evaluated by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULT

Thirteen papers met the search criteria. Nine papers were selected by the two reviewers. Two of the papers were randomised-controlled studies and the other seven were observational studies. At least four types of resonant voice therapies were described. They included the Lessac-Madsen Resonant Voice Therapy, Y-Buzz, Resonance Therapy and Humming. The overall level of quality of evidence was graded as "moderate".

CONCLUSION

There were limited studies that investigated the effectiveness of resonant voice therapy. Most studies were small-scale uncontrolled observational studies with the inclusion of only small samples or specific populations. There is clearly a need for more large-scale randomised controlled studies with a wider range of populations to provide further evidence on the effectiveness of resonant voice training for different populations.

Does Cervical Muscular Contraction Affect the Measurement for Electroglottographic Perturbation Parameters?

OBJECTIVES

The purpose was to assess whether cervical muscular contraction during phonation influences the period and amplitude perturbation quotients (PPQ and APQ, respectively) of electroglottographic (EGG) signals, and whether high-pass filtering can attenuate these effects.

STUDY DESIGN

Prospective.

METHODS

We included 19 nondysphonic speakers and 21 patients with muscle tension dysphonia. During the recording of acoustic and EGG signals, each participant was instructed to naturally phonate sustained vowels /i:/ and /a:/ (NP tasks), and additionally, each nondysphonic participant was asked to phonate the same vowels in a nondysphonic voice quality while contracting the cervical muscles (muscular contracted phonation [MCP] tasks). To confirm the contraction, surface and needle electromyography (EMG) was performed. The EGG signals were high-pass filtered at different cutoff frequencies from 0 to 90 Hz and were subsequently analyzed for the PPQ and APQ.

RESULTS

Compared with the NP tasks, the MCP tasks enhanced the cervical EMG activities ranging from 0 to more than 1000 Hz, but conferred only low-frequency noise to the EGG signals under 50 Hz and increased the values for EGG-APQ, but not EGG-PPQ. These EGG-APQ values exhibited gradual decreases after high-pass filtering with an increase in the cutoff frequency ranging from 0 to 50 Hz in both groups, followed by plateaus during the MCP tasks in the nondysphonic group.

CONCLUSIONS

The present results demonstrate that cervical muscular contraction seriously affects the EGG-APQ values for unfiltered EGG signals independent of the EMG activities and that appropriate high-pass filtering over 50 Hz can attenuate these effects.