Potential Risks for Healthcare Disparities Among Individuals With Voice and Upper Airway Disorders: A Systematic Review

PURPOSE

To assess the potential epidemiological association between various possible risk factors and healthcare disparities specifically related to the access, use and/or quality of speech language pathology services for individuals with voice and upper airway disorders.

METHOD

A systematic review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis. Full text journal articles were identified through PubMed, PsycINFO and Web of Science. The reference sections of included articles were also manually screened and identified four additional studies for consideration of inclusion. Included articles specifically addressed healthcare disparities in voice and upper airway disorders related to speech pathology care. International literature was excluded. Eligible studies were reviewed and data extracted. Risk of bias of each eligible study was performed using the quality assessment tool from National Institute of Health for observational cohort and cross-sectional studies. Data from eligible studies were synthesized thematically.

RESULTS

A total of 1,101 resources were retrieved from the search; of these, 133 were duplicates. Titles and abstracts of 968 articles were screened, with 14 selected for full-text review. Eleven articles were considered eligible for inclusion. Voice disorders were the condition most frequently examined followed by only one article addressing upper airways disorders. There was considerable heterogeneity in the methodology and statistical analyses among the eligible papers. There was a lack of standard methodology for collecting and accurately determining patient characteristics as well as variability in measuring confounding variables and providing statistical analyses for such adjustments that may have impacted the findings. The information extracted from these articles revealed healthcare disparities related to sex/gender, age, insurance status/coverage, race/ethnicity, among others including etiology and preferred language.

CONCLUSIONS

This systematic review highlights the limited research on speech language pathology-specific healthcare disparities for individuals with voice and upper airway disorders. There was significant clinical and methodological heterogeneity between studies which may have contributed to varied results between studies. There is a need for greater methodological rigor and prospectively designed studies to better characterize the impact of disparities in the access to, use of, and quality of speech pathology care for this patient population.

Perceptions of employability related to severity of hypernasality: a pilot study

The primary aim of this investigation was to evaluate listener auditory-perceptual assessment of employability for individuals with hypernasal speech. Using an online survey platform, listeners with managerial experience evaluated speech samples from individuals with varying hypernasal resonance disorder severity to determine auditory-perceptual judgements regarding intelligence and employability. Speech samples of individuals with hypernasal speech were rated lower on scales of intelligence and employability, and more likely to be selected for jobs with infrequent rates of communication and lower levels of responsibility. Additionally, males with hypernasal speech were perceived as less intelligent, less employable, and more likely to be selected for a job with infrequent communication in comparison to females with hypernasal speech. Results of this preliminary investigation suggest that individuals with hypernasal speech may face employment barriers. The conclusions collected from this initial investigation open the doors for further research addressing linguistic considerations and aspects of employability. This is an important consideration for individuals with either acquired or congenitally related hypernasal resonance disorder.

A Tutorial on Skeletal Muscle Metabolism and the Role of Blood Lactate: Implications for Speech Production

PURPOSE

The purpose of this tutorial is threefold: (a) present relevant exercise science literature on skeletal muscle metabolism and synthesize the limited available research on metabolism of the adult human speech musculature in an effort to elucidate the role of metabolism in speech production; (b) introduce a well-studied metabolic serum biomarker in exercise science, lactate, and the potential usefulness of investigating this metabolite, through a well-established exercise science methodology, to better understand metabolism of the musculature involved in voice production; and (c) discuss exercise physiology considerations for future voice science research that seeks to investigate blood lactate and metabolism in voice physiology in an ecologically valid manner.

METHOD

This tutorial begins with relevant exercise science literature on the basic cellular processes of muscle contraction that require energy and the metabolic mechanisms that regenerate the energy required for task execution. The tutorial next synthesizes the available research investigating metabolism of the adult human speech musculature. This is followed by the authors proposing a hypothesis of speech metabolism based on the voice science literature and the application of well-studied exercise science principles of muscle physiology. The tutorial concludes with a discussion and the potential usefulness of lactate in investigations to better understand the metabolism of the musculature involved in vocal demand tasks.

CONCLUSION

The role of metabolism during speech (respiratory, laryngeal, and articulatory) is an understudied yet critical aspect of speech physiology that warrants further study to better understand the metabolic systems that are used to meet vocal demands.

High-Speed Videoendoscopic and Acoustic Characteristics of Inspiratory Phonation

PURPOSE

Given the importance of inspiratory phonation for assessment of vocal fold structure, the aim of this investigation was to evaluate and describe the vocal fold vibratory characteristics of inspiratory phonation using high-speed videoendoscopy in healthy volunteers. The study also examined the empirical relationship between cepstral peak prominence (CPP) and glottal area waveform measurements derived from simultaneous high-speed videoendoscopy and audio recordings.

METHOD

Vocally healthy adults (33 women, 28 men) volunteered for this investigation and completed high-speed videoendoscopic assessment of vocal fold function for two trials of an expiratory/inspiratory phonation task at normal pitch and normal loudness. Twelve glottal area waveform measures and acoustic CPP values were extracted for analyses.

RESULTS

Inspiratory phonation resulted in shorter closing time, longer duration of the opening phase, and faster closing phase velocity compared to expiratory phonation. Sex differences were elucidated. CPP changes for inspiratory phonation were predicted by changes in the glottal area index and waveform symmetry index, whereas changes in CPP during expiratory phonation were predicted by changes in asymmetry quotient, glottal area index, and amplitude periodicity.

CONCLUSIONS

Vocal fold vibratory differences were identified for inspiratory phonation when compared to expiratory phonation, the latter of which has been studied more extensively. This investigation provides important basic inspiratory phonation data to better understand laryngeal physiology in vivo and provides a basic model from which to further study inspiratory phonation in a larger population representing a broader age range.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22223812.

Updated Acoustic Normative Data through the Lifespan: A Scoping Review

OBJECTIVE

To assess the recent literature for voice acoustic data values reported for individuals without voice disorder through the lifespan as a means to develop an updated normative acoustic data resource for children and adults.

METHODS

A scoping review was conducted using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist. English language, full-text publications were identified through Medline (EBSCO & OVID), PubMed, APA PsycINFO, Web of Science, Google Scholar, and ProQuest Theses and Dissertations Global.

RESULTS

A total of 903 sources were retrieved; of these 510 were duplicates. Abstracts of 393 were screened, with 68 full-text review. From the eligible studies, citation review yielded 51 additional resources. Twenty-eight sources were included for data extraction. For the normative acoustic data extracted for males and females across the lifespan, lower fundamental frequency for adult females was observed and few studies collected semitone range, sound level range, or frequency range. Data extraction also indicated a predominately gender binary reporting of acoustic measures with few studies reporting gender identity, race, or ethnicity as variables of interest.

CONCLUSIONS

The scoping review yielded updated acoustic normative data that is of value for clinicians and researchers who rely on this normative data to make determinations about vocal function. The limited availability of acoustic data by gender, race, and ethnicity creates barriers for generalization of these normative values across all patients, clients, and research volunteers.

Inducible Laryngeal Obstruction Differential Diagnosis in Adolescents and Adults: A Tutorial

Inducible laryngeal obstruction (ILO), formerly referred to as paradoxical vocal fold motion and vocal cord dysfunction, is a complex disorder of the upper airway that requires skillful differential diagnosis. There are several medical conditions that may mimic ILO (or which ILO may mimic) that should be considered in the differential diagnosis before evidence-supported behavioral intervention is initiated to mitigate or eliminate this upper airway condition. A key in treatment planning is determination of an isolated presentation of ILO or ILO concurrent with other conditions that affect the upper airway. Accurate, timely differential diagnosis in the clinical assessment of this condition mitigates delay of targeted symptom relief and/or insufficient intervention. Accurate assessment and nuanced clinical counseling are necessary to untangle concurrent, competing conditions in a single patient. This tutorial describes the common and rare mimics that may be encountered by medical professionals who evaluate and treat ILO, with particular attention to the role of the speech-language pathologist. Speech-language pathologists receive referrals for ILO from several different medical specialists (allergy, pulmonology, and sports medicine), sometimes without a comprehensive team assessment. It is paramount that speech-language pathologists who assess and treat this disorder have a solid understanding of the conditions that may mimic ILO. Summary tables that delineate differential diagnosis considerations for airway noise, origin of noise, symptoms, triggers, role of the speech-language pathologist, and β-agonist response are included for clinician reference. A clinical checklist is also provided to aid clinicians in the critical assessment process.

Framing Disparities in Access to Medical Speech-Language Pathology Care in Rural Alabama

PURPOSE

Rural-living residents of Alabama depend on rural hospitals and clinics staffed with physicians and allied health professionals including speech-language pathologists (SLPs). The purpose of the exploratory study was to examine the speech-language pathology workforce in health care facilities in nonmetropolitan Alabama counties to determine potential disparities in access and identify medical SLP deserts for rural Alabamians.

METHOD

The hospitals, rural health clinics, nursing homes, and rehabilitation centers for each of the 37 nonmetropolitan counties were identified through the 2020 Alabama Department of Public Health directories, and phone surveys were completed to determine medical SLP staffing at each facility. Descriptive statistics and regression analysis were conducted.

RESULTS

The initial review yielded 229 rural health care facilities with 223 ultimately included in the analysis and 176 facilities completing a phone inquiry (76.68%). Sixty-one (35.88%) reported employing at least one SLP and no facility stated staffing SLP assistants. Linear regression indicated a positive, yet moderate effect size between the reported number of SLPs staffed within each county and specific population of the county (r ² = .519). Anecdotally, facilities reported difficulty in hiring and retaining SLPs due to rural geographical location.

CONCLUSIONS

The exploratory findings suggest disparities in access to behavioral communication and swallowing care for rural residents in the state. The methodology employed for data collection and analysis may be applied to other states and U.S. territories, in an effort to frame the issue nationally and support rural health care policy across the United States. Further investigation regarding the cost effectiveness of telepractice, the availability of broadband Internet access, the efficacy of community-based service delivery, and the effectiveness of incentivized rural SLP graduate programs is warranted to mitigate the disparities in access.

Sex and Race Reporting and Representation in Noncancerous Voice Clinical Trials: A Meta-Analysis of National Institutes of Health-Registered Research Between 1988 and 2021

PURPOSE

The purpose of this meta-analysis was to assess the frequency of sex, race, and ethnicity reporting and proportional representation in funded, noncancerous voice clinical trials to determine the state of compliance with National Institutes of Health (NIH) guidelines for inclusivity in clinical research.

METHOD

Clinical trials registered with the NIH/U.S. National Library of Medicine between January 1988 and September 2021 were analyzed. Primary reports of the trials were obtained from clinicaltrials.gov and PubMed. Outcomes included the proportion of trials reporting sex, race, and ethnicity and the proportion of participants by sex, race, and ethnicity in the trials. Descriptive statistics and chi-square tests were used to analyze the data with 95% confidence intervals (CIs) reported.

RESULTS

The search yielded 46 research studies. After inclusion and exclusion criteria were applied and attempts to locate studies were conducted, 11 total articles were ultimately evaluated. Descriptively, there were more female subjects, yet overall, no significant difference in sex distribution (χ² = 0.07, p = .75, 95% CI [-0.25, -0.19]). Race and ethnicity were only reported in two clinical trials. Black participants were underrepresented in one clinical trial (χ² = 4.93, p = .02, 95% CI [-0.11, -0.02]), whereas Hispanic participants were underrepresented in a second trial (χ² = 11.27, p < .00, 95% CI [-0.20, - 0.13]).

CONCLUSIONS

This preliminary analysis highlights the disparities in race and ethnicity recruitment and reporting in noncancerous voice clinical trials. There is a need for strategic recruitment strategies and improved reporting practices to adhere to the NIH inclusivity directives.

Bacillus velezensis AP183 Inhibits Staphylococcus aureus Biofilm Formation and Proliferation in Murine and Bovine Disease Models

The increasing frequency of S. aureus antimicrobial resistance has spurred interest in identifying alternative therapeutants. We investigated the S. aureus-inhibitory capacity of B. velezensis strains in mouse and bovine models. Among multiple B. velezensis strains that inhibited S. aureus growth in vitro, B. velezensis AP183 provided the most potent inhibition of S. aureus proliferation and bioluminescence in a mouse cutaneous wound (P = 0.02). Histology revealed abundant Gram-positive cocci in control wounds that were reduced in B. velezensis AP183-treated tissues. Experiments were then conducted to evaluate the ability of B. velezensis AP183 to prevent S. aureus biofilm formation on a tracheostomy tube substrate. B. velezensis AP183 could form a biofilm on a tracheostomy tube inner cannula substrate, and that this biofilm was antagonistic to S. aureus colonization. B. velezensis AP183 was also observed to inhibit the growth of S. aureus isolates originated from bovine mastitis cases. To evaluate the inflammatory response of mammary tissue to intramammary inoculation with B. velezensis AP183, we used high dose and low dose inocula in dairy cows. At the high dose, a significant increase in somatic cell count (SCC) and clinical mastitis was observed at all post-inoculation time points (P < 0.01), which resolved quickly compared to S. aureus-induced mastitis; in contrast, the lower dose of B. velezensis AP183 resulted in a slight increase of SCC and no clinical mastitis. In a subsequent experiment, all mammary quarters in four cows were induced to have grade 1 clinical mastitis by intramammary inoculation of a S. aureus mastitis isolate; following mastitis induction, eight quarters were treated with B. velezensis AP183 and milk samples were collected from pretreatment and post-treatment samples for 9 days. In groups treated with B. velezensis AP183, SCC and abundance of S. aureus decreased with significant reductions in S. aureus after 3 days post-inoculation with AP183 (P = 0.04). A milk microbiome analysis revealed significant reductions in S. aureus relative abundance in the AP183-treated group by 8 days post-inoculation (P = 0.02). These data indicate that B. velezensis AP183 can inhibit S. aureus biofilm formation and its proliferation in murine and bovine disease models.

Exercise Science and the Vocalist

The application of exercise science training knowledge has been of growing interest to voice professionals. This tutorial, derived from the authors' invited presentations from the "Exercise and the Voice" Special Session at the 2018 Voice Foundation Symposium, proposes a foundational theoretical structure based in exercise science, clarifies the wide range of variables that may influence voice training, and summarizes our present understanding of voice physiology from the perspective of muscle training. The body of literature on voice exercise was then analyzed from the perspective of this framework, identifying what we currently know and what we still have yet to learn.

High-Speed Characterization of Vocal Fold Vibrations in Normally Cycling and Postmenopausal Women: Randomized Double-Blind Analyses

Purpose The aim of this study was to examine the influence of menstrual cycle phases (follicular, ovulatory, luteal, and ischemic) and hormone levels (estradiol, testosterone, progesterone, and neuropeptide Y) on vocal fold vibrations in reproductive and postmenopausal women. Method Glottal area waveforms were extracted from high-speed videoendoscopy during sustained phonation, inhalation phonation, and voice onset/offset in the reproductive (n = 15) and postmenopausal (n = 13) groups. Linear mixed-model analysis was conducted to evaluate hormone levels and high-speed videoendoscopy outcome variables between the reproductive and postmenopausal groups. In the reproductive group, simple linear regression and multiple regression were conducted to determine the effects of hormones on the dependent variables. Results Group differences between reproductive and postmenopausal women were identified for stiffness index, oscillatory onset time, and oscillatory offset time. Neuropeptide Y hormone in the ischemic phase significantly predicted changes in the reproductive group for some dependent variables; however, the relationship varied for sustained phonation and inhalation phonation. Conclusion These findings provide preliminary evidence that vocal fold vibrations in the reproductive group are different predominantly in the ischemic phase due to neuropeptide Y changes.

Social Media as a Platform for Cyberbullying of Individuals With Craniofacial Anomalies: A Preliminary Survey

Purpose The primary aim of this study was to investigate the extent to which individuals with facial and/or speech differences secondary to a craniofacial anomaly experienced bullying through social media platforms during late school age and adolescence. Method Using an online survey platform, a questionnaire was distributed via several public and private social media groups designated for individuals with craniofacial anomaly and their caregivers. Results The majority of participants (n = 38; 88.4%) indicated they had been bullied during late school-age and adolescence and that they believed this was due to their facial difference and/or speech disorder (n = 27; 71.1%). Almost one third indicated they had been victims of cyberbullying during this time (n = 12; 31.6%) with the most common venues being texting and Facebook. Despite the large percentage of participants who reported being bullied through social media, half (n = 6) indicated they did not often report these instances of cyberbullying. Conclusions As social media use continues to increase, it appears inevitable that cyberbullying will occur. Particularly vulnerable to both traditional and cyberbullying are individuals with craniofacial anomalies. Because of the specialized training of speech-language pathologists, school-based speech-language pathologists are in a unique position to play a key role in school-wide antibullying efforts and to educate school personnel on ways in which to support the needs of children with craniofacial anomalies both inside and outside of the classroom.

Irritant-Induced Chronic Cough Triggers: A Scoping Review and Clinical Checklist

Purpose The primary aim of this review was to identify environmental irritants known to trigger chronic cough through the life span and develop a comprehensive clinically useful irritant checklist. Method A scoping review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis Extension for Scoping Reviews, checklist, and explanation. English-language, full-text resources were identified through Medline, PsycINFO, SPORTDiscus, Web of Science, and ProQuest Dissertations and Theses Global. Results A total of 1,072 sources were retrieved; of these, 109 were duplicates. Titles of abstracts of 963 articles were screened, with 295 selected for full-text review. Using the exclusion and inclusion criteria listed, 236 articles were considered eligible and 214 different triggers were identified. Triggers were identified from North America, Europe, Africa, Asia, and Australia. Occupational exposures were also delineated. Conclusions A clinically useful checklist of both frequently encountered triggers and idiosyncratic or rare triggers was developed. The clinical checklist provides a unique contribution to streamline and standardize clinical assessment of irritant-induced chronic cough. The international scope of this review extends the usefulness of the clinical checklist to clinicians on most continents.

Quantifying Vocal Power: Correlation of Whole-Body Anaerobic Power to Vocal Function Measures

Purpose The purpose of this preliminary study was to identify a vocal task that could be used as a clinical indicator of the vocal aptitude or vocal fitness required for vocally demanding occupations in a manner similar to that of the anaerobic power tests commonly used in exercise science. Performance outcomes for vocal tasks that require rapid acceleration and high force production may be useful as an indirect indicator of muscle fiber complement and bioenergetic fitness of the larynx, an organ that is difficult to study directly. Method Sixteen women (age range: 19-24 years, M _age = 22 years) were consented for participation and completed the following performance measures: forced vital capacity, three adapted vocal function tasks, and the horizontal sprint test. Results Using a within-participant correlational analyses, results indicated a positive relationship between the rate of the last second of a laryngeal diadochokinesis task that was produced at a high fundamental frequency/high sound level and anaerobic power. Forced vital capacity was not correlated with any of the vocal function tasks. Conclusions These preliminary results indicate that aspects of the laryngeal diadochokinesis task produced at a high fundamental frequency and high sound level may be useful as an ecologically valid measure of vocal power ability. Quantification of vocal power ability may be useful as a vocal fitness assessment or as an outcome measure for voice rehabilitation and habilitation for patients with vocally demanding jobs.

Data Collection Methods for the Voice Range Profile: A Systematic Review

Purpose To assess data collection variability in the voice range profile (VRP) across clinicians and researchers, a systematic review was conducted to evaluate the extent of variability of specific data collection points that affect the determination of frequency range and sound level and determine next steps in standardization of a VRP protocol. Method A systematic review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis checklist. Full-text journal articles were identified through PubMed, Web of Science, Psych Info, ProQuest Dissertations and Theses Global, Google Scholar, and hand searching of journals. Results A total of 1,134 articles were retrieved from the search; of these, 463 were duplicates. Titles and abstracts of 671 articles were screened, with 202 selected for full-text review. Fifty-four articles were considered eligible for inclusion. The information extracted from these articles revealed the methodology used to derive the VRP was extremely variable across the data points selected. Additionally, there were eight common acoustic measures used for statistical analysis described in included studies that were added as a data point. Conclusions The data collection methods for the VRP varied considerably. Standardization of procedures was recommended for clinicians and researchers.

Blood Plasma Hormone-Level Influence on Vocal Function

Purpose This preliminary study examined the influence of menstrual cycle phase and hormone levels on acoustic measurements of vocal function in reproductive and postmenopausal females. Mean fundamental frequency (f0), speaking fundamental frequency (Sf0), and cepstral peak prominence (CPP) were evaluated. It was hypothesized that Sf0 and CPP would be lower during the luteal and ischemic phases of the menstrual cycle. Group differences with lower values in postmenopausal females and greater variability in the reproductive females were also hypothesized. Method A mixed factorial analysis of variance was used to examine differences between reproductive and postmenopausal females and the four phases of the menstrual cycle. Separate analyses of variances were implemented for each of the dependent measures. Twenty-eight female participants (15 reproductive cycling, 13 postmenopausal) completed the study. Participants were recorded reading the Rainbow Passage and sustaining the vowel /a/. Mean vocal f0, Sf0, and CPP were determined from the acoustic samples. Blood assays were used to determine estrogen, progesterone, testosterone, and neuropeptide Y levels at four data collection time points. Results Group differences in hormone levels and Sf0 values were established with the postmenopausal group having significantly lower hormone levels and significantly lower Sf0 than the reproductive cycling group across the phases. Analysis of the reproductive group by hormone levels and cycle phase revealed no significant differences for CPP or Sf0 across phases. Higher estrogen was identified in the ovulation phase, and higher progesterone was identified in the luteal phase. Conclusions Significant differences in hormone levels and Sf0 were identified between groups. Within the reproductive cycling group, the lack of significant difference in acoustic measures relative to hormone levels indicated that the measures taken may not have been sensitive enough to identify hormonally mediated vocal function changes. The participant selection may have biased the findings in that health conditions and medications that are known to influence voice function were used as exclusion criteria.

Implications of Compression Race Suit on Forced Vital Capacity: Assessment Considerations for Paradoxical Vocal Fold Motion in Competitive Female Swimmers

Purpose The purpose of this investigation was to quantify the extent to which forced vital capacity (FVC) in competitive swimmers may differ from nonswimmers and determine if compression race suits reduced FVC when compared to practice swimsuits. Identification of the differences in FVC between swimmers and nonswimmers as well as pulmonary function differences secondary to swimsuit construction may inform assessment of the competitive swimmer with paradoxical vocal fold motion (PVFM). Method Using a prospective, mixed within- and between-groups, repeated measures design with 10 female competitive swimmers and 13 female nonswimmers, FVC was measured and compared between the two groups. Further FVC assessment was completed with the swimmers to identify FVC differences between a practice suit and a compression racing suit. Results FVC in swimmers was significantly larger than FVC in nonswimmers by over 1 L. The predicted FVC volumes were significantly smaller than the actual FVC volumes for swimmers. No significant differences were identified between the practice swimsuit and the compression race suit or between the predicted and actual FVCs for the nonswimmer group. Conclusions Swimmers have unique pulmonary function and physiology that require consideration during the assessment for PVFM to ascertain the extent to which the pulmonary system may be compromised from PVFM, reduced exercise intensity, or both. Knowledge of differential diagnoses and adequate characterization of pulmonary volumes in swimmers will improve assessment processes.

Toward a Consensus Description of Vocal Effort, Vocal Load, Vocal Loading, and Vocal Fatigue

Purpose The purpose of this document is threefold: (a) review the uses of the terms "vocal fatigue," "vocal effort," "vocal load," and "vocal loading" (as found in the literature) in order to track the occurrence and the related evolution of research; (b) present a "linguistically modeled" definition of the same from the review of literature on the terms; and (c) propose conceptualized definitions of the concepts. Method A comprehensive literature search was conducted using PubMed/MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scientific Electronic Library Online. Four terms ("vocal fatigue," "vocal effort," "vocal load," and "vocal loading"), as well as possible variants, were included in the search, and their usages were compiled into conceptual definitions. Finally, a focus group of eight experts in the field (current authors) worked together to make conceptual connections and proposed consensus definitions. Results The occurrence and frequency of "vocal load," "vocal loading," "vocal effort," and "vocal fatigue" in the literature are presented, and summary definitions are developed. The results indicate that these terms appear to be often interchanged with blurred distinctions. Therefore, the focus group proposes the use of two new terms, "vocal demand" and "vocal demand response," in place of the terms "vocal load" and "vocal loading." We also propose standardized definitions for all four concepts. Conclusion Through a comprehensive literature search, the terms "vocal fatigue," "vocal effort," "vocal load," and "vocal loading" were explored, new terms were proposed, and standardized definitions were presented. Future work should refine these proposed definitions as research continues to address vocal health concerns.

Upper Airway Thermoregulation During Singing Warm-Up

The primary aim of this research was to quantify the degree to which the upper airway temperature changes with singing warm-up. Based on prior upper airway thermoregulation research it was hypothesized that upper airway temperature would not significantly increase during singing warm up when compared to prewarm up and recovery phases. Ten participants completed a short singing warm-up of their choice until they felt sufficiently warmed up while upper airway temperature was measured at 1 second intervals via a transnasal thermistor placed against the posterior pharyngeal wall, just above the larynx. Descriptive statistics and statistical modeling were used for comparison of pre-warm-up, warm-up, and recovery phases of a short singing warm-up. Results indicated a physiologically-significant increase (≥0.5°C) of upper airway temperature during the singing warm-up when compared to the prewarm up average. Significant differences (P < 0.0001) were identified between all pairwise comparisons analyzed for the three phases of data collected (baseline, warm-up, and recovery). These findings support an upper airway tissue temperature increase in response to the singing warm-up. The extent to which these findings can be generalized to the intrinsic laryngeal muscles is still unknown given the technical difficulty of obtaining intramuscular laryngeal temperature measures.

Neuromuscular Development in Neonates and Postnatal Infants: Implications for Neuromuscular Electrical Stimulation Therapy for Dysphagia

Purpose The aim of the current study was to review neuromuscular development, summarize the current body of evidence describing the use of neuromuscular electrical stimulation (NMES) therapy in infants, and identify possible contraindications for the use of NMES in the neonate and young infant. Method After a review of the literature describing neuromuscular development, we created a timeline of the developmental processes. Key milestones were determined, and a literature search was conducted to identify potential effects of electrical stimulation on this process. Results Current evidence supporting the use of NMES in the pediatric population is limited and of poor quality. Contraindications of the use of NMES in the neonate and young infant were identified, including (a) inhibited expression of the neural cell adhesion molecule that is vital for neuromuscular development, (b) alteration of muscle fiber type metabolic profile away from intended muscle fiber type morphology, and (c) interruption of postsynaptic acetylcholine receptor synthesis during neuromuscular junction development. Conclusion The use of NMES for the treatment of dysphagia in the neonate and young infant may influence early neuromuscular development in a manner that is not currently well understood. Future research is needed to further understand the effects of NMES on the developing neuromuscular system.

A Tutorial of the Effects of Sex Hormones on Laryngeal Senescence and Neuromuscular Response to Exercise

Purpose The purpose of this tutorial is to summarize how sex hormones affect both laryngeal senescence and neuromuscular response to exercise, highlighting the importance of considering sex differences in developing treatment for the senescent voice. Conclusion Men and women's voices are sexually dimorphic throughout the life span, including during the laryngeal adaptations observed during senescence. Therefore, presbyphonia (age-related dysphonia) likely clinically manifests differently for men and women due to differences in how the male and the female larynx change in response to aging. Because sexual dimorphism is evident in both laryngeal aging and response to exercise, voice therapy programs aimed at treating the typical and disordered aged voice should consider sex differences in their design.

Neuropeptide Y and dipeptidyl peptidase IV in normally cycling and postmenopausal women: A prospective pilot study

The purpose was to investigate changes in neuropeptide Y (NPY) protein and dipeptidyl peptidase IV (DPP-IV) activity in the plasma and saliva in normally cycling women and women after menopause. We recruited 7 cycling women and 7 postmenopausal women for a cross-sectional, prospective pilot study. Blood via venipuncture and saliva samples were taken at each point in the menstrual cycle (premenopausal) or once per week (postmenopausal) for 2 months. Blood and saliva were analyzed for estrogen, NPY using ELISA and DPP-IV activity using a fluorometric assay. Plasma β-estradiol was an average of 96.45 ± 57.04 pg/mL over 2 cycles in the premenopausal group and 1.72 ± 0.35 pg/mL over 2 months in the postmenopausal group (P < .05). In the cycling group, there were no significant differences in saliva or plasma NPY or DPP-IV over the cycle. For the postmenopausal group, salivary NPY and DPP-IV did not change over 2 months. Plasma NPY was lowest in the middle 2 weeks (average: 0.52 ± 0.10 ng/mL) compared to the first and fourth weeks (average of week 1 and 4: 0.60 ± 0.14 ng/mL; P < .05). Plasma NPY in postmenopausal women was higher overall (0.56 ± 0.13 ng/mL) compared to cycling women (0.30 ± 0.11 ng/mL; P < .05). Plasma DPP-IV activity was unchanged by time in the postmenopausal group. Saliva DPP-IV and saliva NPY in the cycling group had a significant negative correlation (R = -0.95; P < .05). We found that saliva measures of NPY and DPP-IV activity appear to be poor estimates of plasma concentrations and activities, but a larger sample size is required to conform this. Differences in plasma NPY concentrations between the groups and the relationship between salivary NPY and DPP-IV suggests that there may be some unique differences between these groups.

Acquired Velopharyngeal Dysfunction: Survey, Literature Review, and Clinical Recommendations

PURPOSE

The aim of this study was to describe the clinical assessment recommendations for acquired velopharyngeal dysfunction (AVPD) and, through a literature review and online survey, summarize current practice patterns for evaluation and treatment pathway determination for this target population.

METHOD

An online survey to query current assessment procedures and treatment pathway recommendations for AVPD was developed. Following survey results, a literature review was completed to determine evidence-based recommendations for assessment procedures and intervention recommendations based on assessment findings. Literature search terms included the following: acquired velopharyngeal dysfunction, hypernasality, non-cleft velopharyngeal dysfunction, velopharyngeal dysfunction, velopharyngeal dysfunction AND iatrogenic, velopharyngeal dysfunction AND neurogenic, velopharyngeal dysfunction AND assessment OR evaluation, velopharyngeal dysfunction AND treatment OR intervention, velopharyngeal dysfunction AND practice patterns OR clinical guidelines, velopharyngeal insufficiency. Inclusion criteria were limited to practice patterns/recommendations for assessment and/or treatment recommendations for AVPD, English language articles published between 2000 and 2017, and peer-reviewed journals. Studies regarding solely congenital or cleft palate velopharyngeal dysfunction and intervention outcome studies were excluded. Forty articles met inclusionary criteria.

RESULTS

The online survey results indicated lack of consensus for AVPD assessment and treatment recommendation protocols, with 93% of respondents indicating the need for a clinical guide for developing treatment recommendations. The majority of recommendations were filtered into an algorithm for clinical decision making.

CONCLUSIONS

Clinical uncertainty among speech-language pathologists surveyed and the paucity of published clinical guidelines for assessing individuals with AVPD indicate the need for additional clinical research for this disorder, one that is heterogeneous and distinct from those with congenital velopharyngeal dysfunction. The proposed evidence-based clinical worksheet may assist in determining management for patients with AVPD and may serve as a starting place for validation of a clinical guideline.

Elementary School Teachers' Vocal Dose: Muscle Bioenergetics and Training Implications

PURPOSE

Translating exercise-science methodology for determination of muscle bioenergetics, we hypothesized that the temporal voice-use patterns for classroom and music teachers would indicate a reliance on the immediate energy system for laryngeal skeletal-muscle metabolism. It was hypothesized that the music-teacher group would produce longer voiced segments than the classroom teachers.

METHOD

Using a between- and within-group multivariate analysis-of-variance design (5 classroom teachers; 7 music teachers), we analyzed fundamental-frequency data-collected via an ambulatory phonation monitor-for length (seconds) of voiced and nonvoiced intervals. Data were collected for 7.5 hr during the workday, over the course of several workdays for each teacher.

RESULTS

Descriptive analyses of voiced and nonvoiced intervals indicated that over 99% of voiced segments for both groups were no longer than 3.15 s, supporting the hypothesis of reliance on the immediate energy system for muscle bioenergetics. Significant differences were identified between and within the classroom- and music-teacher groups, with the music-teacher group producing longer voiced segments overall.

CONCLUSIONS

Knowledge of probable intrinsic laryngeal skeletal-muscle bioenergetics requirements could inform new interdisciplinary considerations for voice habilitation and rehabilitation.

Muscle Bioenergetic Considerations for Intrinsic Laryngeal Skeletal Muscle Physiology

PURPOSE

Intrinsic laryngeal skeletal muscle bioenergetics, the means by which muscles produce fuel for muscle metabolism, is an understudied aspect of laryngeal physiology with direct implications for voice habilitation and rehabilitation. The purpose of this review is to describe bioenergetic pathways identified in limb skeletal muscle and introduce bioenergetic physiology as a necessary parameter for theoretical models of laryngeal skeletal muscle function.

METHOD

A comprehensive review of the human intrinsic laryngeal skeletal muscle physiology literature was conducted. Findings regarding intrinsic laryngeal muscle fiber complement and muscle metabolism in human models are summarized and exercise physiology methodology is applied to identify probable bioenergetic pathways used for voice function.

RESULTS

Intrinsic laryngeal skeletal muscle fibers described in human models support the fast, high-intensity physiological requirements of these muscles for biological functions of airway protection. Inclusion of muscle bioenergetic constructs in theoretical modeling of voice training, detraining, fatigue, and voice loading have been limited.

CONCLUSIONS

Muscle bioenergetics, a key component for muscle training, detraining, and fatigue models in exercise science, is a little-considered aspect of intrinsic laryngeal skeletal muscle physiology. Partnered with knowledge of occupation-specific voice requirements, application of bioenergetics may inform novel considerations for voice habilitation and rehabilitation.

Vocal Ergonomics in the Workplace: Heating, Ventilation, and Air-Conditioning Method Influences on Vocal Comfort and Function

PURPOSE

The purpose of this study was to examine the influence of the heating, ventilation, and air-conditioning method on voice function following a voicing task using ecologically valid offices, one with radiant HVAC and one with forced air.

METHOD

A total of 12 consented participants (6 women, 6 men) narrated a video in each of 4 environmental conditions in a within-between repeated-measures design. Acoustic data were collected with an ambulatory phonation monitor and perceived phonatory effort was determined following the voicing task. Data were analyzed using a within-between repeated-measures analysis of variance with significance set at α < .05.

RESULTS

Perceived phonatory effort did not differ between environments; however, a significant difference in vocal amplitude between 2 trials was identified for the male participants and physiologically significant differences in vocal amplitude were identified for male and female participants.

CONCLUSIONS

The findings suggest that perceived phonatory effort may not be a sensitive measure of vocal function differences following a voicing task in ecologically valid office spaces despite significant acoustic findings. Future research should address longer exposure to environmental differences combined with a longer voicing task within ecologically valid work spaces as well as the recruitment of participants who have particular vulnerability to environmental perturbations.

Vocal function and upper airway thermoregulation in five different environmental conditions

PURPOSE

Phonation threshold pressure and perceived phonatory effort were hypothesized to increase and upper airway temperature to decrease following exposure to cold and/or dry air. Greater changes were expected with mouth versus nose breathing.

METHOD

In a within-participant repeated measures design, 15 consented participants (7 men, 8 women) completed 20-min duration trials to allow for adequate thermal equilibration for both nose and mouth breathing in 5 different environments: 3 temperatures (°C) matched for relative humidity (% RH), cold (15 °C, 40% RH), thermally neutral (25 °C, 40% RH), and hot (35 °C, 40% RH); and 2 temperatures with variable relative humidity to match vapor pressure for the neutral environment (25 °C, 40% RH), cold (15 °C, 74% RH) and hot (35 °C, 23% RH). Following each equilibration trial, measures were taken in this order: upper airway temperature (transnasal thermistor probe), phonation threshold pressure, and perceived phonatory effort.

RESULTS

Data were analyzed using repeated measures analysis of variance, and no significant differences were established.

CONCLUSIONS

The study hypotheses were not supported. Findings suggest that the upper airway is tightly regulated for temperature when challenged by a realistic range of temperature and relative humidity environments. This is the first study of its kind to include measurement of upper airway temperature in conjunction with measures of vocal function.

Perioperative Voice Recovery: An Exercise Physiology Perspective

Voice professionals have differing views on the amount of voice rest prescribed before and after laryngeal surgery. Current recommendations are largely based on a long-standing belief that voice rest is good for the vocal mechanism, particularly when pathology is present or following surgical interruption of the vocal fold tissue. There is little evidence to support the benefit of extensive voice rest prior to laryngeal surgery, as is often recommended in the performing arts. In fact, preoperative voice therapy has shown benefit for postoperative voice outcome. From a wound-healing perspective, voice conservation immediately following vocal fold surgery contributes to the best vocal function outcome. There is no supportive evidence for postoperative voice rest that extends for weeks into months, as some performing artists have reported following surgery. From the perspective of skeletal muscle cell physiology and what is currently known about skeletal muscle adaptations that occur with training and detraining, a guideline for optimal voice recovery and return to performance may be clearer. The well-intentioned, long-held belief that extensive voice conservation is good for the voice may actually trigger a skeletal muscle detraining cascade that could lengthen return to optimal voice function, particularly in the vocal performing arts.

Assessment of phonation threshold pressure: a critical review and clinical implications

PURPOSE

To describe the origins of the task elicitation procedure for determining phonation threshold pressure and, through a literature review and online survey, describe published procedural, environmental, and participant variable departures from the original methodology.

METHOD

Literature search terms included phonation threshold pressure, subglottal pressure and phonation, pressure measurement and phonation, lung pressure and phonation, and vocal fold oscillation onset. Inclusion criteria were limited to indirect assessment of phonation threshold pressure, English language publications between 1980 and 2009, and peer-reviewed journals. Studies including animals, computer or physical models, alaryngeal speakers, laryngeal airway resistance, or any airflow interruption technique were excluded. Twenty-four articles matched the inclusionary criteria. An online survey to query task elicitation procedures was then developed from the literature review.

RESULTS

The scientific rationale for inclusion of phonation threshold pressure data was consistent across published studies; however, variations in procedural methodology for task elicitation were identified, as were environmental and participant inconsistencies that might affect phonation threshold pressure values. Findings of the online survey mirrored the inconsistencies identified in the literature review.

CONCLUSIONS

The methodological differences for task elicitation identified in this comprehensive review of the literature and the online survey, while bringing into question the reliability of phonation threshold pressure measurement, illuminate scientific questions yet to be answered to further refine and potentially standardize phonation threshold pressure as a more reliable research and clinical measurement.

A Mindful Approach to Stuttering Intervention

The purpose of this paper is to describe the construct of mindfulness and how this can be applied to stuttering intervention. To increase understanding of the construct, mindfulness is defined, its origin is discussed, and the ways it is traditionally taught and assessed are reviewed. The use of mindfulness in stuttering intervention to facilitate improved well-being, desensitization, increased self-acceptance, reduction of stress and anxiety, and increased internal locus of control also is discussed.

Influence of syllable train length and performance end effects on estimation of phonation threshold pressure

OBJECTIVES

The purpose of this study was to determine whether the number of syllables collected and performance end effects had a significant effect on phonation threshold pressure (PTP) estimates.

METHODS

Ten adult females with normal voices produced five- and seven-syllable trains of /pi/ at low, modal, and high pitches. The results were analyzed using repeated-measures analysis of variance to determine whether a difference existed in PTP when a five-syllable train was collected versus when a seven-syllable train was collected and whether the typically discarded first and last syllables within a train differed from the middle syllables.

RESULTS

The results indicated that there was no significant difference in estimated PTP values when calculated from a five-syllable versus a seven-syllable train or between the first, middle, and last syllables within a train.

CONCLUSIONS

Based on these findings, it appears that a five-syllable train provides adequate information from which to estimate PTP values. Furthermore, these findings also suggest that within the five-syllable train, any three adjacent syllables could be used to estimate PTP. These findings are significant in developing a clinically standardized, effective, and efficient method for collecting PTP.

Translating Exercise Science Into Voice Care

The basic principles of exercise training for skeletal muscle adaptations have been applied to voice training for some time. To date, the use of the basic principles of muscle training for designing a voice rehabilitation program or advising voice clients about the role of voice rest and modified voice use following surgical intervention has not been well developed. Voice training is a complex process of skill acquisition through application of motor learning principles and the concurrent coordinated use of many physiologic systems. However, the translation of exercise science literature to voice training and recovery needs to be undertaken with caution, because the function and performance of laryngeal skeletal muscle can be different from those of skeletal muscles used for other types of movement. This discussion will be confined to the basic adaptations of the muscle tissue itself. A brief review of basic principles of muscle training as understood for skeletal muscle will be followed by a more extensive discussion of the neurologic, metabolic, and physiologic adaptations of muscle training and detraining. Translation of this body of literature will be considered in the contexts of post-surgical voice recovery, voice rehabilitation, and maintenance of professional voice requirements.

Paradoxical vocal fold motion in children and adolescents

Paradoxical vocal fold motion (PVFM) is a complex adductory disorder of the vocal folds that frequently is mistaken for asthma. PVFM typically requires behavioral intervention by a trained speech-language pathologist for complete resolution of the symptoms. Once thought to be limited to adults, PVFM has been increasingly documented and successfully treated in the child and adolescent population. Understanding PVFM requires thorough knowledge of the differential diagnoses, the clinical features of PVFM, the differentiation of PVFM from asthma, the medical professionals involved in the diagnosis and treatment, and the behavioral interventions that are commonly prescribed. Teachers, school nurses, and coaches may be the first professionals to see the symptoms in children and assume that they have asthma. Successful referral, diagnosis, and behavioral treatment requires a team of individuals in the child's community, including the school speech-language pathologist, who can work together to ensure identification and resolution of the symptoms. This article discusses etiologies, differential diagnosis, referral, medical management, evaluation, and behavioral treatment of the child or adolescent with PVFM.