Perturbation and nonlinear dynamic analysis of adult male smokers

Prevalence of Laryngopharyngeal Reflux Symptoms, Dysphonia, and Vocal Tract Discomfort in Amateur Choir Singers

INTRODUCTION

Vocal tract discomfort (VTD), dysphonia, and laryngopharyngeal reflux (LPR) symptoms are complaints frequently reported by amateur singers. There are two aims of this study. The first is to evaluate the prevalence of these symptoms using validated questionnaires. The second is to correlate singing-related variables with the questionnaire responses.

METHODS

A total of 392 amateur choir singers (ACS) and 514 control subjects completed an online survey divided into four parts: (1) clinical and demographic characteristics, (2) training in singing and singing experience, (3) history of gastroesophageal reflux disease and LPR symptoms, (4) validated questionnaires. Specifically, the reflux symptom index (RSI), the vocal tract discomfort scale (VTDS), and the voice symptom scale (VoiSS) were included to analyze the actual burden related to LPR symptoms, VTD, and dysphonia.

RESULTS

ACS demonstrated a healthier lifestyle and a lower prevalence of gastroesophageal reflux disease symptoms in comparison with control subjects. ACS scored significantly higher in VTDS and VoiSS than control subjects, while no differences in the RSI results were found. Significant correlations among the questionnaires' results were demonstrated. Occasional professional singing was the variable influencing VTDS and VoiSS results the most.

CONCLUSION

ACS do not evidently manifest a higher impairment connected to LPR (RSI score), while they do report higher levels of voice (VoiSS score) and vocal tract (VTDS score) impairments, in comparison with control subjects. The relevant correlations among the PRO measures suggest that LPR symptoms, VTD, and dysphonia are related to each other. Given the relevant repercussion on the severity of VTD and dysphonia, providers should specifically ask about occasional professional singing when treating amateur singers.

Wildfire smoke linked to vocal changes in wild Bornean orangutans

Tropical peatlands are the sites of Earth's largest fire events, with outsized contributions to greenhouse gases, toxic smoke, and haze rich with particulate matter. The human health risks from wildfire smoke are well known, but its effects on wildlife inhabiting these ecosystems are poorly understood. In 2015, peatland fires on Borneo created a thick haze of smoke that blanketed the region. We studied its effects on the long call vocalizations of four adult male Bornean orangutans (Pongo pygmaeus wurmbii) in a peat swamp forest. During the period of heavy smoke, orangutans called less often and showed reduced vocal quality-lower pitch, increased harshness and perturbations, and more nonlinear phenomena-similar to changes in human smokers. Most of these changes persisted for two months after the smoke had cleared and likely signal changes in health. Our work contributes valuable information to support non-invasive acoustic monitoring of this Critically Endangered primate.

Towards the Objective Speech Assessment of Smoking Status based on Voice Features: A Review of the Literature

BACKGROUND AND OBJECTIVE

In smoking cessation clinical research and practice, objective validation of self-reported smoking status is crucial for ensuring the reliability of the primary outcome, that is, smoking abstinence. Speech signals convey important information about a speaker, such as age, gender, body size, emotional state, and health state. We investigated (1) if smoking could measurably alter voice features, (2) if smoking cessation could lead to changes in voice, and therefore (3) if the voice-based smoking status assessment has the potential to be used as an objective smoking cessation validation method.

METHODS

A systematic review of the scientific literature was conducted to compile studies on smoking status assessment based on voice features. We searched nine scientific databases for original studies involving the effects of smoking on voice features, the effects of smoking cessation on voice features.

RESULTS

A total of 34 studies were identified for review. We found that fundamental frequency, jitter, shimmer, harmonics to noise ratio, and other voice features are affected by smoking and could be used to assess smoking status.

CONCLUSION

Speech assessment of smoking status based on voice features has potential as a smoking status validation method, as it is simple, reliable, and less time-consuming. Furthermore, this study provides recommendations for future research on the objective speech assessment of smoking status based on voice features.

Things to Consider When Automatically Detecting Parkinson’s Disease Using the Phonation of Sustained Vowels: Analysis of Methodological Issues

Diagnosing Parkinson’s Disease (PD) necessitates monitoring symptom progression. Unfortunately, diagnostic confirmation often occurs years after disease onset. A more sensitive and objective approach is paramount to the expedient diagnosis and treatment of persons with PD (PwPDs). Recent studies have shown that we can train accurate models to detect signs of PD from audio recordings of confirmed PwPDs. However, disparities exist between studies and may be caused, in part, by differences in employed corpora or methodologies. Our hypothesis is that unaccounted covariates in methodology, experimental design, and data preparation resulted in overly optimistic results in studies of PD automatic detection employing sustained vowels. These issues include record-wise fold creation rather than subject-wise; an imbalance of age between the PwPD and control classes; using too small of a corpus compared to the sizes of feature vectors; performing cross-validation without including development data; and the absence of cross-corpora testing to confirm results. In this paper, we evaluate the influence of these methodological issues in the automatic detection of PD employing sustained vowels. We perform several experiments isolating each issue to measure its influence employing three different corpora. Moreover, we analyze if the perceived dysphonia of the speakers could be causing differences in results between the corpora. Results suggest that each independent methodological issue analyzed has an effect on classification accuracy. Consequently, we recommend a list of methodological steps to be considered in future experiments to avoid overoptimistic or misleading results.

Correlation Between Subjective and Objective Parameters of Voice in Elderly Male Speakers

INTRODUCTION

Literature review suggests that the analysis of acoustic, cepstral, and spectral parameters of voice offers excellent discrimination between the normal and pathological voices and strongly correlates with the perception of voice quality. Although the correlation between the subjective and objective voice measures can facilitate the clinician to distinguish pathological voices from normal voices, only a handful of investigations have examined the relationship between these measures in aging voices.

OBJECTIVES

To investigate the differences in the subjective and objective parameters (acoustic, spectral, and cepstral parameters) of the voice in elderly male speakers with and without symptoms of dysphonia, and to document the correlation between the subjective and objective parameters in the voice of elderly male speakers.

STUDY DESIGN

Retrospective standard group comparison study.

METHODS

Phonation and speech samples were collected from 30 elderly male participants having no vocal symptoms related to dysphonia and 30 elderly male participants with the self-reported presence of vocal symptoms related to dysphonia. The subjective, acoustic, spectral, and cepstral parameters were analyzed from all the voice samples.

RESULTS

Results revealed significant differences in subjective, acoustic, cepstral, and spectral parameters of voice between the voice samples of the elderly individuals with and without dysphonic symptoms. Perceptual parameters showed a weak and moderate correlation with acoustic parameters and a strong correlation with spectral and cepstral parameters of voice.

CONCLUSION

Further studies on the correlation between the subjective and objective parameters of voice in elderly male speakers with various types of laryngeal pathologies would throw light on distinguishing the voice of normal aging from the impact of any associated laryngeal pathology to make diagnostic distinctions.

Reflux symptoms in professional opera soloists

BACKGROUND

Professions distinguished by repeated vocal stress carry a high risk of developing gastroesophageal reflux symptoms (GERS) which may affect vocal performance.

AIMS

To investigate the prevalence of self-reported GERS in professional opera soloists.

METHODS

A validated questionnaire regarding self-reported GERS (heartburn, regurgitation, chest pain, dysphagia, hoarseness, and cough) and lifestyle habits was administered to 116 professional opera soloists (mean age 34.1 ± 7.3 years, F:M ratio 1:1.1). Age and sex-matched opera choristers and control subjects were used as control. Prevalence rate ratios (PRRs) adjusted for confounding factors were evaluated.

RESULTS

Among GERS, belching (33.6%), heartburn (19.8%), and dysphagia (15.5%) were the most commonly reported by soloists. In particular, a higher risk of heartburn (PRR 2.61, 95% CI 1.45-4.69) and dysphagia (PRR 2.58, 95% CI 1.31-5.10) was reported in soloists as compared to choristers. The prevalence of obesity and late dinner was higher in both choristers and soloists in comparison to the population sample (p < 0.001). GERS was more common among soloists who received pharmacologic treatment and their prevalence was unrelated to the years of singing activity.

CONCLUSIONS

Professional opera soloists, regardless of the length of their career, are predisposed to developing GERS. Physicians should encourage patients to correct preventable risk factors. A prolonged pharmacological treatment might be needed.

The Effect of Electronic Cigarettes on Voice Quality

OBJECTIVES

Cigarette-associated diseases have frequently been detected in the field of otolaryngology. Cigarettes can cause changes in voice performance. The aim of the present study was to investigate the effect of e-cigarettes on voice performance compared with conventional cigarettes.

MATERIALS AND METHODS

This is a cross-sectional study that included 81 healthy volunteers. To provide standardization, all patients were men. The patients were divided into three groups: e-cigarette users (group 1, n = 21), conventional cigarette users (group 2, n = 30), and nonsmokers who had never smoked (group 3, n = 30). The subjective and objective voice analyses were performed for all the three groups in the study. F0, jitter %, shimmer %, shimmer dB, harmonics-to-noise ratio (HNR) values, and Voice Handicap Index 10 were statistically compared between all groups.

RESULTS

The mean Voice Handicap Index 10 values of the conventional cigarette users were higher than those of the e-cigarette users and control group. No significant difference regarding the F0, jitter, and shimmer percentage values between the groups was detected; however, a significant difference was detected regarding the shimmer dB and HNR values between the groups. The mean shimmer dB values of the conventional cigarette group were higher than those of the control group and electronic cigarette users, but the mean HNR values were lower than those of the control group and electronic cigarette users.

CONCLUSIONS

The effects of e-cigarettes on voice were detected as mild compared with conventional cigarettes, according to the subjective and objective voice analysis results in our study.

Acoustic and Perceived Measurements Certifying Tango as Voice Treatment Method

Voice disorders are affecting everyday life in many levels, and their prevalence has been studied extensively in certain and general populations. Notably, several factors have a cohesive influence on voice disorders and voice characteristics. Several studies report that health and environmental and psychological etiologies can serve as risk factors for voice disorders. Many diagnostic protocols, in the literature, evaluate voice and its parameters leading to direct or indirect treatment intervention. This study was designed to examine the effect of tango on adult acoustic voice parameters. Fifty-two adults (26 male and 26 female) were recruited and divided into four subgroups (male dancers, female dancers, male nondancers, and female nondancers). The participants were asked to answer two questionnaires (Voice Handicap Index and Voice Evaluation Form), and their voices were recorded before and after the tango dance session. Moreover, water consumption was investigated. The study's results indicated that the voices' acoustic characteristics were different between tango dancers and the control group. The beneficial results are far from prominent as they prove that tango dance can serve stand-alone as voice therapy without the need for hydration. Also, more research is imperative to be conducted on a longitudinal basis to obtain a more accurate result on the required time for the proposed therapy.

Using Receiver Operating Characteristic Curve to Define the Cutoff Points of Voice Handicap Index Applied to Young Adult Male Smokers

Voice performance is an inextricable key factor of everyday life. Obviously, the deterioration of voice quality can cause various problems to human communication and can therefore reduce the performance of social skills (relevant to voice). The deterioration could be originated from changes inside the system of the vocal tract and larynx. Various prognostic methods exist, and among them is the Voice Handicap Index (VHI). This tool includes self-reported questionnaires, used for determining the cutoff points of total score and of its three domains relevant to young male Greek smokers. The interpretation of the calculated cutoff points can serve as a strong indicator of imminent or future evaluation by a clinician. Consistent with previous calculation, the VHI can also act as a feedback for smokers' voice condition and as monitoring procedure toward smoking cessation. Specifically, the sample consisted of 130 male nondysphonic smokers (aged 18-33 years) who all participated in the VHI test procedure. The test results (through receiver operating characteristic analysis) concluded to a total cutoff point score of 19.50 (sensitivity: 0.838, 1-specificity: 0). Also, in terms of constructs, the Functional domain was equal to 7.50 (sensitivity: 0.676, 1-specificity: 0.032), the Physical domain was equal to 7.50 (sensitivity: 0.706, 1-specificity: 0.032), and the Emotional domain was equal to 6.50 (sensitivity: 0.809, 1-specificity: 0.048).

Voice Handicap Index and Interpretation of the Cutoff Points Using Receiver Operating Characteristic Curve as Screening for Young Adult Female Smokers

The relationship between smoking and alterations of the vocal tract and larynx is well known. This pathology leads to the degradation of voice performance in daily living. Multiple assessment methods of vocal tract and larynx have been developed, and in recent years they were enriched with self-reported questionnaires such as Voice Handicap Index (VHI). This study determined the cutoff points of VHI's total score and its three domains for young female smokers in Greece. These estimated cutoff points could be used by voice specialists as an indicator for further clinical evaluation (foreseeing a potential risk of developing a vocal symptom because of smoking habits). A sample of 120 female nondysphonic smokers (aged 18-31) was recruited. Participants filled out the VHI and Voice Evaluation Form. VHI's cutoff point of total score was calculated at the value of 19.50 (sensitivity: 0.780, 1-specificity: 0.133). Specifically, the construct domain of functional was 7.50 (sensitivity: 0.900, 1-specificity: 0.217), for physical it was 8.50 (sensitivity: 0.867, 1-specificity: 0.483), and for emotional it was 7.50 (sensitivity: 0.833, 1-specificity: 0.200) through the use of receiver operating characteristic. Furthermore, VHI could be used as a monitoring tool for smokers and as a feedback for smoking cessation.

Investigating the Effects of Smoking on Young Adult Male Voice by Using Multidimensional Methods

OBJECTIVES

Smoking is one of the most common harmful habits in the world, especially common among young adult male population in Turkey. The purpose of this study was to evaluate the effect of smoking on the young adults' male voice using multidimensional voice assessment methods.

STUDY DESIGN

This is a case-control study.

METHODS

The study included 109 young adult men, 51 nonsmokers and 58 smokers between the ages of 20 and 34 years. The voice evaluation protocol consisted of voice handicap index (VHI), maximum phonation time (MPT), and perceptual, acoustic, and videostroboscopic analyses.

RESULTS

A statistically significant increase for physical, physiological, and total scores of VHI was found in smokers group (P < 0.05). MPT showed significantly lower values among smokers (P < 0.05). There were no significant changes in perceptual analysis of voice samples between smoker and nonsmoker groups. There were no significant changes in any of the acoustic parameters between smoker and nonsmoker groups. Results of videostroboscopic analysis showed significant relationships between smoking and increased vocal fold erythema (P < 0.05). In addition, significantly asymmetry, amplitude, and periodicity abnormality of vocal fold movements were observed in smoker group during phonation (P < 0.05).

CONCLUSIONS

The results of this study indicate that observable signs of laryngeal irritation and disturbed phonatory physiology occur even in young adults with relatively brief smoking habits. Subjective symptoms of smoking on voice appear to occur earlier than objective findings.

The Effect of Moving Window on Acoustic Analysis

OBJECTIVE

To investigate the effects of the moving window method on acoustic measures and discrimination ability between normal and disordered voices.

METHODS

Fifty-three normal voices and 50 disordered voices were recruited. Three selection methods, the moving window method, the mid-vowel method, and the whole vowel method, were applied to each raw audio signal to determine the most stable segment of each signal. Acoustic parameters such as percent jitter, percent shimmer, signal-to-noise ratio (SNR), cepstral peak prominence (CPP), and correlation dimension (D2) were calculated. The Wilcoxon test was used to compare the stability of these segments across different methods. An artificial neural network was used for estimating how well disordered voices were discriminated from normal ones.

RESULTS

Segments selected using the moving window method were more stable than those selected using the other two methods, meaning lower perturbation and nonlinear dynamic measurements as well as higher SNR and CPP values. The discrimination accuracy rate for the moving window method was 91.90 ± 8.73%, whereas the mid-vowel method and the whole vowel method were 72.34 ± 12.94% and 70.34 ± 5.24%, respectively.

CONCLUSION

The moving window method is capable of providing a more stable audio segment and can discriminate disordered voices from normal ones more effectively.

Is the speaking fundamental frequency in females related to body height?

The aim of the study was to determine the impact of body height on speaking fundamental frequency (SF0) while controlling for as many as possible influencing factors such as habits, biophysical conditions, medication, diseases, and others. Fifty-eight females were analyzed during spontaneous speech (i.e. explaining driving directions or a cooking recipe) of at least 60 seconds at comfortable pitch and loudness. The subjects showed a moderate negative and significant correlation between body height and SF0 (r = -0.40, P = 0.002). With r(2) = 0.16, however, a reasonable portion (16%) of the variance in SF0 is explained by the variance in body height. In comparison with other factors for which a correlation with SF0 was mentioned in literature (hypothyrodism, hemodialysis, auditory-maleness after female-to-male transsexualism, body weight, body mass index, and body fat), body height accounted for most of the proportion of SF0 in females. It is therefore possible to validate body height as a factor to account for in clinical F0 measurement.

Nonlinear analyses of elicited modal, raised, and pressed rabbit phonation

OBJECTIVES/HYPOTHESIS

The purpose of this study was to use nonlinear dynamic analysis methods such as phase space portraits and correlation dimension (D2) as well as descriptive spectrographic analyses to characterize acoustic signals produced during evoked rabbit phonation.

METHODS

Seventeen New Zealand white breeder rabbits were used to perform the study. A Grass S-88 stimulator (SA Instrumentation, Encinitas, CA) and constant current isolation unit (Grass Telefactor, model PSIU6; West Warwick, RI) were used to provide electrical stimulation to laryngeal musculature, and transglottal airflow rate and stimulation current (mA) were manipulated to elicit modal, raised intensity, and pressed phonations. Central 1 second portions of the most stable portion of the acoustic waveform for modal, raised intensity, and pressed phonations were edited and then analyzed via phase space portraits, Poincaré sections, and the estimation of the D2. In an attempt to limit the effects of the highly variable and nonstationary characteristics of some of the signals being analyzed, D2 analysis was also performed on the most stable central 200-millisecond portion of the acoustic waveform. Descriptive analysis of each phonation was also conducted using sound spectrograms.

RESULTS

Results showed that the complexity of phonation and the subsequent acoustic waveform is increased as transglottal airflow rate and degree of glottal adduction are manipulated in the evoked rabbit phonation model. In particular, phonatory complexity, as quantified via D2 analyses and demonstrated via spectrographic characteristics, increases from "modal" (ie, phonation elicited at just above the phonation threshold pressure) to raised intensity (phonation elicited by increasing transglottal airflow rate) to pressed (phonation elicited by increasing the stimulation current delivered to the larynx). Variations in a single dynamic dimension (airflow rate or adductory force) resulted in significantly increased productions of nonlinear phenomenon, including bifurcations from periodicity to regions of subharmonic content, fundamental frequency, and harmonic jumps, and evidence of periodicity within aperiodic regions ("chaos").

CONCLUSIONS

The evoked rabbit phonation model described in this study allows for the elicitation of various types of phonations under controlled conditions and, therefore, has the potential to provide insight regarding important variables that may elicit examples of nonlinear phenomena such as subharmonics and deterministic chaos.

Voice complaints among public transport workers in the metropolitan region of Belo Horizonte, Brazil

OBJECTIVE

To investigate the prevalence of voice complaints among bus transport workers in a metropolitan area in Brazil and examine whether sociodemographic and occupational factors were associated with this outcome. This study is part of a larger study that investigated the working conditions and health of drivers and conductors of urban transportation.

METHODS

The sample size (1,607 participants) was calculated by means of quotas and was stratified according to occupation (drivers and conductors) in the bus companies of Belo Horizonte, Betim and Contagem. Face-to-face interviews were facilitated by means of a digital questionnaire, applied by the interviewer using a netbook. The outcome variable was constructed from combining the responses to the following two questions: (1) Over the last two weeks, have you felt tired when speaking? (no/sometimes/every day). (2) Over the last two weeks, have you noticed any worsening of your voice quality? (no/sometimes/every day). Sociodemographic, lifestyle, occupational characteristic and health situation data were gathered.

RESULTS

The prevalence found was 29% overall: 24% for drivers and 34% for conductors. Attention was drawn to positive associations with the function of conductor and with reports of exposure to vibration and thermal discomfort. Among the individual factors, only female gender reached statistical significance.

CONCLUSION

Risk factors exist that justify interventions to promote voice health within the urban transport sector under study. It would be appropriate to investigate whether vibration of the whole body would influence the functioning and morphology of the larynx.

Objective and subjective evaluation of larynx in smokers and nonsmokers: a comparative study

The deleterious effects of smoking on laryngeal mucosa are indisputable. Smoking not only causes histologic (microscopic) alterations in the vocal fold epithelium but also affect the acoustic property of voice. The goal of this study was to determine the effects of smoking on the laryngeal structures and phonatory physiology via videostroboscopy, acoustic voice analysis and electroglottography. Cross-sectional and observational study was carried out in Department of ENT, Pt. J. N. M. Medical College, Raipur, in 100 male volunteers (50 smokers and 50 nonsmokers) between the ages of 18 and 60 years with no voice complaints. All subjects were analyzed for detailed history and underwent videostroboscopic, acoustic voice analysis and electroglottographic examination. Videostroboscopic examination results showed significant relationships between smoking and abnormal vocal fold edge, abnormal texture, edema, erythema, abnormal mucosal cover, abnormal phase symmetry and abnormal pliability/stiffness. Voice analysis showed that smoking has a clear effect on some acoustic voice and electroglottographic parameters. The parameters most commonly affected by smoking are fundamental frequency (F0), jitter, shimmer, F0 tremor, normalized noise energy, signal noise ratio, maximum phonation time (MPT), s/z ratio, opening rate and closing rate. The results indicate that smoking has a significant effect on laryngeal structures and phonatory physiology.