Cepstral and Perceptual Investigations in Female Teachers With Functionally Healthy Voice

PurposeThe present study aimed at measuring the smoothed and non-smoothed cepstral peak prominence (CPPS and CPP) in teachers who considered themselves to have normal voice but some of them had laryngeal pathology. The changes of CPP, CPPS, sound pressure level (SPL) and perceptual ratings with different voice tasks were investigated and the influence of vocal pathology on these measures was studied.MethodEighty-four Finnish female primary school teachers volunteered as participants. Laryngoscopically, 52.4% of these had laryngeal changes (39.3% mild, 13.1% disordered). Sound recordings were made for phonations of comfortable sustained vowel, comfortable speech, and speech produced at increased loudness level as used during teaching. CPP, CPPS and SPL values were extracted using Praat software for all three voice samples. Sound samples were also perceptually evaluated by five voice experts for overall voice quality (10 point scale from poor to excellent) and vocal firmness (10 point scale from breathy to pressed, with normal in the middle).ResultsThe CPP, CPPS and SPL values were significantly higher for vowels than for comfortable speech and for loud speech compared to comfortable speech (P < 0.001). Significant correlations were found between SPL and cepstral measures. The loud speech was perceived to be firmer and have a better voice quality than comfortable speech. No significant relationships of the laryngeal pathology status with cepstral values, perceptual ratings, or voice SPLs were found (P > 0.05).ConclusionNeither the acoustic measures (CPP, CPPS, and SPL) nor the perceptual evaluations could clearly distinguish teachers with laryngeal changes from laryngeally healthy teachers. Considering no vocal complaints of the subjects, the data could be considered representative of teachers with functionally healthy voice.     

Treatment Outcomes for Professional Voice Users

Professional voice users comprise 25% to 35% of the U.S. working population. Their voice problems may interfere with job performance and impact costs for both employers and employees. The purpose of this study was to examine treatment outcomes of two specific rehabilitation programs for a group of professional voice users. Eighteen professional voice users participated in this study; half had complaints of throat pain or vocal fatigue (Dysphonia Group), and half were found to have benign vocal fold lesions (Lesion Group). One group received 5 weeks of expiratory muscle strength training followed by six sessions of traditional voice therapy. Treatment order was reversed for the second group. The study was designed as a repeated measures study with independent variables of treatment order, laryngeal diagnosis (lesion vs non-lesion), gender, and time. Dependent variables included maximum expiratory pressure (MEP), Voice Handicap Index (VHI) score, Vocal Rating Scale (VRS) score, Voice Effort Scale score, phonetogram measures, subglottal pressures, and acoustic and perceptual measures. Results showed significant improvements in MEP, VHI scores, and VRS scores, subglottal pressure for loud intensity, phonetogram area, and dynamic range. No significant difference was found between laryngeal diagnosis groups. A significant difference was not observed for treatment order. It was concluded that the combined treatment was responsible for the improvements observed. The results indicate that a combined modality treatment may be successful in the remediation of vocal problems for professional voice users.     

Voice Therapy Outcome—A Randomized Clinical Trial Comparing Individual Voice Therapy,Therapy in Group,and Controls Without Therapy

ObjectiveA stumbling-block in voice therapy is how the patient will be able to apply the new voice technique in everyday life. Possibly this generalization process could be facilitated by giving voice therapy in group because of the natural forum for training voice-to-speech early in communication between the patients in a group setting. The aim of the study was to compare treatment results from individual voice therapy and voice therapy in group, at several time points and in comparison to patients with no voice therapy.MethodsA randomized treatment study was performed with 77 consecutive patients diagnosed with a functional voice disorder. Thirty-one patients were randomized to individual and group therapy, respectively, and 15 patients to no therapy. The assessments included standardized voice recording and registration of voice range profile (VRP), answering Voice handicap index (VHI) and visual analogue scales for self-hoarseness and self-vocal fatigue, and perceptual voice evaluation by speech-language pathologist. The assessments were performed before, direct after therapy, and three months later in all groups. The 2 therapy groups were also assessed 12 months after therapy.ResultsAll VHI scores as well as the self-ratings of hoarseness and vocal fatigue, and the perceptual evaluation of voice quality and maximum VRP improved significantly in both therapy groups 3 months after treatment and at 12 months follow-up. There were no significant changes in the control group, with the exception of decreased self-rated hoarseness and increased maximum VRP. Comparisons between treatment groups showed significant larger improvement after group therapy for VHI physical subscale at 12 months, as well as significant lower VHI total score at all measurement sessions and lower subscale scores at 12 months. There were no differences between treatment groups in self-hoarseness or self-vocal fatigue and no difference in perceptual voice quality or VRP. Comparison between controls and treatment groups showed significant larger change in treatment groups from baseline to three months in VHI total and to end of therapy in functional subscale. Treatment groups also showed significant lower scores than controls at each measurement session, for VHI total and physical subscale as well as lower degree of perceptual aberration of voice quality and vocal fatigue, at three months follow-up.ConclusionsThis study shows long-term improvement from behavioral voice therapy, particularly in a group setting. The results indicate the importance of early transfer-to-speech and late posttherapy test to capture whether the goal of voice therapy was fulfilled or not for the patients.     

Presbyphonia as an Individual Process of Voice Change

ObjectiveThe aim of the study was to determine the individual variability of the severity of dysphonia in the population of older women and men using the initial perceptual voice assessment (GRBAS) and objective diagnosis of the clinical form of Presbyphonia with laryngeal visualization technique (High-Speed Digital Imaging [HSDI]) and acoustic voice analysis (Diagnoscope Specjalista).MethodsThe study included 302 elderly women and men. Application of perceptual GRBAS scale allowed to extract 230 subjects with voice disorders (Group I). Remaining 72 elderly subjects without the symptoms of dysphonia consisted Group II. Group III included 50 subjects with euphonic voice. In the assessment of dysphonia, visualization technique (HSDI) as well as acoustic method (Diagnoscope Specjalista). The observation of real vibration of vocal folds using HSDI technique and HS camera allowed to examine symmetricity (Shaw-Deliyski scale), periodicity and amplitude of vibration, Mucosal Wave (MW) morphology, Glottal Closure Type, and value of Open Quotient (OQ). Acoustic analysis allowed to assess value of Fundamental Frequency (F0), Maximum Phonation Time (MPT) as well as Jitter, Shimmer, Noise-to-Harmonics Ratio (NHR) parameters. Narrowband Spectrography was performed.ResultsHSDI technique allowed to register in elderly women with voice disorders a mild asymmetry and aperiodicity of vibrations, MW reduction, amplitude increase and glottal insufficiency in the posterior segment of glottis which indicated edematous changes in the larynx. In 90% of men in this group, moderate asymmetry and aperiodicity were observed as well as amplitude decrease, significant limitation of MW and glottal insufficiency in the middle segment of the glottis which indicated atrophic changes in the larynx. In remaining 10% of men, amplitude of vibration was increased which indicated the existence of hypofunctional dysphonia. Objective confirmation of glottal insufficiency in women with edematous changes was high value of OQ in posterior segment of the glottis registered with HSDI technique. In men with larynx atrophy, the value of OQ was the highest in the middle segment of the glottis. Glottal insufficiency, especially in the middle segment, coexisted with the increase of NHR parameter observed in acoustic examination and with numerous nonharmonic components in the scope of high frequencies revealed in narrowband spectrography, especially in men with larynx atrophy. What is more, in men, the increase of F0 and reduction of MPT was registered. In women with edematous changes of the larynx, acoustic analysis revealed decrease of F0 value, increase of Jitter, Shimmer, NHR as well as reduction of MPT. Narrowband sopectrography revealed not only harmonic components but also nonharmonics in the range of low, medium, and high frequencies.ConclusionsThe course of Presbyphonia varies individually in the elderly. In many subjects, the process of aging does not influence the quality of voice. Crucial importance in the diagnosis of Presbyphonia is assigned to High-Speed Digital Imaging technique which confirms the existence of edematous changes in the larynx in women as well as atrophy and hypofunctional dysphonia in men. The acoustic examination of voice confirmed the individual variability of the severity of Presbyphonia in the elderly depending on the clinical form of dysphonia determined by the gender of the diagnosed person.     

Perceptual Evaluation of Voice Disorder in Children Who Have Had Laryngotracheal Reconstruction Surgery and the Relationship Between Clinician Perceptual Ratingof Voice Quality and Parent Proxy/Child Self-Report of Voice-Related Quality of Life

Reliability of the GRBAS tool for perceptual evaluation of paediatric voice disorder is measured in this study of children with a history of laryngotracheal reconstruction surgery (LTR). Additionally, the relationship between parent proxy/child self-report of voice-related quality of life with clinician perceptual rating of voice quality is analysed. Eleven children with a history of LTR provided voice recordings following the stimuli set by the CAPE-V protocol. Subjective impact of voice quality on life was measured using the paediatric voice-related quality of life questionnaire. Four trained judges rated the sound files according to both the GRBAS and CAPE-V protocol. Intra-class correlation coefficients were high for both intra-rater and inter-rater judgments across all parameters of the GRBAS protocol, and a strong correlation was found between the grade rating of the GRBAS and the overall severity rating of the CAPE-V. Some elements of parent proxy reporting of voice-related quality of life were significantly negatively correlated with clinician perceptual rating of voice quality, while there was no significant relationship between child self-report and clinician perceptual rating.     

Correlation of VHI-10 to Voice Laboratory Measurements Across Five Common Voice Disorders

ObjectiveTo correlate change in Voice Handicap Index (VHI)-10 scores with corresponding voice laboratory measures across five voice disorders.Study DesignRetrospective study.MethodsOne hundred fifty patients aged >18 years with primary diagnosis of vocal fold lesions, primary muscle tension dysphonia-1, atrophy, unilateral vocal fold paralysis (UVFP), and scar. For each group, participants with the largest change in VHI-10 between two periods (T_A and T_B) were selected. The dates of the VHI-10 values were linked to corresponding acoustic/aerodynamic and audio-perceptual measures. Change in voice laboratory values were analyzed for correlation with each other and with VHI-10.ResultsVHI-10 scores were greater for patients with UVFP than other disorders. The only disorder-specific correlation between voice laboratory measure and VHI-10 was average phonatory airflow in speech for patients with UVFP. Average airflow in repeated phonemes was strongly correlated with average airflow in speech (r = 0.75). Acoustic measures did not significantly change between time points.ConclusionsThe lack of correlations between the VHI-10 change scores and voice laboratory measures may be due to differing constructs of each measure; namely, handicap versus physiological function. Presuming corroboration between these measures may be faulty. Average airflow in speech may be the most ecologically valid measure for patients with UVFP. Although aerodynamic measures changed between the time points, acoustic measures did not. Correlations to VHI-10 and change between time points may be found with other acoustic measures.     

Multiparametric Evaluation of Dysphonic Severity

SUMMARY: In recent years, the multiparametric approach for evaluating perceptual rating of voice quality has been advocated. This study evaluates the accuracy of predicting perceived overall severity of voice quality with a minimal set of aerodynamic, voice range profile (phonetogram), and acoustic perturbation measures. One hundred and twelve dysphonic persons (93 women and 19 men) with laryngeal pathologies and 41 normal controls (35 women and six men) with normal voices participated in this study. Perceptual severity judgement was carried out by four listeners rating the G (overall grade) parameter of the GRBAS scale. The minimal set of instrumental measures was selected based on the ability of the measure to discriminate between dysphonic and normal voices, and to attain at least a moderate correlation with perceived overall severity. Results indicated that perceived overall severity was best described by maximum phonation time of sustained /a/, peak intraoral pressure of the consonant-vowel /pi/ strings production, voice range profile area, and acoustic jitter. Direct-entry discriminant function analysis revealed that these four voice measures in combination correctly predicted 67.3% of perceived overall severity levels.     

Positive Effects of Manual Circumlaryngeal Therapy in the Treatment of Muscle Tension Dysphonia (MTD): Long Term Treatment Outcomes

IntroductionManual circumlaryngeal therapy (MCT) aims to correct laryngeal position and relax (para) laryngeal and cervical muscles resulting in improved voice quality. The goal of the current study was to further verify long-term effects of MCT in the treatment of Muscle Tension Dysphonia (MTD) patients based on acoustic findings and perceptual judgments.MethodTwenty-eight adult female patients who had been referred to the speech therapy clinic of Khatam Hospital, Zahedan city, participated in this study. Manual circumlaryngeal therapy was undertaken. There were 15 therapy sessions, three sessions per week, each with duration of 30 minutes. Pre- and post-treatment audio recordings of sustained vowels, selected sentences, and connected speech samples were submitted to auditory-perceptual and acoustical analysis to assess the long-term (6-months) effects of the 15 treatment program.ResultsAcoustically, Harmonic to Noise Ratio (HNR) increased and perturbation (Jitter and Shimmer) measures decreased, and perceptually, the subjective CAPE-V ratings improved in all patients.ConclusionThese results suggest that MCT can be an effective method for voice rehabilitation in patients with MTD and the changes due to the therapy were persistent over a 6-month duration following the termination of treatment sessions.     

Reliability of Speaking and Maximum Voice Range Measures in Screening for Dysphonia

Speech range profile (SRP) is a graphical display of frequency-intensity occurring interactions during functional speech activity. Few studies have suggested the potential clinical applications of SRP. However, these studies are limited to qualitative case comparisons and vocally healthy participants. The present study aimed to examine the effects of voice disorders on speaking and maximum voice ranges in a group of vocally untrained women. It also aimed to examine whether voice limit measures derived from SRP were as sensitive as those derived from voice range profile (VRP) in distinguishing dysphonic from healthy voices. Ninety dysphonic women with laryngeal pathologies and 35 women with normal voices, who served as controls, participated in this study. Each subject recorded a VRP for her physiological vocal limits. In addition, each subject read aloud the "North Wind and the Sun" passage to record SRP. All the recordings were captured and analyzed by Soundswell's computerized real-time phonetogram Phog 1.0 (Hitech Development AB, T?by, Sweden). The SRPs and the VRPs were compared between the two groups of subjects. Univariate analysis results demonstrated that individual SRP measures were less sensitive than the corresponding VRP measures in discriminating dysphonic from normal voices. However, stepwise logistic regression analyses revealed that the combination of only two SRP measures was almost as effective as a combination of three VRP measures in predicting the presence of dysphonia (overall prediction accuracy: 93.6% for SRP vs 96.0% for VRP). These results suggest that in a busy clinic where quick voice screening results are desirable, SRP can be an acceptable alternate procedure to VRP.     

Outcome of laryngeal manual therapy in four Dutch adults with persistent moderate-to-severe vocal hyperfunction: a pilot study

A relatively new management strategy for the treatment of voice disorders is the use of laryngeal manual therapy. The main purpose of the present pilot study is to document the outcome of vocal quality after a well-defined laryngeal manual therapy (LMT) program. Four Dutch professional voice users with a persistent moderate or severe muscle tension dysphonia were studied pretreatment (1 week before LMT) and posttreatment (1 week) after completion of manual therapy (25 sessions). These subjects had received several months of traditional voice therapy, without any success. To measure and compare, the effect of LMT objective and subjective assessment techniques were used. Perceptual voice assessment included a perceptual rating of the voice using the GRBAS scale. Furthermore, the vocal quality in this population was modeled by means of the Dysphonia Severity Index (DSI). All of the subjects selected for LMT showed improvement in perceptual vocal quality and DSI values. As the DSI is a weighted variable including aerodynamic and acoustic measures, small improvements (closer to 5) are very indicative of vocal quality improvement.¹ The use of LMT in professional voice users with persistent moderate-to-severe muscle tension dysphonia, especially in some subjects who have not responded to traditional voice therapy, is supported by this pilot study.     

Perceptual evaluation of voice quality and its correlation with acoustic measurements

To determine whether a correlation exists between the Grade, Roughness, Breathiness, Aesthenia, Strain (GRBAS) scale (a subjective measure of voice) and the Multi-Dimensional Voice Program (MDVP) scale (an objective measure of voice). A retrospective review of 37 voice patients (12 male/25 female) was conducted. Each voice was perceptually evaluated using the GRBAS scale by an experienced speech pathologist and acoustically analyzed using the MDVP scale. Statistical analysis using a multivariate regression model identified a significant correlation between the noise-related parameters of MDVP and the components of the GRBAS scale. Grade correlated with voice turbulence index (VTI), noise harmonic ratio (NHR), and soft phonation index (SPI). Roughness correlated with NHR only. Breathiness correlated with SPI only. Aesthenia also correlated with SPI only. Of the 19 acoustic variables measured by the MDVP system, only three noise parameters significantly correlated with the GRBAS perceptual voice analysis. Perhaps "noise" is the perceived acoustical quality of the dysphonic voice. A voice quantifying measure such as a "voice index score" could be proposed using the GRBAS scoring and the three clinically relevant MDVP values following further studies.     

Voice characteristics, effects of voice therapy, and long-term follow-up of contact granuloma patients

This study evaluates the laryngoscopic findings and voice characteristics of male contact granuloma patients before and after voice therapy and at a follow-up about 9 years later. Pre- and posttherapy recordings as well as follow-up recordings were made for 19 granuloma patients. Pretherapy revealed the most salient perceptual voice characteristics were low pitch, monotony, and a high degree of vocal fry and hyperfunction. Interjudge reliability for these traits was high. Immediately following therapy the healed patients (n = 10) had a decrease in hyperfunction, vocal fry, and monotony, while the unhealed patients (n = 9) had an increase in hyperfunction and vocal fry decreased only marginally. Monotony decreased significantly in this group. As regards the acoustic analyses, no significant differences were found in mean fundamental frequency (F₀) or perturbation. At the follow-up assessment 4 patients had granuloma while 15 had normal laryngeal status. Perceptually their voice characteristics resembled those pretherapy independently of the laryngeal findings. The results suggest that reduced hyperfunction and decreased vocal fry may create better circumstances for the healing process at the posterior glottis.     

Voice of Postradiotherapy Nasopharyngeal Carcinoma Patients: Evidence of Vocal Tract Effect

This study was aimed at identifying acoustic and physiological measures useful for monitoring voice changes in postnasopharyngeal patients with nonlaryngeal malignancies, and providing evidences of vocal tract effect on voice through comparisons between individuals with and without intact vocal tract. Simultaneous acoustic-electroglottographic signals recorded during phonation of vowels /i/ and /a/ sustained at habitual, high, and low pitch levels were compared among 10 postradiotherapy patients with nasopharyngeal carcinoma (NPC), 10 voice patients (VPs) with intact vocal tract, and 10 healthy individuals with normal voice (NORM). Results from a series of discriminant analyses revealed that the NPC group generally exhibited lower signal-to-noise (SNR) and open quotient (OQ) and higher Formant 1 frequency (F(1)) and speed quotient (SQ) than the NORM group. Unlike both VP and NORM groups, the NPC group failed to show a pitch effect on all voice measures, including OQ, SQ, percent jitter, percent shimmer, and SNR, suggesting an effect of radiotherapy and/or vocal tract on laryngeal behaviors. For the vowel /i/, on the other hand, only the NPC and NORM groups showed a pattern of pitch-dependent F(1) raising, a reflection of increased pharyngeal narrowing. These findings suggested that the pitch effect on laryngeal behaviors differed not only between individuals with intact vocal tract and those without but also between those with structural and dynamic changes of vocal tract.     

The Voice Performance After Septoplasty With Surgical Efficacy Demonstrated Through Acoustic Rhinometry and Rhinomanometry

ObjectiveTo demonstrate the surgical efficacy of septoplasty using acoustic rhinometry (AR) and anterior rhinomanometry (ARM) and to evaluate the effect of septoplasty on voice performance through subjective voice analysis methods.Materials and MethodsThis prospective study enrolled a total of 62 patients who underwent septoplasty with the diagnosis of deviated nasal septum. Thirteen patients with no postoperative improvement versus preoperative period as shown by AR and/or ARM tests and three patients with postoperative complications and four patients who were lost to follow-up were excluded. As a result, a total of 42 patients were included in the study. Objective tests including AR, ARM, acoustic voice analysis and spectrographic analysis were performed before the surgery and at 1 month and 3 months after the surgery. Subjective measures included the Nasal Obstruction Symptom Evaluation questionnaire to evaluate surgical success and Voice Handicap Index-30 tool for assessment of voice performance postoperatively, both completed by all study patients.ResultsAmong acoustic voice analysis parameters, F0, jitter, Harmonics-to-Noise Ratio values as well as formant frequency (F1-F2-F3-F4) values did not show significant differences postoperatively in comparison to the preoperative period (P > 0.05). Only the shimmer value was statistically significantly reduced at 1 month (P < 0.05) and 3 months postoperatively (P < 0.05) versus baseline. Statistically significant reductions in Voice Handicap Index-30 scores were observed at postoperative 1 month (P < 0.001) and 3 months (P < 0.001) compared to the preoperative period and between postoperative 1 month and 3 months (P < 0.05).ConclusionIn this study, first operative success of septoplasty was demonstrated through objective tests and then objective voice analyses were performed to better evaluate the overall effect of septoplasty on voice performance. Shimmer value was found to be improved in the early and late postoperative periods.     

The Effectiveness of Group Therapy for Students With Mild Voice Disorders: A Controlled Clinical Trial

Previous studies of students studying to be teachers have indicated that these students commonly have voice disorders. Ideally, voice disorders should be treated before students start their work as teachers, but the resources for this treatment are often limited. This study examines whether group voice therapy is effective for teacher students. Accordingly, 20 teacher students with mild voice disorders received group voice therapy (in three small groups), whereas 20 students with similar voice disorders served as a control group and consequently did not receive voice therapy. Two out of three outcome measures (perceptual evaluation of voice quality and a questionnaire on the occurrence of vocal symptoms) indicated significant changes in the treatment group compared with the control group. No differences between groups were noted in the laryngeal status. The results suggest that group voice therapy seems to be an effective method to treat students with mild voice disorders.     

Vocal violence in actors: An investigation into its acoustic consequences and the effects of hygienic laryngeal release training

Acoustic analysis techniques were used to investigate the short-term consequences of vocally violent behavior, and to compare voice production before and after training in hygienic laryngeal release (HLR) techniques. Twenty-seven actors ranging in age from 17 to 48 years were audiorecorded before and after multiple productions of 4 vocally violent behaviors: grunting, groaning, sobbing, and shouting. After training in HLR techniques, the experimental protocol was repeated. Audiorecordings of vowels (produced at 3 pitch levels: modal F0, minimum F0, maximum F0) before and after vocal violence, and before and after HLR training, were analyzed using the Multidimensional Voice Program (4305, Kay Elemetrics Corp, Lincoln Park, NJ). After vocal violence, no consistent acoustic changes were detected for voice generated at modal and minimum F0; however, significant increases in both fundamental frequency range and maximum F0 were observed. After training in HLR techniques, acoustic measures sensitive to pitch and amplitude perturbation, and non-harmonic noise, improved across pitch levels. The results also indicated that vocal training does defend the laryngeal system from undesirable changes related to vocally violent maneuvers that might surface at the extremes of an actor's pitch range. Because the HLR technique used in this investigation was multimodal, interesting questions are raised regarding which aspect of training is primarily responsible for the observed effects. Further study is required to identify such factors.     

Evaluation of Voice Quality in Patients With Vocal Fold Polyps: The Size of a Polyp Matters or Does it?

ObjectiveThis study aimed to investigate the correlation between morphological features of vocal fold polyps (VFPs) and subjective/objective voice parameters.MethodsPerceptual evaluations, aerodynamic and acoustic tests were performed on 47 patients with VFPs. Still images were captured from video and the morphological features associated with the size of VFP were quantified. To reveal the correlation between size-related morphological features (length of polyp base, the ratio of polyp base to vocal fold length, glottal gap area) and objective/subjective parameters of voice, Pearson's and Spearman's tests were carried out.ResultsThis cohort was composed of 30 (63.8 %) male and 17 (36.2%) female patients with the mean age of 45.2 years and 41.3 years, respectively. No correlation was found between the morphological features of VFPs and any of perceptual, aerodynamic and acoustic voice parameters.ConclusionsOur findings indicated that controversies still exist regarding the role of vocal fold polyp morphology in clinical decision making.     

Perceptual and Acoustic Characteristics of Voice Changes in Reflux Laryngitis Patients

The aim of the study was to outline the multidimensional perceptual, subjective, and instrumental acoustic voice changes in the group of reflux laryngitis (RL) patients. Data of multidimensional voice assessment of 108 RL patients and 90 healthy persons of the control group were subjected to comparative analysis. A slight hoarseness according to the GRB (G-grade, R- rough, B-breathy) scale was prevailing in the RL patients group. Statistically significant difference (P < 0.001) between RL patients group and the control group was found of all voice parameters measured, with the patients having worse results--increased mean jitter, shimmer, normalized noise energy, voice handicap index (VHI), and decreased parameters of phonetogram. The results of the study demonstrated that multidimensional voice assessment documented deteriorated voice quality and restricted phonation capabilities in the tested group of RL patients.     

The Relationship Between Cepstral Peak Prominence and Selected Parameters of Dysphonia

Traditional measures of dysphonia vary in their reliability and in their correlations with perceptions of grade. Measurements of cepstral peak prominence (CPP) have been shown to correlate well with perceptions of breathiness. Because it is a measure of periodicity, CPP should also predict roughness. The ability of CPP and other acoustic measures to predict overall dysphonia and the subcategories of breathiness and roughness in pathological voice samples is explored. Preoperative and postoperative speech samples from 19 patients with unilateral recurrent laryngeal nerve paralysis who underwent operative intervention were analyzed by trained listeners and by measures of smoothed CPP (CPPS), noise-to-harmonic ratio (NHR), amplitude perturbation quotient (APQ), relative average perturbation (RAP), and smoothed pitch perturbation quotient (sPPQ). The data were analyzed with bivariate Pearson correlation statistics. Grade of dysphonia and breathiness ratings correlated better with measurements of CPPS than with the other measures. CPPS from samples of connected speech (CPPS-s) best predicted overall dysphonia. None of the measures were useful in predicting roughness.     

Acoustic and Perceptual Appraisal of Vocal Gestures in the Female Classical Voice

Long-term average spectra (LTAS) have identified features in the sounds of singers and have compared different vocal qualities based on energy changes that occur during different vocal tasks. In this study, we compared the perceptual ratings of vocal quality of expert pedagogues with acoustic measures performed on LTAS. Fifteen expert judges rated 24 samples with six repeats of six advanced singing students under two conditions: "optimal" (O), which represented the application of the maximal open throat technique; and "suboptimal" (SO), which represented the application of the reduced open throat technique. LTAS were performed on each singing sample, and two conventional assessments of peak energy height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were calculated on each LTAS. Perceptual scores, SPR, and ER were rank ordered. We then compared perceptual rankings with rankings of acoustic measures (SPR and ER) to assess whether these acoustic measurements matched the perceptual judgments of vocal quality. Although we found the expected significant relationship between SPR and ER, there was no relationship between perceptual ratings of vocal samples or singers based on SPR or ER. These findings suggest that because LTAS measures are not consistent with perceptual ratings of vocal quality, such measurements cannot define a voice of quality. Future research with LTAS to assess vocal quality should consider alternative measures that are more sensitive to subtle differences in vocal parameters.