Effects of Muscle Tension Dysphonia on Tone Phonation: Acoustic and Perceptual Studies in Vietnamese Female Teachers

Muscle tension dysphonia (MTD) is a hyperfunctional voice disorder commonly seen in professional voice users. To date, published acoustic studies of this disorder have mainly focused on nontonal language speakers, and no publication has documented its impact on lexical tone characteristics. In this study, we examined whether and how this voice disorder affected acoustically and perceptually the characteristics of tones in Vietnamese teachers. Voice data were obtained from 42 Vietnamese female primary school teachers diagnosed with MTD and 30 vocally healthy teachers. Tonal data were analyzed using Computerized Speech Lab (CSL-4300B) and Speech Analyzer. Parameters analyzed included the two most important acoustic cues in Vietnamese tones, that is, tonal fundamental frequency (F₀) and laryngealization. Tonal F₀ was assessed using a factorial analysis of variance with group and career durations as independent variables. Tonal samples were also perceptually assessed by a panel of native speakers of the same dialect. The results showed that MTD lowered tonal F₀ in high tones and tones with extensive fundamental frequency variation. There was also a significant main effect for career duration; in MTD group, tonal F₀ was lower in teachers with longer career duration. The teachers with MTD showed different patterns of laryngealization compared with the control group. Tone perception was poorer for tones with extensive fundamental frequency variation and without a typical phonation type. The results in this group of teachers supported our hypothesis that MTD impairs lexical tone phonation.     

The control of air flow during loud soprano singing

Previous research on the special characteristics of the professional singing voice has at least partially explained how singers can commonly use much higher lung pressures than nonsingers without vocal damage or excessive air flow during the voiced sounds. In this study, the control of air flow during the unvoiced consonants is examined for an operatic-style soprano. It was found that this singer could maintain a low average air flow during the consonants even though the lung pressure reached values over five times those used during normal conversational speech. The air flow was kept low primarily by the use of a number of mechanisms involving rapid, accurate, coordinated valving of the air flow at the point of articulation and at the glottis.     

Long-Term Outcome of Hyperfunctional Voice Disorders Based on a Multiparameter Approach

SUMMARY: The purpose of this study is to determine the long-term voice outcome (6.1 years after a well-defined voice treatment program) of hyperfunctional voice disorders in 27 subjects. All patients showed a muscle tension pattern type I (MTP I). Perceptual ratings, aerodynamic and acoustical analyses, Voice Handicap Index (VHI) value, and a determination of the Dysphonia Severity Index (DSI) were performed. The laryngovideostroboscopic images indicated that 51% of the subjects still show pathological laryngological findings. The negative evolution of the DSI from -1 to -3.2 is in agreement with this finding. Analysis of the components of the DSI shows that the main responsible variable for this negative change is the lowest intensity (I-low) that increased with 8.1 dB, indicating that subjects generally speak too loud, which is a typical problem for vocal hyperfunction. The VHI-score indicates an unimportant psychosocial impact of the voice disorder. The more objective and laryngostroboscopic findings indicate a chronic situation for a substantial part of the subjects and even a worse situation for some of them. Whether the long-term voice outcome results can be changed with the insertion of several follow-up voice rehabilitation sessions over the years remains unanswered and is a subject for further research.     

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.     

Protocol Challenges for On-the-Job Voice Dosimetry of Teachers in the United States and Finland

The occupational voice use of teachers has been an important research topic over the last 10 years. However, data collection on vocal loading in teachers at and away from the workplace poses significant challenges to the research protocol. The challenges include recruitment of subjects, voice data collection on the job, and subject compliance and retention. The present article offers recommendations for coping with these protocol difficulties. The recommendations are based on the authors' experiences with long-term, on-the-job voice dosimetry of large subject groups of teachers in the United States and Finland.     

Pedagogical Efficiency of Melodic Contour Mapping Technology as it Relates to Vocal Timbre in Singers of Classical Music Repertoire

The purpose of this investigation was to ascertain the pedagogical viability of computer-generated melodic contour mapping systems in the classical singing studio, as perceived by their resulting effect (if any) on vocal timbre when a singer's head and neck remained in a normal singing posture. The evaluation of data gathered during the course of the study indicates that the development of consistent vocal timbre produced by the classical singing student may be enhanced through visual/kinesthetic response to melodic contour inversion mapping, as it balances the singer's perception of melodic intervals in standard musical notation. Unexpectedly, it was discovered that the system, in its natural melodic contour mode, may also be useful for teaching a student to sing a consistent legato line. The results of the study also suggest that the continued development of this new technology for the general teaching studio, designed to address standard musical notation and a singer's visual/kinesthetic response to it, may indeed be useful.     

复杂声音信号基频检测和处理的一种方法及实例

周期性信号基频的检测具有重要的意义，通常的硬件检测方法是采用过零比较器或施密特触发器等电路对输入信号进行整形，从而获得基频脉冲。当信号波形复杂时，这种检测方法就会失准。本文提出了一种新的硬件检测方法有效转变点实时基频检测法，它用两个适当电平切割被测信号，从而获得有效的零点，解决了信号复杂时过零点增多的现象，文内并给出了一个检测人声基频进而实现人声向乐器声转化的应用实例。     

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.     

The treatment of essential voice tremor with botulinum toxin A: A longitudinal case report

The purpose of this study was to evaluate the effects of bilateral botulinum toxin injection into the thyroarytenoid (TA) muscles of a patient with essential voice tremor. Acoustic and aerodynamic data were collected weekly over a 16-week period. Flexible nasolaryngoscopy was performed prior to injection and 2, 6, 10, and 16 weeks postinjection. Perceptual analyses of the acoustic and nasolaryngoscopic data were performed. A reduction in frequency tremor and, to a lesser extent, amplitude tremor was observed during the 1-10 week period. Estimated laryngeal resistance decreased after injection and was accompanied in perceptual measures by a reduction in vocal effort, laryngeal tremor, and supraglottic hyperfunction. Essential voice tremor can be successfully attenuated with bilateral percutaneous injection of botulinum toxin A into the vocalis muscle.