A Pilot Survey of Vocal Health in Young Singers

The objective of this study was to determine the incidence of vocal problems in young choir singers and to correlate vocal problems with demographic and behavioral information. A questionnaire addressing vocal habits and hygiene was offered to 571 young choir singers, up to 25 years of age, who sing at least weekly; 129 (22.6%) responded. More than one-half of the respondents had experienced vocal difficulty, particularly older adolescents. Detrimental behaviors and circumstances surveyed were not reflective of the incidence of vocal difficulty, except for morning hoarseness, chronic fatigue, insomnia, and female gender after puberty. Voice care professionals should be aware that self-reported voice difficulties are common among young choral singers, especially postpubescent girls, and children with symptoms consistent with reflux (morning hoarseness) and emotional stress (insomnia). Laryngologists should communicate with choral conductors and singing teachers to enhance early identification and treatment of children with voice complaints, and to develop choral educational strategies that help decrease their incidence.     

Mechanical and dynamic aspects of voice production as related to voice therapy and phonosurgery

Laryngeal framework surgery can change the position and tensionof the vocal folds safely without direct surgical intervention in the vocal fold proper. Some 23 years of experience with phonosurgery have proved its usefulness in treating dysphonia related to unilateral vocal fold paralysis, vocal fold atrophy, and pitch-related dysphonias. Meanwhile, much information about the mechanism of voice production has been obtained through intraoperative findings of voice and fiberscopic examination of the larynx . Based on such knowledge together with information obtained through model experiments, the human vocal organ was reconsidered mainly from the mechanical view point, and the roles of voice therapy and singing pedagogy were discussed in relation to phonosurgery. The vocal organ may not be an ideal musical organ and is rather vulnerable, but its potential is enormous.     

Effect of Hydration and Vocal Rest on the Vocal Fatigue in Amateur Karaoke Singers

Karaoke singing is a very popular entertainment among young people in Asia. It is a leisure singing activity with the singer's voice amplified with special acoustic effects in the backdrop of music. Music video and song captions are shown on television screen to remind the singers during singing. It is not uncommon to find participants singing continuously for four to five hours each time. As most of the karaoke singers have no formal training in singing, these amateur singers are more vulnerable to developing voice problems under these intensive singing activities. This study reports the performance of 20 young amateur singers (10 males and 10 females, aged between 20-25 years) on a series of phonatory function tasks carried out during continuous karaoke singing. Half of the singers were given water to drink and short duration of vocal rests at regular intervals during singing and the other half sang continuously without taking any water or rest. The subjects who were given hydration and vocal rests sang significantly longer than those who did not take any water or rest. The voice quality, as measured by perceptual and acoustic measures, and vocal function, as measured by phonetogram, did not show any significant changes during singing in the subjects who were given water and rest during the singing. However, subjects who sang continuously without drinking water and taking rests showed significant changes in the jitter measure and the highest pitch they could produce during singing. These results suggest that hydration and vocal rests are useful strategies to preserve voice function and quality during karaoke singing. This information is useful educational information for karaoke singers.     

Three-dimensional vocal tract imaging and formant structure: varying vocal register, pitch, and loudness

Although advances in techniques for image acquisition and analysis have facilitated the direct measurement of three-dimensional vocal tract air space shapes associated with specific speech phonemes, little information is available with regard to changes in three-dimensional (3-D) vocal tract shape as a function of vocal register, pitch, and loudness. In this study, 3-D images of the vocal tract during falsetto and chest register phonations at various pitch and loudness conditions were obtained using electron beam computed tomography (EBCT). Detailed measurements and differences in vocal tract configuration and formant characteristics derived from the eight measured vocal tract shapes are reported.     

Normative Standards for Vocal Tract Dimensions by Race as Measured by Acoustic Pharyngometry

SUMMARY: Acoustic pharyngometry evaluates the geometry of the vocal tract with acoustic reflections and provides information about vocal tract cross-sectional area and volume from lip to the glottis. Variations in vocal tract diameters are needed for speech scientists to validate various acoustic models and for medical professionals since the advent of endoscopic surgical techniques. Race is known to be one of the most important factors affecting the oral and nasal structures. This study compared vocal tract dimensions of White American, African American, and Chinese male and female speakers. One hundred and twenty healthy adult subjects with equal numbers of men and women were divided among three races. Subjects were controlled for age, gender, height, and weight. Six dimensional parameters of the speakers' vocal tract cavities were measured with acoustic reflection technology (AR). Significant gender and race main effects were found in certain vocal tract dimensions. The findings of this study now provide speech scientists, speech-language pathologists, and other health professionals with a new anatomical database of vocal tract variations for adult speakers from three different races.     

Discrimination of speaker size from syllable phrases

The length of the vocal tract is correlated with speaker size and, so, speech sounds have information about the size of the speaker in a form that is interpretable by the listener. A wide range of different vocal tract lengths exist in the population and humans are able to distinguish speaker size from the speech. Smith et al. [J. Acoust. Soc. Am. 117, 305-318 (2005)] presented vowel sounds to listeners and showed that the ability to discriminate speaker size extends beyond the normal range of speaker sizes which suggests that information about the size and shape of the vocal tract is segregated automatically at an early stage in the processing. This paper reports an extension of the size discrimination research using a much larger set of speech sounds, namely, 180 consonant-vowel and vowel-consonant syllables. Despite the pronounced increase in stimulus variability, there was actually an improvement in discrimination performance over that supported by vowel sounds alone. Performance with vowel-consonant syllables was slightly better than with consonant-vowel syllables. These results support the hypothesis that information about the length of the vocal tract is segregated at an early stage in auditory processing.     

Model-based classification of nonstationary vocal fold vibrations

Classification of vocal fold vibrations is an essential task of the objective assessment of voice disorders. For historical reasons, the conventional clinical examination of vocal fold vibrations is done during stationary, sustained phonation. However, the conclusions drawn from a stationary phonation are restricted to the observed steady-state vocal fold vibrations and cannot be generalized to voice mechanisms during running speech. This study addresses the approach of classifying real-time recordings of vocal fold oscillations during a nonstationary phonation paradigm in the form of a pitch raise. The classification is based on asymmetry measures derived from a time-dependent biomechanical two-mass model of the vocal folds which is adapted to observed vocal fold motion curves with an optimization procedure. After verification of the algorithm performance the method was applied to clinical problems. Recordings of ten subjects with normal voice and ten dysphonic subjects have been evaluated during stationary as well as nonstationary phonation. In the case of nonstationary phonation the model-based classification into "normal" and "dysphonic" succeeds in all cases, while it fails in the case of sustained phonation. The nonstationary vocal fold vibrations contain additional information about vocal fold irregularities, which are needed for an objective interpretation and classification of voice disorders.     

The singing teacher as vocal parent

Vocal parenting is a pedagogical approach that views the teachingof singing to children as a nurturing process. It encompasses the development of fundamentally sound vocal technique, guidance in repertoire selection and performance practices, and concern for the physical, mental, and emotional well-being of the child as a singer, performer, and person. Role-play and storytelling are among the strategies employed to fully integrate vocal technique with the personality of the singer.     

Impact and Prevention of Voice Problems in the Teaching Profession: Embracing the Consumers'' View

Teachers are vulnerable to developing voice problems due to their specific occupational demands during teaching. Information on how the teaching profession is impacted by voice problems and what the profession perceives to be useful information for preventing voice problems is important for health care service providers. A total of 122 subjects from the teaching profession (55 practicing teachers and 67 prospective teachers) were therefore surveyed to ascertain their perception of their voice condition and the impact of voice problems on their communication, social life, personal emotions, and occupation. The results showed that the practicing teachers perceived their voice to be significantly worse than the prospective teachers. In addition, the teachers also faced significantly more difficulties in their daily communication than the prospective teachers. These two groups of subjects believed that information on breathing exercises and specific vocal hygiene strategies would help them prevent voice problems.     

Airflow measurements: Theory and utility of findings

The biomechanical movements of vocal structures are shown to control flow of expiratory air for the production of speech sounds. Laminar and turbulent air flow are discussed as they relate to sound generation. Theoretic and therapeutic utility of air flow profiles in differentiating linguistic contrasts and vocal characteristics are discussed along with considerations of relative utility and accuracy for various flow-measuring devices and strategies.     

Vocal aging and the impact on daily life: a longitudinal study

Longitudinal studies on vocal aging are scarce, and information on the impact of age-related voice changes on daily life is lacking. This longitudinal study reports on age-related voice changes and the impact on daily life over a time period of 5 years on 11 healthy male speakers, age ranging from 50 to 81 years. All males completed a questionnaire on vocal performance in daily life, and perceptual and acoustical analyses of vocal quality and analyses of maximum performance tasks of vocal function (voice range profile) were performed. Results showed a significant deterioration of the acoustic voice signal as well as increased ratings on vocal roughness judged by experts after the time period of 5 years. An increase of self-reported voice instability and the tendency to avoid social parties supported these findings. Smoking males had a lower speaking fundamental frequency compared with nonsmoking males, and this seemed reversible for males who stop smoking. This study suggests a normal gradual vocal aging process with clear consequences in daily life, which should be taken into consideration in clinical practice as well as in studies concerning communication in social life.     

Laryngeal airway resistance in teacherswith vocal fatigue: A preliminary study

A noninvasive pressure-flow technique was used to compare laryngealairway resistances in nine female classroom teachers with symptoms of vocal fatigue and seven teachers without symptoms of vocal fatigue. Data were collected two times per day on the Monday, Wednesday, and Friday of a typical work-week. No significant between-group differences were found, but two within-group differences were notable. Airflow in the fatigued subjects decreased across the sampling period (p = .0009). In the controls, air pressure increased across the sampling period (p = .021). These findings suggest that both groups may have reacted to vocal demands during the week by employing two different strategies to maintain habitual laryngeal airway resistance: laryngeal adjustments alone or laryngeal adjustments plus increased respiratory drive. The first strategy, employed by the fatigued subjects, may have been less efficient, thereby provoking conditions associated with their vocal fatigue.     

The processing and perception of size information in speech sounds

There is information in speech sounds about the length of the vocal tract; specifically, as a child grows, the resonators in the vocal tract grow and the formant frequencies of the vowels decrease. It has been hypothesized that the auditory system applies a scale transform to all sounds to segregate size information from resonator shape information, and thereby enhance both size perception and speech recognition [Irino and Patterson, Speech Commun. 36, 181-203 (2002)]. This paper describes size discrimination experiments and vowel recognition experiments designed to provide evidence for an auditory scaling mechanism. Vowels were scaled to represent people with vocal tracts much longer and shorter than normal, and with pitches much higher and lower than normal. The results of the discrimination experiments show that listeners can make fine judgments about the relative size of speakers, and they can do so for vowels scaled well beyond the normal range. Similarly, the recognition experiments show good performance for vowels in the normal range, and for vowels scaled well beyond the normal range of experience. Together, the experiments support the hypothesis that the auditory system automatically normalizes for the size information in communication sounds.     

The Voice and Its Care: Survey Findings From Actors'' Perspectives

There is a need for research that would determine how the speech-language-voice pathologist could best be of service to actors who are experiencing vocal dysfunction or in furnishing preventive educational information. A questionnaire investigating interest and knowledge levels of vocal function and dysfunction was distributed to 543 subjects from the Pacific Northwest and British Columbia. A total of 345 questionnaires, including those completed by 79 professional actors, 73 amateur actors, 124 acting students, and 69 controls, were analyzed. Professional actors and amateur actors indicated the highest levels of interest in gaining further knowledge regarding the role of the speech-language pathologist (SLP) and the voice and vocal hygiene. Professional actors and amateur actors also reported higher perceived knowledge levels than the other groups in these areas, although very few claimed to have a thorough knowledge in the areas under investigation. Professional actors answered more knowledge-based questions correctly than amateur actors, acting students, and controls in the areas regarding the role of the SLP and voice and vocal hygiene. However, the professional actors' scores were not significantly higher than amateur actors in either area and were only significantly higher than acting students on the vocal hygiene items. Implications for a preventive approach to vocal health are discussed.     

Self-reported voice problems among three groups of professional singers

A vocal health questionnaire was administered to three groups of professional singers and a “friendship-matched” group of nonsingers in Melbourne, Australia. The responses of 79 opera, 57 musical theatre and 31 contemporary (excluding rock) singers and 86 nonsingers were analysed. The questionnaire solicited information regarding biographical data speaking and singing voice-use behaviours, and vocal health over the previous 12 months in terms of experiences of vocal impairment, vocal disability, and handicap. Significant differences between singers and nonsingers in the prevalence and nature of voice problems were reported. Of the singers, 44% reported one or more occurrences of a diagnosed vocal condition compared to 21% of nonsingers and 69% of singers experienced vocal disability compared to only 41% of nonsingers, over the previous 12 months. In contrast, no significant differences were found between the three different styles of singers in their experience of vocal impairment, disability or handicap.     

Fibronectin: An Interesting Vocal Fold Protein

A great deal of information is accruing regarding the function of the extracellular matrix. Once thought to be simply a structural entity to surround cells, it is now known to do much more. Fibronectin in particular has received specific attention. Fibronectin is a ubiquitous glycoprotein found most abundantly in the extracellular matrix of regenerating, healing, and embryonic tissue. Vast evidence supports the fact that fibronectin participates in many diverse functions throughout the body that are relevant to vocal fold biology. This article introduces the structure of fibronectin and its isoforms and provides an introduction to some of the many functions it plays. It also reviews the evidence about fibronectin's place in vocal folds and vocal fold pathology. It discusses fibronectin's presence in vocal nodules, vocal polyps, vocal scarring, and Reinke's edema, and reviews the data on its role in mucosal wave impairment. Lastly, it discusses preliminary microarray data that show gene expression for fibronectin to be upregulated in true vocal folds when compared to false vocal folds.     

Analysis of Vocal-fold Vibrations from High-Speed Laryngeal Images Using a Hilbert Transform-Based Methodology

This paper presents a Hilbert transform-based approach to analyze vocal fold vibrations in human subjects exhibiting normal and abnormal voice productions. This new approach is applied to the analysis of glottal area waveform (GAW) and is capable of providing useful information on the vocal fold vibration. The GAW is extracted from high-speed laryngeal images by delineating the glottal edge for each image frame. An analytic signal is generated through the Hilbert transform of the GAW, which yields a recognizable pattern of the vocal fold vibration in the analytic phase plane. The vibratory pattern is comprehensive and can be correlated with specific voice conditions. Quantitative measures of the glottal perturbation are introduced using the analytic amplitude and instantaneous frequency obtained from the analysis. Examples of clinical voice recordings are used to evaluate and test the effectiveness of this approach in providing qualitative representation and quantitative characteristics of vocal fold vibratory behavior. The results demonstrate the potential of using this new analytical tool incorporated with the high-speed laryngeal imaging modality for clinical voice assessment.     

Coaching Strategies for Behavioral Voice Therapy and Training

Coaching is one of the most common words in our modern vocabulary and has many meanings depending on the setting in which it is used. Coaching facilitates positive changes to achieve a goal, usually through indirect approaches, including improving an individual's outlook on their behaviors or attitudes. Its application has spread beyond the corporate world, and many medical specialties use coaching principles. The goals of this article are to introduce coaching as a profession, and to explore the function of a vocal coach to improve communicative and vocal performance. Moreover, differences between voice therapy and voice training are highlighted, including the principles subjacent to these interventions and the use of coaching strategies. Four strategies of professional coach practitioners adapted to the training and therapy of the voice with applications to both are described. These are: powerful questions, active listening, changing habits, and implementation intention. The use of these strategies may help individuals to achieve high voice performance. Most importantly, the speech-language pathologist voice specialist can apply these strategies particularly in cases of behavioral dysphonias, which can be resistant to traditional voice therapy.     

Cochlear Implant Users’ Vocal Control CorrelatesAcross Tasks

Cochlear implants (CIs) provide access to auditory information that can affect vocal control. For example, previous research shows that, when producing a sustained vowel, CI users will alter the pitch of their voice when the feedback of their own voice is perceived to shift. Although these results can be informative as to how perception and production are linked for CI users, the artificial nature of the task raises questions as to the applicability of the results to real-world vocal productions. To examine how vocal control, when producing sustained vowels, relates to vocal control for more ecologically valid tasks, 10 CI users’ vocal control was measured across two tasks: (1) sustained vowel production, and (2) singing. The results found that vocal control, as measured by the variability of the participants’ fundamental frequency, was significantly correlated when producing sustained vowels and when singing, although variability was significantly greater when singing. This suggests that, despite the artificial nature of sustained vowel production, vocal control on such tasks is related to vocal control for more ecologically valid tasks. However, the results also suggest that vocal control may be overestimated with sustained vowel production tasks.