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Purpose: The purpose of this study is to identify the extent to which various measurements of contacting parameters differ between children and adults during habitual range and overlap vocal frequency/intensity, using voice map-based assessment of noninvasive electroglottography (EGG). Method: EGG voice maps were analyzed from 26 adults (22-45 years) and 22 children (4-8 years) during connected speech and vowel /a/ over the habitual range and the overlap vocal frequency/intensity from the voice range profile task on the vowel /a/. Mean and standard deviations of contact quotient by integration, normalized contacting speed, quotient of speed by integration, and cycle-rate sample entropy were obtained. Group differences were evaluated using the linear mixed model analysis for the habitual range connected speech and the vowel, whereas analysis of covariance was conducted for the overlap vocal frequency/intensity from the voice range profile task. Presence of a 'knee' on the EGG wave shape was determined by visual inspection of the presence of convexity along the decontacting slope of the EGG pulse and the presence of the second derivative zero-crossing. Results: The contact quotient by integration, normalized contacting speed, quotient of speed by integration, and cycle-rate sample entropy were significantly different in children compared to (a) adult males for habitual range and (b) adult males and adult females for the overlap vocal frequency/intensity. None of the children had a 'knee' on the decontacting slope of the EGG slope. Conclusion: EGG parameters of contact quotient by integration, normalized contacting speed, quotient of speed by integration, cycle-rate sample entropy, and absence of a 'knee' on the decontacting slope characterize the wave shape differences between children and adults, whereas the normalized contacting speed, quotient of speed by integration, cycle-rate sample entropy, and presence of a 'knee' on the downward pulse slope characterize the wave shape differences between adult males and adult females. Supplemental Material: https://doi.org/10.23641/asha. 15057345, Dysphonia affects one third of the population at some point in their life (Cohen et al., 2012) and can affect all ages. Among school-age children, the prevalence of dysphonia ranges [...]

Purpose: To determine if respiratory and laryngeal function during spontaneous speaking were different for teachers with voice disorders compared with teachers without voice problems. Method: Eighteen teachers, 9 with and 9 without voice disorders, were included in this study. Respiratory function was measured with magnetometry, and laryngeal function was measured with electroglottography during 3 spontaneous speaking tasks: a simulated teaching task at a typical loudness level, a simulated teaching task at an increased loudness level, and a conversational speaking task. Electroglottography measures were also obtained for 3 structured speaking tasks: a paragraph reading task, a sustained vowel, and a maximum phonation time vowel. Results: Teachers with voice disorders started and ended their breath groups at significantly smaller lung volumes than teachers without voice problems during teaching-related speaking tasks; however, there were no between-group differences in laryngeal measures. Task-related differences were found on several respiratory measures and on one laryngeal measure. Conclusions: These findings suggest that teachers with voice disorders used different speech breathing strategies than teachers without voice problems. Implications for clinical management of teachers with voice disorders are discussed.

Purpose: Approximately 30% of adults over the age of 50 years present with altered vocal function. Our understanding of how these changes manifest acoustically and perceptually is derived from relatively modest-sized studies using a diversity of tools. Voice changes can arise from the onset of disease or disorder, but also age-related physiological changes, which may not reflect pathology as such. Here, we bring together data on acoustic, perceptual, and instrumental assessments (electroglottography), with the aim of gaining a better understanding of the changes occurring across these measurement domains. We consider these changes in the context of different acoustic features, software programs, and perceptual protocols. Method: Studies of voice function in healthy older adults over the age of 50 years were sought. Literature was systematically searched with 746 abstracts reviewed. Forty-seven studies were included in the review. A meta-analysis of included studies compared voice acoustic parameters between sex and age. Sixteen acoustic parameters collected from 1,475 participants were analyzed in the meta-analysis. These included some previously unpublished analyses using data provided by authors of included studies. Results: Data from the systematic review suggest that older individuals are perceived to present with higher overall scores of dysphonia and roughness, breathiness, strain, and instability. Acoustically, males have significantly higher scores on measures of perturbation, including noise-to-harmonic ratio and absolute jitter. The meta-analysis outcomes suggest that participants aged 80-89 years produce significantly higher fundamental frequency, jitter percent, shimmer percent, and shimmer in decibels compared to participants aged 60-69 years and a significant increase in relative average perturbation, jitter percent, and shimmer in decibels compared to participants aged 70-79 years. Limited data were available comparing acoustic measures using the same acoustic software. Conclusions: Variations in fundamental frequency and frequency and amplitude perturbation increase as healthy adults age. It was difficult to draw definitive conclusions based on existing literature due to variability in hardware used, limited descriptions of study cohorts, or missing data from statistical analysis. Supplemental Material: https://doi.org/10.23641/asha. 11868663, A proportion of healthy older adults present with differences in voice compared to their younger age equivalents. These voice changes can arise from the onset of disease or disorder, but [...]

Purpose: To advance our current knowledge of singer physiology by using ultrasonography in combination with acoustic measures to compare physiological differences between musical theater (MT) and opera (OP) singers under controlled phonation conditions. Primary objectives addressed in this study were (a) to determine if differences in hyolaryngeal and vocal fold contact dynamics occur between two professional voice populations (MT and OP) during singing tasks and (b) to determine if differences occur between MT and OP singers in oral configuration and associated acoustic resonance during singing tasks. Method: Twenty-one singers (10 MT and 11 OP) were included. All participants were currently enrolled in a music program. Experimental procedures consisted of sustained phonation on the vowels /i/ and /a/ during both a low-pitch task and a high-pitch task. Measures of hyolaryngeal elevation, tongue height, and tongue advancement were assessed using ultrasonography. Vocal fold contact dynamics were measured using electroglottography. Simultaneous acoustic recordings were obtained during all ultrasonography procedures for analysis of the first two formant frequencies. Results: Significant oral configuration differences, reflected by measures of tongue height and tongue advancement, were seen between groups. Measures of acoustic resonance also showed significant differences between groups during specific tasks. Both singer groups significantly raised their hyoid position when singing high-pitched vowels, but hyoid elevation was not statistically different between groups. Likewise, vocal fold contact dynamics did not significantly differentiate the two singer groups. Conclusions: These findings suggest that, under controlled phonation conditions, MT singers alter their oral configuration and achieve differing resultant formants as compared with OP singers. Because singers are at a high risk of developing a voice disorder, understanding how these two groups of singers adjust their vocal tract configuration during their specific singing genre may help to identify risky vocal behavior and provide a basis for prevention of voice disorders., A professional voice user can be defined as anyone whose employment or livelihood depends on the use or quality of his or her voice (Colton et al., 2011; Titze et [...]

Purpose: The purpose of this study was to investigate the characteristics of diplophonia using an auditory perception and multimodal simultaneous examination, which included sound waveform analysis, electroglottography (EGG), digital kymography (DKG), and 2-dimensional scanning digital kymography (2D DKG). Additionally, we compared the diagnostic accuracy of each method using a binary classifier in confusion matrix and convenience of discrimination, based on the time required for interpretation. Method: One normophonic male, 12 patients with diplophonia, and 12 dysphonia patients without diplophonia were enrolled. A multimodal simultaneous evaluation was used to analyze the vibration pattern of diplophonia. Sensitivity, specificity, accuracy, area under the curve, and interpretation time were used to compare the various diagnostic methods. Discrimination was determined by 3 raters. Results: There are 3 types of asymmetric vibratory patterns in diplophonia. The types are based on the oscillators vibrating at different frequencies: asymmetry of the left and right cords (6 subjects with unilateral palsy and 1 subject with vocal polyps), asymmetry of anterior and posterior cords (2 subjects with vocal polyps), and asymmetry of true and false cords (3 subjects with muscle tension dysphonia). All evaluation methods were useful as diagnostic tools, with all areas under the curve > .70. The diagnostic accuracy was highest with DKG (95.83%), followed by 2D DKG (83.33%), EGG (81.94%), auditory-perceptual evaluation (80.56%), and sound waveform (77.78%). The interpretation time was the shortest for auditory-perceptual evaluation (6.07 [+ or -] 1.34 s), followed by 2D DKG (10.04 [+ or -] 3.00 s), EGG (12.49 [+ or -] 2.76 s), and DKG (13.53 [+ or -] 2.60 s). Conclusions: Auditory-perceptual judgment was the easiest and fastest method for experienced raters, but its diagnostic accuracy was lower than that of DKG or 2D DKG. The diagnostic accuracy of DKG was the highest, but 2D DKG allowed rapid interpretation and showed relatively high diagnostic accuracy, except in cases with space-occupying lesions. Supplemental Material: https://doi.org/10.23641/asha. 9911786, Diplophonia should be considered as a voice phenomenon, rather than a voice disorder. It most commonly occurs in subjects with unilateral vocal cord paralysis and can also be observed in [...]

Purpose: Resonance tube phonation in water (RTPW) or in air is a voice therapy method successfully used for treatment of several voice pathologies. Its effect on the voice has not been thoroughly studied. This investigation analyzes the effects of RTPW on collision and phonation threshold pressures (CTP and PTP), the lowest subglottal pressure needed for vocal fold collision and phonation, respectively. Method: Twelve mezzo-sopranos phonated into a glass tube, the end of which was placed under the water surface in a jar. Subglottal pressure, electroglottography, and audio signals were recorded before and after exercise. Also, the perceptual effects were assessed in a listening test with an expert panel, who also rated the subjects' singing experience. Results: Resonance tube phonation significantly increased CTP and also tended to improve perceived voice quality. The latter effect was mostly greater in singers who did not practice singing daily. In addition, a more pronounced perceptual effect was found in singers rated as being less experienced. Conclusion: Resonance tube phonation significantly raised CTP and tended to improve perceptual ratings of voice quality. The effect on PTP did not reach significance. Key Words: collision threshold pressure, phonation threshold pressure, semi-occluded vocal tract, EGG, voice therapy, voice training, Resonance tube phonation is a voice therapy method that was first introduced by Antti Sovijarvi (1965, 1969; as cited by Simberg & Laine, 2007). It is now commonly used in [...]

Jitter, or the amount of cycle-to-cycle variation in the fundamental frequency, is a characteristic of the vocal folds' vibration that may affect electroglottographic (EGG) and acoustic signals in similar ways, because the translaryngeal conductance and the oral pressure are modulated by the some physiological mechanism. Despite the apparent simplicity in jitter computation and the relative facility in recording and analyzing EGG signals, only a few studies comparing EGG and acoustic jitter have been reported. This can be attributed to the remarkable sensitivity of measures of acoustic jitter to such features as the type of sound being analyzed, the equipment used for data acquisition, or the algorithms used to identify glottal cycle boundaries. To assess the agreement achievable by measures from these signals in pathological voices, acoustic and EGG waveforms of sustained vowels (/i/, /a/, /u/) produced by 15 dysphonic patients were analyzed by jitter extraction methods on the basis of peaks, zero crossings, and a waveform matching technique. The agreement, expressed as normalized absolute differences between acoustic- and EGG-derived jitter, was poorer for /i/ and /u/ than for /a/ vowels. For /a/ vowels, a method of acoustic jitter estimation is also proposed that combines peaks and zero crossings and resulted in increased consistency with the zero crossing-based EGG measures (mean normalized absolute difference: 10.95%; SD: 6.44%; range: 23.81%). The proposed method, which has a built-in test intended to reject unreliable estimates, may provide more confidence in acoustic measures in dysphonic speakers and lead to a better understanding of the relationships between acoustic and EGG signals. KEY WORDS: jitter, voice, electroglottography, acoustic, dysphonia

Purpose: Laryngeal high-speed videoendoscopy (LHSV) has been recognized as a highly valuable modality for the scientific investigations of vocal fold (VF) vibrations. In contrast to stroboscopic imaging, LHSV enables visualizing aperiodic VF vibrations. However, the technique is less well established in the clinical care of disordered voices, partly because the properties of aperiodic vibration patterns are not yet described comprehensively. To address this, a computer model for simulation of VF vibration patterns observed in a variety of different phonation types is proposed. Method: A previously published kinematic model of mucosal wave phenomena is generalized to be capable of left-right asymmetry and to simulate endoscopic videos instead of only kymograms of VF vibrations at single sagittal positions. The most influential control parameters are the glottal halfwidths, the oscillation frequencies, the amplitudes, and the phase delays. Results: The presented videos demonstrate zipper-like vibration, pressed voice, voice onset, constant and time-varying left-right and anterior-posterior phase differences, as well as left-right frequency differences of the VF vibration. Video frames, videokymograms, phonovibrograms, glottal area waveforms, and waveforms of VF contact area relating to electroglottograms are shown, as well as selected kinematic parameters. Conclusion: The presented videos demonstrate the ability to produce vibration patterns that are similar to those typically seen in endoscopic videos obtained from vocally healthy and dysphonic speakers. Supplemental Material: https://doi.org/10.23641/asha.20151833, Vocal fold (VF) geometry and kinematics reflect vocal health status, and they serve as key elements in relating voice physiology to voice acoustics and perception. In contrast to self-oscillating models, [...]

Purpose: Despite the high prevalence of primary muscle tension dysphonia (MTD-1), its underlying mechanisms and their interrelationships have yet to be fully identified. The objectives of this integrative review were (a) to describe and classify the suggested underlying mechanisms for MTD-1, (b) to appraise the empirical evidence supporting each of the proposed mechanisms, and (c) to summarize the information in an integrative model. Method: PubMed, Scopus, and CINAHL were searched for all publications pertaining to muscle tension dysphonia. Papers were retained if they included theoretical or empirical data pertaining to underlying mechanisms of MTD-1. A total of 921 papers initially qualified for screening, of which 100 remained for consideration in this review. Underlying mechanisms of MTD-1 were extracted using a consensus approach. Results: Seven broad categories of putative mechanisms involved in MTD-1 were identified: psychosocial, autonomic, sensorimotor, respiratory, postural, inflammatory, and neuromuscular. These categories were further divided into 19 subcategories detailed in the body of this review article. Based on the reviewed evidence, our proposed integrative model presents MTD-1 as an idiosyncratic motor adaptation to physiological perturbation or perceived threat. Under this model, physiologically or psychologically aversive stimuli can instigate a series of motor adaptations at multiple levels of the nervous system, ultimately disturbing muscle activation patterns and their biomechanical outcomes. Importantly, these adaptations appear to have the potential to become chronic even after threatening stimuli are withdrawn. Conclusions: The proposed model highlights the importance of personalized rehabilitation in MTD-1 treatment. Limitations of the literature are discussed to provide guidance for future research aimed at improving our understanding of MTD-1. Supplemental Material: https://doi.org/10.23641/asha.19586065, The Classification Manual of Voice Disorders defines primary muscle tension dysphonia (MTD-1) as a 'dysphonia in the absence of current organic vocal fold pathology, without obvious psychogenic or neurologic etiology, [...]

Purpose: This study primarily aimed at observing the possible tissue mobilization on facial, neck, and chest tissues caused by different double source of vibration semioccluded vocal tract exercises (DSV-SOVTEs). Another goal was to inspect the degree of self-perceived sensation of a massage-like sensation. Method: Fifty-five participants engaged in a set of several DSV-SOVTEs: (a) phonation with a silicone tube submerged 2 and 8 cm below water surface, (b) Acapella Choice device, (c) lip trills, and (d) tongue trills. A self-perceived massage-like sensation was also assessed. All exercises were performed at three loudness levels. Tissue mobilization signal was captured by four accelerometers placed in four different body regions: (a) over the cheek, (b) over the neck, (c) over the thyroid cartilage, and (d) over the suprasternal notch. Results: There is a differential effect of all DSV-SOVTEs on tissue mobilization. All four observed dependent variables from tissue oscillation modulation (frequency, amplitude, jitter, and shimmer) showed significant three-way interactions. In general, amplitude and frequency of tissue oscillation modulation increases with loudness. A self-perceived massage-like sensation showed highly significant differences between DSV-SOVTEs. Conclusions: All DSV-SOVTEs do mobilize tissues. Type of exercise, loudness level, and body region produce an effect on all tissue oscillation variables. Acapella device produces the largest amplitude of vibration, lowest frequency, and more regular oscillation of tissue. Water resistance therapy showed the most irregular tissue oscillation. Control of these variables is likely to be relevant to obtain the best outcomes in patients., Depending on the number of sources of vibration involved, semioccluded vocal tract exercises (SOVTEs) can be grouped into two different categories: (a) steady exercises with a single source of vibration [...]

Purpose: This study aims to investigate the effects of a 10-min vocal exertion task on voice and respiratory measures, to determine whether restorative strategies can mitigate these effects after cessation of exertion, and to assess whether these strategies continue to reduce these detrimental effects when vocal exertion is resumed. Method: A prospective, repeated-measures design was used. On consecutive days, 20 participants (equal men and women) completed two vocal exertion tasks separated by 10 min of restoration strategies: vocal rest or controlled phonation (low-level tissue mobilization using straw phonation). Voice and respiratory data were collected at baseline, following the first exertion task, after restoration strategies, and after the second exertion task. Outcome measures included (a) vocal effort, (b) phonation threshold pressure, (c) maximum and minimum fundamental frequencies, (d) cepstral peak prominence of connected speech, (e) lung volume initiation and termination, (f) percent vital capacity expended per syllable, and (g) number of syllables per breath group. Results: A worsening of phonation threshold pressure (p < .001), vocal effort (p < .001), and increase of minimum fundamental frequency (p = .007) were observed after vocal exertion. Lung volume initiation (p < .001) and lung volume termination (p < .001) increased. These changes were largely reversed by restoration strategies, but only controlled phonation prevented exertion-induced changes in respiratory kinematic measures on a subsequent vocal exertion task. Conclusions: Exertion-induced voice changes occur rapidly and may be mitigated by either controlled phonation or vocal rest. Controlled phonation is recommended as a superior strategy due to evidence of a protective effect on a successive vocal exertion task., Situations requiring vocal exertion are common in occupational and social-cultural contexts. For example, careers in fields such as education, the performing arts, and public safety require continuous phonation, often at [...]

Purpose: Dysphonia can be evaluated by both patientreported quality of life instruments and objective acoustic and aerodynamic analyses. However, less is known about the association between the two metrics. The goal of this study was to perform a meta-analysis of the correlation of the Voice Handicap Index (VHI-30) with the following objective parameters: fundamental frequency, jitter, shimmer, harmonics to noise ratio, noise to harmonic ratio, maximum phonation time, and the Dysphonia Severity Index. Method: A literature search was performed in the PubMed, Scopus, and Cumulative Index of Nursing and Allied Health Literature databases. Inclusion criteria were subjects age 18 years and older with voice complaints and assessed by both VHI-30 and objective voice analysis. Results: A literature search resulted in 1,297 unique articles, of which 310 underwent full-text review and 17 studies were included in quantitative analysis. Significant pooled correlation was observed for VHI-30 total with jitter (.301 [.177; .416]), shimmer (.255 [.162; .344]), noise to harmonic ratio (.200 [.111; .285]), maximum phonation time (-.227 [-.352; -.094]), and Dysphonia Severity Index (-.254[-.455; -.0286]). Significant correlations were observed in 4/7 objective parameters with the Physical subscale, 3/7 with the Functional subscale, and 2/7 with the Emotional subscale. All significant correlations were negligible (0-.3) or low (.3-.5). Conclusions: Results from meta-analysis showed that correlations between objective voice parameters and the VHI-30 were negligible or low. Further study is needed to determine if correlations vary by patient demographics or specific pathology., Dysphonia, impairment of the voice, affects many individuals in the United States and creates millions of dollars in direct health care costs every year (Benninger et al., 2017). There is [...]

Purpose: Laboratory stressors have been shown to impact the activity of the intrinsic laryngeal muscles (ILMs), which may be part of the final causal pathway in some stressinduced voice disorders. Previous research suggests that personality traits such as stress reaction might increase one's susceptibility to these problems. Also, the autonomic nervous system response is implicated in the pathogenesis of voice disorders putatively involving ILM hyperfunction. The purpose of this study was to investigate personality and autonomic nervous system predictors of ILM responses to stressor exposure. Method: Thirty-seven physically and vocally healthy female adults completed a personality questionnaire and were subjected to a speech preparation task intended to induce stress. Fine wire electromyography of the ILMs was performed so that the activity of these muscles could be measured prior to and during the stressor. Participants' trait stress reaction was measured as a personality-based predictive variable, as was respiratory-corrected respiratory sinus arrhythmia, a putative measure of vagal outflow to the heart. Results: The personality measure trait stress reaction uniquely predicted thyroarytenoid, trapezius, and tibialis activity, whereas respiratory sinus arrhythmia uniquely predicted the activity of all muscles studied. Differences were observed in the autonomic predictor variable as a function of whether or not effects of respiration were accounted for in the variable's calculation. Conclusions: This study explores the potential mediating roles of personality and autonomic function in ILM activity during a stressor. Both variables have value in predicting ILM activity during stressor exposure., We previously examined the claim that the intrinsic laryngeal muscles (ILMs) respond to physical and psychosocial stressors with increased activation and characterized the nature of the ILM stress response (Helou [...]

Purpose: Sarcasm is a specialized speech act in daily vocal communication usually characterized by unique prosodic features, but the role of voice quality in expressing sarcasm has not been explored much. The goal of this study is to explore the voice quality features of Mandarin sarcastic speech in comparison to sincere speech. Method: Fifteen male and 15 female native speakers of Mandarin uttered 31 target sentences with both sincere and sarcastic attitudes. Nine voice quality parameters extracted from the acoustic and electroglottographic signals were analyzed using a linear mixed model, and a classification analysis using a random forest algorithm was conducted to identify the relative contribution of these parameters to the differentiation between sincere and sarcastic utterances. Results: In comparison to sincere speech, sarcastic speech had a creakier voice, which was characterized by a lower fundamental frequency, a greater degree of vocal fold adduction (i.e., higher contact quotient), lesser noise (i.e., higher harmonics-to-noise ratio), and more multiple pulsing (i.e., higher subharmonic-to-harmonic ratio). The interaction effect revealed a gender difference in the use of creakier voice to express sarcasm in Mandarin. The classification analysis using the random forest algorithm showed that the nine voice quality parameters resulted in 84.0% and 83.7% identification rates for sarcastic and sincere utterances, respectively. Conclusions: The results of this preliminary study support the role of voice quality in expressing sarcasm in Mandarin speech. Using a set of voice quality parameters, sarcastic and sincere utterances can be effectively identified. Furthermore, there is a gender difference in the use of creakier voice in expressing Mandarin sarcastic speech. Supplemental Material: https://doi.org/10.23641/asha. 12743780, In speech communication, speech signals convey not only linguistic information but also paralinguistic/ nonlinguistic information (Fujisaki, 2004). While the nature of how speech signals convey linguistic information has been well [...]

Purpose: Given the established linear relationship between neck surface vibration magnitude and mean subglottal pressure (Ps) in vocally healthy speakers, the purpose of this study was to better understand the impact of the presence of a voice disorder on this baseline relationship. Method: Data were obtained from participants with voice disorders representing a variety of glottal conditions, including phonotraumatic vocal hyperfunction, nonphonotraumatic vocal hyperfunction, and unilateral vocal fold paralysis. Participants were asked to repeat /p/-vowel syllable strings from loud-to-soft loudness levels in multiple vowel contexts (/pa/, /pi/, /pu/) and pitch levels (comfortable, higher than comfortable, lower than comfortable). Three statistical metrics were computed to analyze the regression line between neck surface accelerometer (ACC) signal magnitude and Ps within and across pitch, vowel, and voice disorder category: coefficient of determination ([r.sup.2]), slope, and intercept. Three linear mixed-effects models were used to evaluate the impact of voice disorder category, pitch level, and vowel context on the relationship between ACC signal magnitude and Ps. Results: The relationship between ACC signal magnitude and Ps was statistically different in patients with voice disorders than in vocally healthy controls; patients exhibited higher levels of Ps given similar values of ACC signal magnitude. Negligible effects were found for pitch condition within each voice disorder category, and negligible-to-small effects were found for vowel context. The mean of patient-specific [r.sup.2] values was .63, ranging from .13 to .92. Conclusions: The baseline, linear relationship between ACC signal magnitude and Ps is affected by the presence of a voice disorder, with the relationship being participant-specific. Further work is needed to improve ACC-based prediction of Ps, across treatment, and during naturalistic speech production., Subglottal pressure (Ps) plays a major role in voice production and is a primary factor in controlling voice onset, offset, and intensity and contributes to variation in fundamental frequency f0). [...]

Purpose: Oral air pressure measurements during lip occlusion for /pVpV/ syllable strings are used to estimate subglottal pressure during the vowel. Accuracy of this method relies on smoothly produced syllable repetitions. The purpose of this study was to investigate the oral air pressure waveform during the /p/ lip occlusions and propose physiological explanations for nonflat shapes. Method: Ten adult participants were trained to produce the 'standard condition' and were instructed to produce nonstandard tasks. Results from 8 participants are included. The standard condition required participants to produce /p:i:p:i:.../ syllables smoothly at approximately 1.5 syllables/s. The nonstandard tasks included an air leak between the lips, faster syllable repetition rates, an initial voiced consonant, and 2-syllable word productions. Results: Eleven oral air pressure waveform shapes were identified during the lip occlusions, and plausible physiological explanations for each shape are provided based on the tasks in which they occurred. Training the use of the standard condition, the initial voice consonant condition, and the 2-syllable word production increased the likelihood of rectangular oral air pressure waveform shapes. Increasing the rate beyond 1.5 syllables/s improved the probability of producing rectangular oral air pressure signal shapes in some participants. Conclusions: Visual and verbal feedback improved the likelihood of producing rectangular oral air pressure signal shapes. The physiological explanations of variations in the oral air pressure waveform shape may provide direction to the clinician or researcher when providing feedback to increase the accuracy of estimating subglottal pressure from oral air pressure., Subglottal pressure provides the aerodynamic driving force in phonation. Average subglottal or tracheal pressure tends to increase for patients with nodules, polyps, laryngeal cancer, or hyperadductive behaviors (Giovanni, Demolin, Heim, [...]

Purpose: This study evaluated how 1st and 2nd vowel formant frequencies (F1, F2) differ between normal and loud speech in multiple speaking tasks to assess claims that loudness leads to exaggerated vowel articulation. Method: Eleven healthy German-speaking women produced normal and loud speech in 3 tasks that varied in the degree of spontaneity: reading sentences that contained isolated /i: a: u:/, responding to questions that included target words with controlled consonantal contexts but varying vowel qualities, and a recipe recall task. Loudness variation was elicited naturalistically by changing interlocutor distance. First and 2nd formant frequencies and average sound pressure level were obtained from the stressed vowels in the target words, and vowel space area was calculated from /i: a: u:/. Results: Comparisons across many vowels indicated that high, tense vowels showed limited formant variation as a function of loudness. Analysis of /i: a: u:/ across speech tasks revealed vowel space reduction in the recipe retell task compared to the other 2. Loudness changes for F1 were consistent in direction but variable in extent, with few significant results for high tense vowels. Results for F2 were quite varied and frequently not significant. Speakers differed in how loudness and task affected formant values. Finally, correlations between sound pressure level and F1 were generally positive but varied in magnitude across vowels, with the high tense vowels showing very flat slopes. Discussion: These data indicate that naturalistically elicited loud speech in typical speakers does not always lead to changes in vowel formant frequencies and call into question the notion that increasing loudness is necessarily an automatic method of expanding the vowel space. Supplemental Material: https://doi.org/10.23641/asha. 8061740, Loudness modulation is a natural part of typical speech production, and targeting loud speech is also used in clinical intervention for persons with motor speech disorders. Elucidating the ways in [...]

Purpose: Singers are vocal athletes having specific demands from their voice and require special consideration during voice evaluation. Presently, there is a lack of standards for acoustic evaluation in them. The aim of the present study was to systematically review the available literature on the acoustic analysis of voice in singers. Method: A systematic review of studies on acoustic analysis of voice in singers (PubMed/MEDLINE, CINAHL, Scopus, ProQuest, Cochrane, Ovid, Science Direct, and Shodhganga) was carried out. Key words based on PIO (population-investigation-outcome) were used to develop search strings. Titles and abstracts were screened independently, and appropriate studies were read in full for data extraction. Results: Of the 895 studies, 26 studies met the inclusion criteria. Great variability was noted in the instruments and task used. Different acoustic measures were employed, such as fundamental frequency, perturbation, cepstral, spectral, dysphonia severity index, singing power ratio, and so forth. Conclusion: Overall, a great heterogeneity was noted regarding population, tasks, instruments, and parameters. There is a lack of standardized criteria for the evaluation of singing voice. In order to implement acoustic analysis as a part of comprehensive voice evaluation exclusively for singers, there is a certain need for methodical sound studies., The human voice is the result of interaction between the respiratory, laryngeal, and resonatory systems. This multidimensional nature of voice requires it to be evaluated using diverse domains, such as [...]

Purpose: This study investigated acoustic-phonetic modifications produced in noise-adapted speech (NAS) and clear speech (CS) by children, young adults, and older adults. Method: Ten children (11-13 years of age), 10 young adults (18-29 years of age), and 10 older adults (60-84 years of age) read sentences in conversational and clear speaking style in quiet and in noise. A number of acoustic measurements were obtained. Results: NAS and CS were characterized by a decrease in speaking rate and an increase in 1-3 kHz energy, sound pressure level (SPL), vowel space area (VSA), and harmonics-to-noise ratio. NAS increased fundamental frequency (F0) mean and decreased jitter and shimmer. CS increased frequency and duration of pauses. Older adults produced the slowest speaking rate, longest pauses, and smallest increase in F0 mean, 1-3 kHz energy, and SPL when speaking clearly. They produced the smallest increases in VSA in NAS and CS. Children slowed down less, increased the VSA least, increased harmonics-to-noise ratio, and decreased jitter and shimmer most in CS. Children increased mean F0 and F1 most in noise. Conclusions: Findings have implications for a model of speech production in healthy speakers as well as the potential to aid in clinical decision making for individuals with speech disorders, particularly dysarthria., This study is the first of two articles examining speaking style adaptations that children, young adults, and older adults implement when speaking in response to noise (noise-adapted speech, NAS) and [...]

Purpose: The aim of the present study was to qualitatively and quantitatively characterize vocal fold vibrations in sulcus vocalis by high-speed digital imaging (HSDI) and to clarify the correlations between HSDI-derived parameters and traditional vocal parameters. Method: HSDI was performed in 20 vocally healthy subjects (8 men and 12 women) and 41 patients with sulcus vocalis (33 men and 8 women). Then HSDI data were evaluated by assessing the visual-perceptual rating, digital kymography, and glottal area waveform. Results: Patients with sulcus vocalis frequently had spindle-shaped glottal gaps and a decreased mucosal wave. Compared with the control group, the sulcus vocalis group showed higher open quotient as well as a shorter duration of the visible mucosal wave, a smaller speed index, and a smaller glottal area difference index ([maximal glottal area minimal glottal area]/maximal glottal area). These parameters deteriorated in order of the control group and Type I, II, and III sulcus vocalis. There were no gender-related differences. Strong correlations were noted between the open quotient and the type of sulcus vocalis. Conclusions: HSDI was an effective method for documenting the characteristics of vocal fold vibrations in patients with sulcus vocalis and estimating the severity of dysphonia., Sulcus vocalis is a vocal disorder that results from a sulcus (indentation, groove, or furrow) at the edge of the vocal fold (Giovanni, Chanteret, & Lagier, 2007). The sulcus develops [...]

Purpose: This study investigated the acoustic characteristics of spontaneous speech by talkers aged 9-14 years and their ability to adapt these characteristics to maintain effective communication when intelligibility was artificially degraded for their interlocutor. Method: Recordings were made for 96 children (50 female participants, 46 male participants) engaged in a problem-solving task with a same-sex friend; recordings for 20 adults were used as reference. The task was carried out in good listening conditions (normal transmission) and in degraded transmission conditions. Articulation rate, median fundamental frequency (f0), f0 range, and relative energy in the 1- to 3-kHz range were analyzed. Results: With increasing age, children significantly reduced their median f0 and f0 range, became faster talkers, and reduced their mid-frequency energy in spontaneous speech. Children produced similar clear speech adaptations (in degraded transmission conditions) as adults, but only children aged 11-14 years increased their f0 range, an unhelpful strategy not transmitted via the vocoder. Changes made by children were consistent with a general increase in vocal effort. Conclusion: Further developments in speech production take place during later childhood. Children use clear speech strategies to benefit an interlocutor facing intelligibility problems but may not be able to attune these strategies to the same degree as adults., An important aspect of speech communication is the ability to adapt one's speech, at both the acoustic-phonetic and linguistic levels, to promote understanding in whatever situation in which communication is [...]

Purpose: The authors discuss the rationale behind the term laryngeal high-speed videoendoscopy to describe the application of high-speed endoscopic imaging techniques to the visualization of vocal fold vibration. Method: Commentary on the advantages of using accurate and consistent terminology in the field of voice research is provided. Specific justification is described for each component of the term high-speed videoendoscopy, which is compared and contrasted with alternative terminologies in the literature. Results: In addition to the ubiquitous high-speed descriptor, the term endoscopy is necessary to specify the appropriate imaging technology and distinguish among modalities such as ultrasound, magnetic resonance imaging, and nonendoscopic optical imaging. Furthermore, the term video critically indicates the electronic recording of a sequence of optical still images representing scenes in motion, in contrast to strobed images using high-speed photography and nonoptical high-speed magnetic resonance imaging. High-speed videoendoscopy thus concisely describes the technology and can be appended by the desired anatomical nomenclature such as laryngeal. Conclusions: Laryngeal high-speed videoendoscopy strikes a balance between conciseness and specificity when referring to the typical high-speed imaging method performed on human participants. Guidance for the creation of future terminology provides clarity and context for current and future experiments and the dissemination of results among researchers., The accurate and consistent use of terminology is an important trait for any scientific field. Describing technologies with concise and specific language helps to disambiguate nomenclature, provides a common reference [...]

Purpose: Schoolteachers have become a benchmark population for the study of occupational voice use. A decade of vibration-dose studies on the teacher population allows a comparison to be made between specific dose measures for eventual assessment of damage risk. Method: Vibration dosimetry is reformulated with the inclusion of collision stress. Two methods of estimating amplitude of vocal-fold vibration are compared to capture variations in vocal intensity. Energy loss from collision is added to the energy-dissipation dose. An equal-energy-dissipation criterion is defined and used on the teacher corpus as a potential-damage risk criterion. Results: Comparison of time-, cycle-, distance-, and energy-dose calculations for 57 teachers reveals a progression in information content in the ability to capture variations in duration, speaking pitch, and vocal intensity. The energy-dissipation dose carries the greatest promise in capturing excessive tissue stress and collision but also the greatest liability, due to uncertainty in parameters. Cycle dose is least correlated with the other doses. Conclusion: As a first guide to damage risk in excessive voice use, the equal-energy-dissipation dose criterion can be used to structure trade-off relations between loudness, adduction, and duration of speech., Prolonged speaking, shouting, or singing may expose the larynx to excessive tissue vibrations. It is well known that excessive hand vibration in industrial tool use can cause deleterious effects on [...]

Purpose: Although there is a long history of use of semi-occluded vocal tract gestures in voice therapy, including phonation through thin tubes or straws, the efficacy of phonation through tubes has not been established. This study compares results from a therapy program on the basis of phonation through a flow-resistant tube (FRT) with Vocal Function Exercises (VFE), an established set of exercises that utilize oral semi-occlusions. Method: Twenty subjects (16 women, 4 men) with dysphonia and/or vocal fatigue were randomly assigned to 1 of 4 treatment conditions: (a) immediate FRT therapy, (b) immediate VFE therapy, (c) delayed FRT therapy, or (d) delayed VFE therapy. Subjects receiving delayed therapy served as a no-treatment control group. Results: Voice Handicap Index (Jacobson et al., 1997) scores showed significant improvement for both treatment groups relative to the no-treatment group. Comparison of the effect sizes suggests FRT therapy is noninferior to VFE in terms of reduction in Voice Handicap Index scores. Significant reductions in Roughness on the Consensus Auditory-Perceptual Evaluation of Voice (Kempster, Gerratt, Verdolini Abbott, Barkmeier-Kraemer, & Hillman, 2009) were found for the FRT subjects, with no other significant voice quality findings. Conclusions: VFE and FRT therapy may improve voice quality of life in some individuals with dysphonia. FRT therapy was noninferior to VFE in improving voice quality of life in this study., Voice disorders affect the ability to communicate at work and in recreational activities. The lifetime prevalence of self-reported voice problems in adults has been found to be almost 30%, with [...]

Purpose: The purpose of the study was to determine whether persons who responded with high stressor-induced extralaryngeal muscle activity in a stress reactivity protocol differed from those with low muscle activity on measures of emotional and autonomic cardiovascular reactivity and personality. Method: Thirty-six vocally healthy women (18-35 years) were assigned to high and low extralaryngeal groups based on submental (SM) and infrahyoid (IH) surface electromyography (sEMG) recordings obtained during a stress reactivity protocol (high vs. low [sEMG.sub.SM] and [sEMG.sub.IH], n = 18 per subgroup; Dietrich & Verdolini Abbott, 2012). Measures included assessments of basic fear and fear of public speaking, rumination, systolic blood pressure (SBP), and personality. Results: The high [sEMG.sub.IH] group reported significantly greater basic fear across experimental phases than did the low [sEMG.sub.IH] group (p = .036). However, the high [sEMG.sub.SM] and [sEMG.sub.IH] versus low [sEMG.sub.SM] and [sEMG.sub.IH] groups did not differ on fear of public speaking, rumination, or SBP across phases. Both high [sEMG.sub.SM] and [sEMG.sub.IH] groups were characterized by significantly lower scores on Extraversion (p < .001). Conclusion: In combination with the authors' previous findings (Dietrich & Verdolini Abbott, 2012), the present findings provided robust evidence that low Extraversion was linked to stressor-induced changes in extralaryngeal functioning and that perceived fear played a contributing role., Psychological stress is a serious public health concern that poses direct and indirect health risks (Lovallo, 2005). An array of psychological, neurobiological, immunological, and physical correlates are associated with it [...]

Purpose: The aim of this study is to quantify and identify characteristic vibratory motion in typically developing prepubertal children and young adults using high-speed digital imaging. Method: The vibrations of the vocal folds were recorded from 27 children (ages 5-9 years) and 35 adults (ages 21-45 years), with high speed at 4,000 frames per second for sustained phonation. Kinematic features of amplitude periodicity, time periodicity, phase asymmetry, spatial symmetry, and glottal gap index were analyzed from the glottal area waveform across mean and standard deviation (i.e., intercycle variability) for each measure. Results: Children exhibited lower mean amplitude periodicity compared to men and women and lower time periodicity compared to men. Children and women exhibited greater variability in amplitude periodicity, time periodicity, phase asymmetry, and glottal gap index compared to men. Women had lower mean values of amplitude periodicity and time periodicity compared to men. Conclusion: Children differed both spatially but more temporally in vocal fold motion, suggesting the need for the development of children-specific kinematic norms. Results suggest more uncontrolled vibratory motion in children, reflecting changes in the vocal fold layered structure and aero-acoustic source mechanisms. Key Words: endoscopy, voice, children, Direct measurements of source characteristics of vocal fold vibrations in the pediatric population remain understudied in the field of voice science. The literature thus far on pediatric voice development consists [...]

Purpose: In this study, the authors aimed to analyze longitudinal data from high-speed digital images in normative subjects using multi-line kymography. Method: Vocally healthy subjects were divided into young (9 men and 17 women; [M.sub.age] = 27 years) and older groups (8 men and 12 women; [M.sub.age] = 73 years). From high-speed digital images of phonation at a conversational frequency kymograms were created at 5 different levels of the vocal fold and were analyzed to determine the opening/closing longitudinal phase difference, open quotient, and speed index. Then age- and gender-related differences of these parameters were analyzed statistically. Results: Young women frequently showed a pattern of posterior-to-anterior glottal opening and anterior-to-posterior glottal closure, and older women demonstrated various opening and closing patterns. Both young men and older men were similar to older women. The open quotient was maximal at the most posterior glottal level in young women, but it tended to be maximal at the anterior glottis in the other subgroups. The mean value of the 5 open quotients was largest in young women. The mean speed index had a large negative value in older subjects. Conclusion: This study provides the first information about age-related differences of longitudinal oscillatory characteristics of the vocal folds obtained with high-speed digital imaging. Key Words: voice, voice disorders, endoscopy, Videostroboscopy is widely used for the observation of vocal fold vibrations (Deliyski & Hillman, 2010; Verikas, Uloza, Bacauskiene, Gelzinis, & Kelertas, 2009). However, preceding periodic phonation with a stable fundamental [...]

Purpose: To relate vocal fold structure and kinematics to 2 acoustic measures: cepstral peak prominence (CPP) and the amplitude of the first harmonic relative to the second (H1-H2). Method: The authors used a computational, kinematic model of the medial surfaces of the vocal folds to specify features of vocal fold structure and vibration in a manner consistent with breathy voice. Four model parameters were altered: degree of vocal fold adduction, surface bulging, vibratory nodal point, and supraglottal constriction. CPP and H1 -H2 were measured from simulated glottal area, glottal flow, and acoustic waveforms and were related to the underlying vocal fold kinematics. Results: CPP decreased with increased separation of the vocal processes, whereas the nodal point location had little effect. H1 -H2 increased as a function of separation of the vocal processes in the range of 1.0 mm to 1.5 mm and decreased with separation > 1.5 mm. Conclusions: CPP is generally a function of vocal process separation. H1*-H2* (see paragraph 6 of article text for an explanation of the asterisks) will increase or decrease with vocal process separation on the basis of vocal fold shape, pivot point for the rotational mode, and supraglottal vocal tract shape, limiting its utility as an indicator of breathy voice. Future work will relate the perception of breathiness to vocal fold kinematics and acoustic measures. Key Words: voice simulation, vocal folds, breathy voice, acoustics, The purpose of this study was to establish the relation of two acoustic measures used for characterizing breathy voice to vocal fold kinematics. The possibility of using the acoustic signal [...]

Purpose: To determine the aerodynamic and acoustic effects due to a sudden change from chest to falsetto register or vice versa. It was hypothesized that the continuous change in subglottal pressure and flow rate alone (pressure-flow sweep [PFS]) can trigger a mode change in the canine larynx. Method: Ten canine larynges were each mounted over a tapered tube that supplied pressurized, heated, and humidified air. Glottographic signals were recorded during each PFS experiment, during which airflow was increased in a gradual manner for a period of 20-30 s. Results: Abrupt changes in fundamental frequency ([F.sub.0]) and mode of vibration occurred during the PFS in the passive larynx without any change in adduction or elongation. The lower frequency mode of oscillation of the vocal folds, perceptually identified as the chest register, had relatively large amplitude oscillation, significant vocal fold contact, a rich spectral content, and a relatively loud audio signal. The higher frequency mode of oscillation, perceptually identified as falsetto, had little or no vocal fold contact and a dominant first partial. Relatively abrupt [F.sub.0] changes also occurred for gradual adduction changes, with the chest register corresponding to greater adduction, falsetto to less adduction. KEY WORDS: canine larynx, register shift, chest and falsetto, pressure-flow sweep (PFS), glottal waveform, A sudden change in voice fundamental frequency ([F.sub.0]) is a biomechanical and acoustic phenomenon that can occur during phonation. Biomechanical factors such as vocal fold length, tension, thickness, and shape [...]

Purpose: To assess the effectiveness of vocal hygiene education (VHE) and voice production therapy (VP) in altering patient perception of vocal handicap in adult women with benign, bilateral phonotraumatic vocal [...]

Purpose: The purpose of this study was to describe biomechanical correlates of the surface electromyographic signal obtained during swallowing by healthy adult volunteers. Method: Seventeen healthy adults were evaluated with simultaneous videofluoroscopy and surface electromyography (sEMG) while swallowing 5 mL of liquid barium sulfate. Three biomechanical swallowing events were analyzed: hyoid elevation, pharyngeal constriction, and opening--closing of the pharyngoesophageal segment. For each biomechanical event and from the sEMG signal, the authors identified onset, peak, and offset time points. From these points, duration measures were calculated. Means and 95% confidence intervals were calculated for each measure. Subsequently, correlations were evaluated between timing aspects of the sEMG traces and each biomechanical event. Results: Swallow onset in the sEMG signal preceded the onset of all biomechanical events. All biomechanical events demonstrated a strong correspondence to the sEMG signal. The strongest relationship was between hyoid elevation--anterior displacement and the sEMG signal. Conclusions: These results suggest that the sEMG signal is a useful indicator of major biomechanical events in the swallow. Future studies should address the impact of age and disease processes, as well as bolus characteristics, on the biomechanical correlates of sEMG signals obtained during swallowing. KEY WORDS: electromyography, videofluoroscopy, swallowing assessment, Swallowing is a complex sensorimotor function that incorporates activity from multiple muscle groups in the upper aerodigestive tract. Muscle activity associated with swallowing movements may be evaluated with intramuscular or [...]

Acoustic analysis of a reading passage was used to identify the abnormal phonatory events associated with adductor spasmodic dysphonia (ADSD) pre-and postinjection of Botulinum Toxin A (Botox). Thirty-one patients (age 22 to 74 years) diagnosed with ADSD were included for study. All patients were new recipients of Botox, and the examination of their voice occurred before and after their initial injection of Botox. Acoustic events were identified from reading samples of the Rainbow Passage produced by each of the patients. These events were examined from sentences containing primarily voiced sound segments. Dependent variables included the number of phonatory breaks, frequency shifts, and aperiodic segments--all variables previously defined by the investigators. Additionally, calculated variables were made of the percentage of time these events occurred relative to the duration of the cumulative voiced segments. A sex-and age-matched control group ([+ or -] 2 years) was included for statistical comparison. Results indicated that those with ADSD produced more aberrant acoustic events than the controls. Aperiodicity was the predominant acoustic event produced during the reading, followed by frequency shifts and phonatory breaks. Within the ADSD group, the number of atypical acoustic events decreased following Botox injection. It is important that the occurrence of specific abnormal acoustic events was sufficient to differentiate the disordered speakers from the controls following as well as preceding initial Botox injection, as indicated by discriminant function analysis. This paper complements our previous work using this acoustic analysis method for defining the abnormal events present in the voice of those with ADSD and further suggests that these measures can be used in conjunction with perceptual impressions to differentiate speakers on the basis of initial severity. KEY WORDS: adductor spasmodic dysphonia, acoustic variations, connected speech, There are a number of motivations for studying the voice of those with adductor spasmodic dysphonia (ADSD), most of which concern issues of assessment and treatment. The current report is [...]

Two unique characteristics of vocal fry register are the occurrence of multiple opening and closing phases occurring within one vibratory cycle and a similar vocal fundamental frequency ([F.sub.0]) between women and men. The present study tested the hypothesis that significant differences in glottal cycle symmetry exist between women and men during modal phonation, with no significant differences during vocal fry phonation. Consistent with previous studies of modal phonation, it was also hypothesized that a vowel effect would be apparent during vocal fry phonation. Five women and 5 men sustained modal and vocal fry phonations in four vowel contexts (/a, ae, u, i/). Vocal [F.sub.0], duration of opening and closing phase, and contact symmetry (speed quotient) were derived from electroglottographic (EGG) waveforms. Both female and male speakers demonstrated significantly higher SQ values in vocal fry register than in their modal register, indicating a longer opening-phase duration per glottal cycle. Women demonstrated a significantly greater increase in SQ during vocal fry phonations than men, indicating greater asymmetry between opening and closing durations. The results confirmed that gender differences in vocal fold contact behavior not only exist during modal register but also during vocal fry register. No vowel effects on vocal fold contact behavior as inferred using the SQ measure were found for either modal or vocal fry registers. Possible contributing factors to multiple opening and closing phases occurring within a vibratory cycle are discussed. KEY WORDS: electroglottograph, gender, modal register, vocal fry, vocal fold contact, Alterations in the vibratory properties of the vocal folds give rise to acoustically and perceptually distinct vocal qualities (or registers) (Daniloff, Shuckers, & Feth, 1980). Vocal fry is one such [...]

Stevens (1991) has suggested that, while speakers control glottal apertures in producing consonants, the buildup of intraoral pressure during an oral closure creates decreases in transglottal flow, which can, in itself, reduce or halt vocal fold vibrations. The object of this study was to determine whether speakers can take advantage of such pressure effects in controlling the voicing attributes of intervocalic stops. Intraoral pressure, vocal fold vibration (Lx portions of electroglottograms), and electromyographic (EMG) activity of the orbicularis oris inferior were monitored for 6 subjects while they produced at "slow," "normal," and "fast" speaking rates utterances containing intervocalic stops /p/ and /b/. Product-moment correlations between the intervocalic pressure rises and the amplitude contour of Lx showed strong negative relationships at normal-to-fast rates of speech. However, this relationship was not maintained at slower rates, where decreases in the amplitude of Lx sometimes occurred before the onset of EMG activity in the labial adductor. The findings suggest that, at normal-to-fast rates of speech, speakers can use the passive effects of pressure in controlling vocal fold vibration for stop consonants. KEY WORDS: speech rate, phonation, speech aerodynamics, speech motor control, articulation, Abnormalities in the control of voicing have been reported for a number of speech pathologies including verbal apraxia (e.g., Itoh et al., 1982), certain dysarthrias (Kent, Netsell, & Abbs, 1979; [...]

Adductor spasmodic dysphonia (ADSD) is an idiopathic focal laryngeal movement disorder causing involuntary and uncontrollable spasms in the vocal fold musculature, primarily during voice onset. Although phonatory instability has been reported through clinical observation and empirical study, no examination of phonatory performance consistency in ADSD has been done. Phonatory instability refers to phonatory unsteadiness and has been previously defined by the presence of acoustic aberrations during speech. Performance consistency pertains to variations in these phonatory aberrations across repeated trials or over time. This study focused on the phonatory performance consistency of those with ADSD by using three acoustic measures of phonatory instability. Twenty patients with ADSD were recorded during three trials of reading a standard passage. Eight of the 20 patients were recorded twice during two separate recording sessions held approximately 6 months apart. The number of phonatory breaks, frequency shifts, and aperiodic segments were the dependent measures. Data were subjected to inferential statistical analysis to test for significant differences among the measures in two conditions: across three trials produced within one recording session and across multiple trials produced during two distinct recording sessions. No significant differences were found for any of the measures either as a function of trials recorded on the same day or across the two recording sessions. The data suggest a need for describing phonatory instability and performance consistency as separate entities with regard to neurological voice disorders. KEY WORDS: adductor spasmodic dysphonia, phonatory instability, performance consistency, Adductor spasmodic dysphonia (ADSD) is considered a focal dystonia that is localized specifically to the laryngeal muscles (Aminoff, Dedo, & Izdebski, 1978; Davidson & Ludlow, 1996; Dedo, Townsend, & Izdebski, [...]

Twenty-four normally speaking subjects had to utter the test word /tatatas/ with different stress patterns repeatedly. Auditory feedback was provided by headphones and was shifted downwards in frequency during randomly selected trials while the subjects were speaking the complete test word. If the first syllable was long stressed, fundamental frequency of the vowel significantly increased by 2 Hz (corresponding to 25.5 cents) under frequency-shifted auditory feedback of .5 octave downwards, whereas under a shift of one semitone downwards a trend of an increase could be observed. If the first syllable was unstressed, fundamental frequency remained unaffected. Regarding the second syllable, significant increases or a trend for an increase of fundamental frequency was found in both shifting conditions. Results indicate a negative feedback mechanism that controls the fundamental frequency via auditory feedback in speech production. However, within a syllable a response could be found only if the syllable duration was long enough. Compensation for frequency-shifted auditory feedback still is quite imperfect. It is concluded that control of fundamental frequency is rather important on a suprasegmental level. KEY WORDS: fundamental frequency, pitch, frequency-shifted auditory feedback, auditory control, prosody, Deficits in the speech of postlingually deafened persons (Cowie, Douglas-Cowie, & Kerr, 1982) suggest that auditory feedback plays a significant role in speech production. The deterioration of speech takes place [...]