Maximum Phonational Frequency Range Research Articles

Analysis of Voice Quality After Thyroid Surgery

Voice changes are a common complication after a thyroidectomy, which isa surgical procedure involving partial or total removal of the thyroid gland. The main objective of this work is to examine the possible voice disorders after thyroid surgery. More precisely, it is an investigation of partial and total thyroidectomy, as well as the effects that cancerous and noncancerous thyroid glands can have regarding postsurgical vocal and their association with age and gender. Patients were evaluated using acoustic voice parameters, including harmonics-to-noise ratio (HNR), fundamental frequency (F0), jitter, speaker phonation frequency (SPF) range, cepstral peak prominence (CPP), maximum phonational frequency range (MPFR), and shimmer at the preoperative stage and postoperatively at the 1day, and first-month stages. Results demonstrated a significant change in F0 parameters, SPF range, and CPP feature 1 month after surgery, depending on the type of thyroidectomy and thyroid pathology. No significant changes were observed in the HNR, shimmer, and jitter features. Age was associated with the CPP parameter in the entire sample. In contrast, the MPFR parameter was also related to the type of thyroidectomy in the entire sample. However, maximum F0 was significantly associated with the type of thyroidectomy, specifically in the female sample. Results indicated that a thyroidectomy can have a negative impact on voice quality. The age and type of thyroidectomy performed are not responsible for this change. Potentially this change can be due to factors such as nerve damage or the subjects' experience, such as job, anxiety, and their physical condition, as well as treatments they may have undergone before thyroidectomy. Further efforts are needed to fully understand the background of voice changes after thyroidectomy.

The Effect of Vocal Training on Vocal Quality in Chinese Singing Students

The purpose of this study was to investigate the effect of vocal training on singing voice in Chinese folk song major students. A longitudinal study over a two years' period (four consecutive semesters) was conducted to observe the effects. Ten college students majoring in Chinese folk music (seven females and three males; age range: 19-21 years) were recorded three times while singing, at the beginning of the first, third, and fifth semesters. Acoustical parameters including maximum phonational frequency range (MPFR), sound pressure level (SPL), intonation accuracy and long-term average spectrum (LTAS) were measured to evaluate the effects. Results indicated that vocal training had a significant effect on MPFR, and SPL increased as vocal training progressed. A slight improvement in intonation accuracy was observed during training period, and LTAS changes as a function of training were detected in some subjects. This longitudinal study indicates that the effect of vocal training on vocal quality improvement can be observed in Chinese singing students and evaluated by measuring certain acoustic parameters.

Lip Trill Effects on Vocal Function, Vocal Pitch, and Harmonics-to-Noise Ratio: A Multiple Baseline Study of Three Vocally Healthy Females.

The lip trill is a semi-occluded vocal tract exercise found to have positive outcomes on vocal parameters of healthy individuals after a single session. However, the effect of several lip trill sessions has not been studied. This study investigated the effect of a 3- to 4-week lip trill exercise program on Maximum Phonation Time (MPT), Maximum Phonation Frequency Range (MPFR), Harmonics-to-Noise Ratio (HNR), and mean Speaking Fundamental Frequency (mean SFF). Three vocally untrained healthy females with perceptually normal voices participated in a multiple-baseline, single-case experimental research. Five to seven direct training sessions were randomly assigned. Self-implementation was encouraged thereafter. Participants were assessed on all outcome measures for 15 sessions. Data were visualized and inspected. Cohen's d was also derived using Standardized Mean Difference for single-subject research. Visual and statistical analyses revealed a decreased MPT when training was introduced, increased MPFR variability during the training phase, and increased stability in mean SFF post-training. Perceived effects include vocal freedom, decreased laryngeal stress, and vocal conditioning. Vocal outcomes in one participant yielded a significant effect on MPFR and mean SFF and a small effect on HNR. There is evidence of lip trill effect on pitch control and vocal conditioning. Findings also revealed that motivation, exercise frequency, and adherence could contribute to positive gains in vocally healthy speakers. Further investigation in consideration of the study findings and limitations is warranted.

LSVT LOUD® Applied to an Adult With Cerebral Palsy: Acoustic Findings

A 36-year-old female with severe spastic dysarthria participated in this study. She received 4 weeks of individual, intensive voice-focused treatment. Voice recordings were conducted at three baseline points, immediately posttreatment, and at a 4-month follow-up. The primary outcome variables were selected acoustic measures of vocal function: sound pressure level (SPL), mean fundamental frequency (F0), maximum phonation time (MPT), jitter, shimmer, noise-to-harmonics ratio (NHR), and maximum phonation frequency range (MPFR). Significant pre-to-posttreatment changes ( p < .05) were found for most acoustic variables. All acoustic gains, except for MPFR, were maintained at the 4-month follow-up. The significant posttreatment changes in the majority of the acoustic measures analyzed suggest that intensive voice-focused treatment may have the potential to improve vocal function in adults with severe spastic dysarthria secondary to cerebral palsy (CP). Evidence-based treatment options for voice disorders in adults with CP are limited. Results emphasize the need for more studies with this population.

Effects of Coaching and Repeated Trials on Maximum Phonational Frequency Range in Children

Maximum phonational frequency range (MPFR) is the frequency range from the lowest to the highest pitch that an individual can produce. This study investigated the effects of coaching and repeated trials on MPFR in a group of school-age children. Thirty girls aged 6-11 years were randomly assigned into two groups: coaching and non-coaching. All of the participants produced the lowest and the highest phonational frequency for 10 times each. The participants in the coaching group were prompted by the clinician with verbal encouragement and a visual cue (hand-sweeping) to produce their maximum performance. The participants in the non-coaching group were simply asked to repeat the task 10 times. The clinician's coaching helped the participants in the coaching group reach their MPFR in fewer trials. The MPFRs elicited in 10 trials were significantly greater than those elicited in fewer trials. These findings suggested that coaching and repeated trials could facilitate the elicitation of MPFR more efficiently.

Quantitative Analysis of Voice in Parkinson Disease Compared to Motor Performance: A Pilot Study.

Characteristic features of hypokinetic dysarthria develop in Parkinson disease (PD). We hypothesized that quantified acoustic changes of voice might provide a correlate of disease severity. To determine if there are significant differences in acoustic measures of voice between mild and moderate PD; 2) To evaluate correlations between acoustic parameters of voice and subtests of the UPDRS in mild and moderate PD. Twenty six participants with PD underwent vocal acoustic testing while off PD medication, for comparison to 22 healthy controls. Participants with PD were divided into two groups based upon UPDRS activities of daily living (ADL) ratings: summed scores were used to define mild and moderate PD. Participants voiced /i/ ("ee") at comfort, high, and low pitch (3 trials/pitch). The CSpeech Waveform Analysis Program was used to analyze cycle-to-cycle frequency ("jitter") and amplitude ("shimmer") irregularities of the vocal signal, signal-to-noise ratio, and maximum phonation frequency range converted to semitones. Sections of UPDRS scores were correlated to acoustic variables of voice. Key findings included a significant difference between the semitone range of the control subjects and the moderate PD group (p = 0.036). Further analyses revealed significant differences in semitone range for males between the controls vs. mild PD (p = 0.014), and controls vs. moderate PD (p = 0.005). Significant correlations were also found between acoustic findings and both the ADL and motor portions of the UPDRS. Acoustic analysis of voice, particularly frequency range, may provide a quantifiable correlate of disease progression in PD.

Hoarseness after thyroidectomy: blame the endocrine surgeon alone?

Hoarseness is a postoperative complication of thyroidectomy, mostly due to damage to the recurrent laryngeal nerve (RLN). Hoarseness may also be brought about via vocal cord dysfunction (VCD) due to injury of the vocal cords from manipulations during anesthesia, as well as from psychogenic disorders and respiratory and upper-GI related infections. We reviewed the literature aiming to explore these potential surgical and non-surgical causes of hoarseness beyond thyroidectomy and the role of the endocrine surgeon. Is he/she alone to blame? The MEDLINE/PubMed database was searched for publications with the medical subject heading "hoarseness" and keywords "thyroidectomy", "RLN", "VCD" or "intubation". We restricted our search till up to May 2013. In our final review we included 80 articles and abstracts that were accessible and available in English. We demonstrated the incidence of hoarseness stemming from surgical and non-surgical causes and also highlighted the role of intubation as a potential cause of injury-related VCD. Hoarseness is a relatively common complication of thyroidectomy, which can be attributed to many factors including surgeon's error or injuries during intubation as well as to other non-surgical causes. However, compared to procedures such as cervical spine surgery, mediastinal surgery, esophagectomy and endarterectomy, thyroidectomy would seem to be a procedure with a relatively low rate of recurrent laryngeal nerve palsies (RLNPs). It is often difficult to determine whether the degree of hoarseness after thyroidectomy should be attributed only the surgical procedure itself or to other causes, for example intubation and extubation maneuvers. The differential diagnosis of postoperative hoarseness requires the use of specific tools, such as stroboscopy and intra- and extralaryngeal electromyography, while methods like acoustic voice analysis, with estimation of maximum phonation time and phonation frequency range, can distinguish between objective and subjective deterioration in the voice. The importance of medical history should be also emphasized.

Voice acoustic profile of males exposed to occupational infrasound and low-frequency noise

Background: Vibroacoustic disease (VAD) is a systematic pathology characterized by the abnormal growth of extra-cellular matrices in the absence of inflammatory processes, namely collagen and elastin, both of which are abundant in the basement membrane zone of the vocal folds. VAD can develop due to long-term exposure to infrasound and low-frequency noise (ILFN, < 500 Hz). Mendes et al. (2006, 2008 and 2012) revealed that ILFN-exposed males and females presented an increased fundamental frequency (F 0 ), decreased jitter %, and reduced maximum phonation frequency range, when compared with normative data. Temporal measures of maximum phonation time and S/Z ratio were generally reduced. Study Aims: Herein, the same voice acoustic parameters of 48 males, 36 airline pilots and 12 cabin crewmembers (age range 25-60 years) were studied, and the effects and interaction of age and years of ILFN exposure were investigated within those parameters. ILFN-exposure time (i.e. years of professional activity) ranged from 3.5 to 36 years. Materials and Methods: Spoken and sung phonatory tasks were recorded with a DA-P1 Tascam DAT and a C420III PP AKG head-worn microphone, positioned at 3 cm from the mouth. Acoustic analyses were performed using KayPENTAX Computer Speech Lab and Multi-Dimensional Voice Program. Results: Results revealed that even though pilots and cabin crewmembers were exposed to occupational environments with distinct (ILFN-rich) acoustical frequency distributions and sound pressure levels, differences in the vocal acoustic parameters were not evident. Analyzing data from both professional groups (N = 48) revealed that F 0 increased significantly with the number of years of professional activity. Conclusion: These results strongly suggest that the number of years of professional activity (i.e. total ILFN exposure time) had a significant effect on F 0 . Furthermore, they may reflect the histological changes specifically observed on the vocal folds of ILFN-exposed professionals.

Fundamental frequency in English and Mandarin.

It has been suggested that Mandarin, as a tone language, uses a larger F0 range than English. This study addresses two questions: (1) Do English and Mandarin F0 profiles differ? (2) How does the type of voice sample which is measured affect this F0 characterization and language comparison? Native speakers of English or Mandarin produced a variety of speech samples intended to elicit a wide range of F0s. Maximum phonation frequency range was measured from pitch sweeps, and speaking F0 was measured from readings of the Rainbow passage, isolated words with various intonations, and a dramatic story. Cepstral pitchtracking was used to log the entire F0 contour for each utterance, and various measures were computed. Preliminary results suggest, first, that the maximum phonation frequency ranges are the same for the two languages; second, that in reading Mandarin speakers use a higher mean F0, but at the same time English speakers use higher maximum F0 and wider range of F0; and third, that these differences do not depend on the speech samples being compared. [Work supported by NSF.]

The relative effectiveness of vocal hygiene training and vocal function exercises in preventing voice disorders in primary school teachers

Voice disorders in teachers have a significant impact on their occupational functioning and well being. Teachers are believed to have a high prevalence of voice problems because of the unfavourable acoustic environments in which they work and the high vocal demands and stress levels associated with teaching. Although the types of voice problems teachers experience should be preventable because they are caused by factors that teachers can change, there is limited information available regarding the effectiveness of different preventative strategies. Therefore, the aim of this study was to investigate the effectiveness of vocal hygiene training (VH) and vocal function exercises (VFE) in reducing vocal symptoms and vocal misuse, and increasing knowledge of voice care, maximum phonation time, and maximum phonational frequency range in school teachers. Thirty-seven teachers from four schools in Melbourne, Australia, participated in the study. Schools were randomly allocated to one of three groups: VH, VFE, and no-treatment control. The VH and VFE participants reported improved vocal characteristics and voice knowledge after training while the control group showed deterioration on most variables. The VH participants showed greater improvements than the VFE participants. These findings indicate that preventative voice training for teachers is likely to be effective.

Padrões acústicos da voz em indivíduos com a doença vibroacústica

Background: Long-term low frequency noise exposure (LFN) (≤ 500Hz, including infrasound) may lead to the development of vibroacoustic disease (VAD), a systemic pathology characterized by the abnormal growth of extra-cellular matrices. The respiratory system is a target for LFN. Fibrosis of the respiratory tract epithelia was observed in VAD patients through biopsy, and confirmed in animal models exposed to LFN. Voice acoustic analysis can detect vocal fold variations of mass, tension, muscular and neural activity. Frequency perturbation (jitter), amplitude perturbation (shimmer) and harmonic-to-noise ratio (HNR) are used in the evaluation of the vocal function, and can be indicators of the presence and degree of severity of vocal pathology. Since the respiratory system is the energy source of the phonation process, this raises questions about the effects of VAD on voice production. The purpose of this study was to determine if voice acoustic parameters of VAD patients are different from normative data. Methods: Nine individuals (5 males and 4 females) diagnosed with VAD were recorded performing spoken and sung tasks. The spoken tasks included sustaining vowels and fricatives. The sung tasks consisted of maximum phonational frequency range (MPFR). Voice acoustic parameters analysed were: fundamental frequency (F0), jitter, shimmer, HNR and temporal measures. Results: Compared with normative data, both males and females diagnosed with VAD exhibited increased F0, shimmer and HNR. Jitter, MPFR and one temporal measure were reduced. Conclusions: VAD individuals presented voice acoustic parameter differences in spectral, temporal and perturbation measures, which may be indicative of small morphological changes in the phonatory system.Rev Port Pneumol 2006; XII (4): 375-382

Voice acoustic patterns of patients diagnosed with vibroacoustic disease

BackgroundLong-term low frequency noise exposure (LFN) (≤500Hz, including infrasound) may lead to the development of vibroacoustic disease (VAD), a systemic pathology characterized by the abnormal growth of extra-cellular matrices. The respiratory system is a target for LFN. Fibrosis of the respiratory tract epithelia was observed in VAD patients through biopsy, and confirmed in animal models exposed to LFN. Voice acoustic analysis can detect vocal fold variations of mass, tension, muscular and neural activity. Frequency perturbation (jitter), amplitude perturbation (shimmer) and harmonicto- noise ratio (HNR) are used in the evaluation of the vocal function, and can be indicators of the presence and degree of severity of vocal pathology. Since the respiratory system is the energy source of the phonation process, this raises questions about the effects of VAD on voice production. The purpose of this study was to determine if voice acoustic parameters of VAD patients are different from normative data. MethodsNine individuals (5 males and 4 females) diagnosed with VAD were recorded performing spoken and sung tasks. The spoken tasks included sustaining vowels and fricatives. The sung tasks consisted of maximum phonational frequency range (MPFR). Voice acoustic parameters analysed were: fundamental frequency (F0), jitter, shimmer, HNR and temporal measures. ResultsCompared with normative data, both males and females diagnosed with VAD exhibited increased F0, shimmer and HNR. Jitter, MPFR and one temporal measure were reduced. ConclusionsVAD individuals presented voice acoustic parameter differences in spectral, temporal and perturbation measures, which may be indicative of small morphological changes in the phonatory system.

Effects of vocal training on the acoustic parameters of the singing voice

Summary Vocal training (VT) has, in part, been associated with the distinctions in the physiological, acoustic, and perceptual parameters found in singers' voices versus the voices of nonsingers. This study provides information on the changes in the singing voice as a function of VT over time. Fourteen college voice majors (12 females and 2 males; age range, 17–20 years) were recorded while singing, once a semester, for four consecutive semesters. Acoustic measures included fundamental frequency (F 0) and sound pressure level (SPL) of the 10% and 90% levels of the maximum phonational frequency range (MPFR), vibrato pulses per second, vibrato amplitude variation, and the presence of the singer's formant. Results indicated that VT had a significant effect on the MPFR. F 0 and SPL of the 90% level of the MPFR and the 90–10% range increased significantly as VT progressed. However, no vibrato or singers' formant differences were detected as a function of training. This longitudinal study not only validates previous cross-sectional research, ie, that VT has a significant effect on the singing voice, but also it demonstrates that these effects can be acoustically detected by the fourth semester of college vocal training.

Mid-Basal-to-Ceiling Versus Mid-Ceiling-to-Basal Elicitation of Maximum Phonational Frequency Range

The purpose of this study was to investigate if there was an effect of task on the determination of maximum phonational frequency range (MPFR). Two tasks commonly used to elicit MPFR in clinical voice evaluations were compared. Normal adult females ( n = 30) were examined. No statistically significant effect of task was found. Both tasks (mid-basal-to-ceiling and mid-ceiling-to-basal) were found to have a high positive correlation (0.89). Implications of the use on one task to determine maximum phonational frequency range are discussed, as is the possibility of a task effect on determination of other voice parameters.

Speech Science: An Integrated Approach to Theory and Clinical Practice

Speech Science: An Integrated Approach to Theory and Clinical Practice

Voice characteristics in the progression of Parkinson's disease.

This study examined the acoustic and perceptual voice characteristics of patients with Parkinson's disease according to disease severity. The perceptual and acoustic voice characteristics of 30 patients with early stage PD and 30 patients with later stage PD were compared with data from 30 normal control subjects. Voice recordings consisted of prolongation of the vowel /a/, scale singing, and a 1-min monologue. In comparison with controls and previously published normative data, both early and later stage PD patients' voices were characterized perceptually by limited pitch and loudness variability, breathiness, harshness and reduced loudness. High modal pitch levels also characterized the voices of males in both early and later stages of PD. Acoustically, the voices of both groups of PD patients demonstrated lower mean intensity levels and reduced maximum phonational frequency ranges in comparison with normative data. Although less clear, the present data also suggested that the PD patients' voices were characterized by excess jitter, a high-speaking fundamental frequency for males and a reduced fundamental frequency variability for females. While several of these voice features did not appear to deteriorate with disease progression (i.e. harshness, high modal pitch and speaking fundamental frequency in males, fundamental frequency variability in females, low intensity and jitter), breathiness, monopitch and monoloudness, low loudness and reduced maximum phonational frequency range were all worse in the later stages of PD. Tremor was the sole voice feature which was associated only with later stage PD.

The effect of task on determination of maximum phonational frequency range

The purpose of this study was to investigate if there was an effect of task on determination of maximum phonational frequency range (MPFR). Two tasks commonly used to elicit MPFR in clinical voice evaluations were compared. Normal adult females (N = 30) were examined. No statistically significant effect of task was found. Both tasks (glissando and discrete-step) were found to have a high positive correlation (0.84). Implications of the use of one task for determination of maximum phonational frequency range are discussed, as is the possibility of a task effect on determination of other voice parameters.

Effects of laryngeal endoscopy on the vocal performance of young adult females with normal voices.

This study investigated changes in maximum phonation time and acoustic and perceptual measures of voice following topical anesthesia and laryngeal endoscopy with the flexible endoscope. Forty-four females, aged 18-33 years and with normal voices, performed four vocal tasks: (a) 3-second /i/ prolongation, (b) maximum phonation time on /i/, (c) stepwise scale-singing, and (d) reading a standard passage. Subjects performed these tasks prior to anesthesia, after anesthesia, and again during laryngeal endoscopy. Voice samples were analyzed forjitter, shimmer, harmonic-to-noise ratio, speaking fundamental frequency, maximum phonational frequency range, maximum phonation time, harshness, and breathiness. Results demonstrated significant reductions in maximum phonational frequency range following anesthesia and, during laryngeal endoscopy, reductions in maximum phonation time and increases in speaking fundamental frequency, minimum fundamental frequency on scale-singing, and breathiness. Clinicians using laryngeal endoscopy for evaluation and management of vocal dysfunction should, therefore, consider the possible effects of these procedures on vocal functioning.

Paradoxical glottal closure mechanism associated with postintubation granuloma

This report describes a paradoxical glottal closure mechanism that was documented in a patient with large, bilateral postintubation granulomas. This pathology existed without any perceptual deviation in voice quality. Although the patient exhibited a reduction in his maximum phonational frequency range (MPFR), an acoustic assessment of fundamental frequency across a variety of vocal tasks and jitter ratios (JRs) for sustained vowels, as well as measures of maximum phonation time, were within normal limits. Videodocumentation of the laryngeal mechanism revealed a glottal closure mechanism which permitted normal vocal fold adduction despite these bilateral lesions. The basis of the closure mechanism is discussed and comment regarding management of these lesions is presented. This report describes a paradoxical glottal closure mechanism that was documented in a patient with large, bilateral postintubation granulomas. This pathology existed without any perceptual deviation in voice quality. Although the patient exhibited a reduction in his maximum phonational frequency range (MPFR), an acoustic assessment of fundamental frequency across a variety of vocal tasks and jitter ratios (JRs) for sustained vowels, as well as measures of maximum phonation time, were within normal limits. Videodocumentation of the laryngeal mechanism revealed a glottal closure mechanism which permitted normal vocal fold adduction despite these bilateral lesions. The basis of the closure mechanism is discussed and comment regarding management of these lesions is presented.

Maximum phonational frequency range capabilities of women's voices with advancing age.

Maximum phonational frequency range capabilities of women's voices with advancing age.