Phonatory Activity Research Articles

Quantifying the Occupational Voice Use of Teachers.

The teaching profession is a high-voice use occupation at elevated risk for developing voice disorders. Continued research on teachers' vocal demands is necessary to advocate for and establish vocal health programs. This study quantified ambulatory vocal dose measures for teachers during both on- and off-work periods, comparing their occupational voice use to that in other studies that have reported percent phonation ranging from 17% to 30%. Participants included 26 full-time, female school teachers between 23 and 55 years of age across multiple grades and subjects, including individuals with and without a voice disorder. Ambulatory voice data were collected from weeklong voice monitoring that recorded phonatory activity through anterior neck-surface vibration. Three vocal dose measures-time, cycle, and distance doses-were computed for each participant for three time periods: on-work weekdays, off-work weekdays, and off-work weekend days. The teachers' average percent phonation was 16.2% on-work weekdays, 8.4% off-work weekdays, and 8.0% off-work weekend days. No statistically significant differences for vocal dose measures were found between off-work weekdays and weekend days. Overall, all vocal dose measures were approximately 2 times higher during work relative to off-work time periods. This study provides values for vocal dose measures for school teachers using ambulatory voice-monitoring technology. The vocal demands of this particular teacher sample and voice activity detection algorithm are potential factors contributing to percent phonation values on the lower end of the range reported in the literature. Future work is needed to continue to understand occupational voice use and its associated risks related to voice health, with the ultimate goal of preventing and managing voice disorders in individuals engaged in high-risk occupations.

Daily Phonatory Activity of Individuals With Parkinson's Disease

This study evaluated the amount of phonatory activity of Persons with Parkinson disease (PwPD) compared to adults without Parkinson's disease measured over 3 days. The relationship between the amount of phonatory activity and Voice Handicap Index (VHI) total score was assessed as were differences in voicing activity across 3 days of data collection. Fifteen PwPD receiving dopaminergic medication and fifteen age and sex matched adults without Parkinson's disease completed the VHI and then wore a VocaLog vocal monitor (VM) for 3 consecutive days. From the VM data, the number of 1-second windows with dB sound pressure level > 0 were summed as a measure of phonatory activity (PA) and reported relative to the time the VM was worn (%PA). The percentage of time the VM was worn did not differ between groups or across days. The PwPD had statistically significantly fewer minutes of PA per day than controls (F = 21.782, P < 0.001) by 54 minutes on average. The %PA also differed significantly (F = 31.825, P < 0.001) with a mean of 11.1% for PwPD and 18.6% for controls. Neither PA nor %PA differed across the 3 days of vocal monitoring. VHI total score was significantly correlated with PA (r = -0.436, P = 0.016) and %PA (r = -0.534, P = 0.002) for all participants. The results indicate that PwPD engaged in less verbal communication in their daily environment compared to adults without Parkinson's disease. The findings support reports in the literature indicating that PwPD often have reduced communication participation. Measures such as %PA could serve as a quantifiable metric in future studies assessing communication changes in PwPD as a function of disease progression or therapeutic interventions.

Values of laryngeal stroboscopy in patients with chronic laryngitis exposed to occupational factors

Values of laryngeal stroboscopy in patients with chronic laryngitis exposed to occupational factors

Mathematics of a Mantra

Abstract This paper aims to examine the enunciation (uccāraṇa-kāla) time intervals for śrīvidyā pañcadaśī, a fifteen seed-syllable mantra (bīja-mantra) related to the homonymous śākta school Śrīvidyā or Traipuradarśaṇa. Following the indications provided in the Yoginīhṛdaya, with Dīpikā commentary by Amṛtānanda, and the Varivasyāraharasya by Bhāskararāya with Prakāśa auto-commentary, the research finds that these durations are not arbitrary at all but rather the result of a rigorous assessment. Moreover, the duration values suggest a specific conceptual goal that the mathematical rigor manifested by the authors seeks to fulfil: the progressive diminution of time intervals in order to achieve an atemporal dimension. The choice of the units of measurement itself is designed to meet this metaphysical and ritual need. By counting the intervals (both relative and overall) of mantra recitation, it is also possible to confirm the resonance nature of the sounds following nasalisations, sounds conceived by the authors as entirely independent of the reciter’s phonatory activity.

Singing voice: acoustic parameters after vocal warm-up and cool-down

Purpose: The aim of this study was to evaluate the effect of the vocal warm-up and cool-down on the singing voice through Fundamental Frequency (F0), Jitter, Shimmer and harmonics-to-noise ratio (HNR).Methods: Thirty-two female singing students were recorded four times while uttering the vowel [a] for at least 5''. The first two recordings were collected before and after a vocal warm-up session and the last two before and after a vocal cool-down session. Between those sessions the participants underwent an intense vocal activity.Results: Results showed significant variations in the average values of the parameters measured. The mean value of the F0 after intense vocal activity turned to be higher than the one measured before the warm-up session, as well as the mean F0 measured after singing compared to the one measured after the vocal warm-up. On the other end, the mean F0 after the vocal cool-down resulted to be lower than that measured before. After the vocal warm-up session Jitter and Shimmer decreased while HNR increased. In addition, a decrease was detected in comparison with the average value of Jitter and Shimmer before vocal warm-up and after vocal cool-down, whereas HNR increased. There was also a decrease between the Shimmer before the vocal warm-up and after an intense phonatory activity while HNR increased.Conclusions: Our study highlights the effect of the vocal warm-up on acoustic parameters. The reduction in F0 observed after the cool-down session confirms its positive effect in helping professional vocal recovery and reducing vocal fold tension.

Evaluation of the results of the prevention program "Protect your voice" implemented by The Greater Poland Center of Occupational Medicine of Poznan

The aim of the study was to evaluate the rationale for training in voice emission and voice prophylaxis among teachers and to assess the effects of voice disorders rehabilitation in the selected group of teachers participating in the program "Protect your voice." An anonymous survey was conducted among 463 teachers participating in the training part of the program. The effectivness of rehabilitation of teachers with occupational voice disorders was evaluated among 51 subjects (average age: 43 years) taking part in diagnostic and rehabilitation part of the program. Phonation voice exercises with speech therapist and physiotherapy (iontophoresis, inhalations and elektrostimulation) were administered. Evaluation of rehabilitation was based on phoniatric examination, including videostroboscopy and statistical calculations. The survey showed that among teachers there is high demand (98%) for training in proper voice emission, hygiene and prevention of voice. The effectiveness of rehabilitation has been confirmed by the observed improvements in phonatory activities of larynx, proper breathing during phonation (p = 0.0000), the voice quality (p = 0.0022), prolonged phonation time (an average of 1.39 s), increased number of people who correctly activated resonators (p = 0.0000) and increased number of people with phonation without excesive muscle tension of the neck. The results indicate that among all the professionally active teachers, there is a need for regular training of proper voice emission and vocal hygiene and then conduct individually phonation and breathing exercises, supported by the physiotherapy. This should be an effective method of voice disorders prevention in teachers. Med Pr 2017;68(5):593-603.

Phonatory Activity after Supracricoid Partial Laryngectomy

Phonatory Activity after Supracricoid Partial Laryngectomy Aim of this study is to evaluate the phonatory activity following reconstructive laryngectomy and the real recovery possibilities offered by rehabilitation techniques. We examined 24 patients treated with partial laryngectomy (14 males and 10 females, between the ages of 50 and 64 years, mean age of 56) with deglutition and voice difficulties after surgery. 14 patients had undergone cricohyoidoepiglottopexy (CHEP), with preservation of a single arytenoids. 10 subjects had undergone cricohyoidopexy (CHP), with preservation of a single arytenoid. Before and after speech therapy, each subject underwent laryngostroboscopy with flexible endoscope, spectography and aerodynamic evaluations. Each subject was asked to complete the questionnaire of voice perceptual self-evaluation: Voice Handicap Index (VHI). Our experience shows how substitution voice in supracricoid laryngectomy is characterized by remarkable noise quality (in the CHEP the phonatory duration was 8.8 sec, subglottic pressure 14.21 cm H2O, phonatory flow 0.336 l/sec instead in the CHP the phonatory duration was 8.5 sec, the subglottic pressure 6.46 cm H2O and the phonatory flow 0.289 l/sec). This causes a clearly difficult voice recovery, especially from a psychological point of view. In addition to evaluate verbal intelligibility, the speech therapist has to consider that it can be difficult for the patient to accept his/her new vocal timbre.

Testing of the VocaLog Vocal Monitor

To elucidate capabilities and limitations of the VocaLog, a device marketed to log-calibrated dB sound pressure level (SPL). The study design varied depending on the experiment. All were prospective. Some were case series, and others were cohort studies without controls. Experiments were conducted to determine (1) whether the VocaLog logged phonatory activity and silence when it should, (2) if nonphonatory activities were detected, (3) correlation of VocaLog dB values to an external sound level meter (SLM), and (4) accuracy of phonation time (PT) and speaking time (ST) estimates from the VocaLog. Silence and phonatory activity were logged as such nearly 100% of the time. Nonphonatory activities were sometimes detected as dB values, including coughs, throat clear, belching, and swallows. The dB values from the VocaLog were strongly correlated with dB SPL from an external SLM. When on the neck, the device rarely picked up external sounds when the external noise was between 85 and 103dB SPL. The VocaLog gave a reasonable estimate of ST but overestimated PT. Overall, the VocaLog holds promise as means of indexing vocal loudness via calibrated dB SPL levels. However, some nonphonatory activity is also likely to be logged. The device provides a reasonable estimate of ST, but not PT.

Reshaping Phonetics

This paper proposes that the fundamental categories in phonetics are not “segment” and “suprasegmental”, but rather “segment” and “phonation”, which result from the articulatory activities in the vocal tract and the phonatory activities at the glottis respectively. The “phonatory activities” consist of four sub-categories: phonationals (phonation modes), sub-phonationals (sub-phonation modes), supra-phonationals and quasi-phonationals. There are six types and twelve sub-types of phonation modes in linguistic phonetics, which can be used to define three tonal registers in syllabics (syllable-based phonology). Under such an analysis, pitch and length are not suprasegmentals, but rather supra-phonationals. The so-called quasi-phonationals refer to two kinds of laryngeal activities, implosive and ejective, which are classified as “non-pulmonic” consonants in traditional phonetics. This new “vocal tract – laryngeal” dichotomy system not only covers the former “segment and suprasegmental” system, but can serve to categorize the world’s languages and to illuminate the transition from polysyllabic accentual languages to monosyllabic tonal languages. Finally, a hypothesis that breathy voice results from humid climates is put forward.

Reshaping Phonetics

This paper proposes that the fundamental categories in phonetics are not “segment” and “suprasegmental”, but rather “segment” and “phonation”, which result from the articulatory activities in the vocal tract and the phonatory activities at the glottis respectively. The “phonatory activities” consist of four sub-categories: phonationals (phonation modes), sub-phonationals (sub-phonation modes), supra-phonationals and quasi-phonationals. There are six types and twelve sub-types of phonation modes in linguistic phonetics, which can be used to define three tonal registers in syllabics (syllable-based phonology). Under such an analysis, pitch and length are not suprasegmentals, but rather supra-phonationals. The so-called quasi-phonationals refer to two kinds of laryngeal activities, implosive and ejective, which are classified as “non-pulmonic” consonants in traditional phonetics. This new “vocal tract – laryngeal” dichotomy system not only covers the former “segment and suprasegmental” system, but can serve to categorize the world’s languages and to illuminate the transition from polysyllabic accentual languages to monosyllabic tonal languages. Finally, a hypothesis that breathy voice results from humid climates is put forward.

Arytenoid adduction: controlling vertical position.

In flaccid laryngeal paralysis, the vocal process (VP) is displaced laterally and superiorly. The arytenoid adduction procedure (AA) moves the VP medially and caudally, closing the glottic gap. However, clinical evidence suggests that the VP is more caudal after AA than in physiological phonation. The neurally intact arytenoid is supported by tonic and phonatory activity of the posterior cricoarytenoid muscle (PCA). We hypothesize that a posterior anchoring suture could replace PCA support, achieving a more natural VP location. Cadaver larynges were scanned with computed tomography at rest and after AA, alone or in combination with a second arytenoid suture anchored to either the posterior midline cricoid (PC) or the inferior thyroid cornu (IC). Each posterior suture reduced caudal displacement of the VP during AA, but the glottic gap was wider with the PC suture. In 3 patients undergoing AA for laryngeal paralysis, the IC suture improved arytenoid posture and voice quality.

The role of the posterior cricoarytenoid muscle in phonation: An electromyographic investigation in dogs

The activity of the posterior cricoarytenoid muscle during respiration has been well investigated electromyographically. Its activity during phonation, however, has not been studied systematically. We, therefore, focused our attention on the phonatory activity of the posterior cricoarytenoid muscle to confirm whether it also contracts during phonation, as has been reported by some researchers. In our series of 12 adult dogs, the posterior cricoarytenoid was active in 11 dogs and inactive in one dog during phonation. Our present study also showed that the posterior cricoarytenoid activity was stronger for phonation than for inspiration in 6, stronger for inspiration than for phonation in 3, and the same for phonation and inspiration in 2 dogs. The results obtained from the present electromyographic evaluation demonstrated that the posterior cricoarytenoid is activated during phonation. The authors believe that the posterior cricoarytenoid muscle has phonatory function and that the phonatory effect of this muscle on the vocal cord may play an important role in precise glottis control.

Neuroanatomical model for laryngeal operation

<h2>Summary</h2> The focus of this presentation is on the development of a neuroanatomical model underlying laryngeal function. It is suggested that the model can be used as an aid to the understanding of the structures that support phonatory output as well as a basis for physiological research on the nature of voice production. Although the postulates are anatomically grounded, the approach utilized also shows that there is ongoing feedback during phonation and, hence, that both the motor and sensory (neural) networks are coordinated during any phonatory activity. Additionally, the discussion serves to review the neuroanatomical interface between respiration and voice.

Cricothyroid muscle in respiration.

Although the phonatory activity of cricothyroid muscle is well-known, its respiratory role often remains unrecognized. Recent data suggest this muscle plays a major role in the overall regulation of breathing by its control of expiratory resistance and flow. Cricothyroid contraction in expiration results in vocal elongation increasing glottic size. Such a mechanical effect reduces airway resistance and shortens expiratory duration. By such a mechanism, the rate of respiration may ultimately be modified using the larynx as the principal effector of this control. In this regard, cricothyroid expiratory activity is a pressure-sensitive evoked response influenced by afferent vagal stimuli. Its activity is triggered by a critical threshold of pressure-increase with respect to time, and its duration is directly dependent on the duration of positive subglottic pressure. The threshold of cricothyroid activation is reduced in hypercapnia and elevated in hypocapnic states.

Changes in Subglottal Air Pressure Associated with Changes of Fundamental Frequency

Subglottal air pressure was recorded with the aid of an intratracheal catheter as three young adult males produced an upward and downward glissando. From a graphic display of both the pressure and the phonation, changes in pressure (ΔPs) and fundamental frequency (Δfo) were determined. The mean Δfo/ΔPs ratio for both phonatory activities was 7.67 semitones per centimeter of water. This is considerably larger than reported by previous investigators. Moreover, when only the range of fundamentals most often used for speech was considered an even larger ratio was found. Even though the importance of subglottal pressure to the generation of a laryngeal tone cannot be denied, the present data suggest that changes in the fundamental of that tone are probably more directly related to laryngeal adjustments such as changes in mass and length of the vocal folds.