Straw Phonation Research Articles

Vocal Fold Vibration Characteristics during SOVTE using a Vibration Simulator and Digital Kymography

Objectives: The purpose of this study is to investigate the characteristics of vocal fold vibration during sustained vowel /a/ phonation and various semi-occluded vocal tract exercise (SOVTEs) using a vibration simulator and digital kymography (DKG).Methods: A total of 12 normal young speakers (6 males, 6 females) aged 20-30 years participated in the study. They phonated a sustained /a/ vowel and performed SOVTE. The vocal fold vibration characteristics were measured according to the number of vibration sources (single vs. double), and vocal tract occlusion degree using a vibration simulator and DKG. Glottal gap quotient (GQ, %), speed quotient (SQ, %) and amplitude (pixel) were estimated quantitatively from the DKG image.Results: The results showed that significantly higher GQ (p = .000) and SQ (p = .000) were observed in the humming and bilabial fricative /β/ compared to open vowels. The amplitude was significantly higher in the open vowel /a/ than in humming (p = .018) and bilabial fricative /β/ (p = .003). Also, when comparing the vocal fold vibration parameters according to vibration type (single source: straw phonation vs. double source: straw phonation with water), the double source presented a significantly higher GQ (p = .000) as well as SQ (p = .008) in comparison with a single source.Conclusion: SOVTE showed a glottal gap that is different from the opened vowel /a/. It also had a longer opening of the vocal fold and a smaller amplitude than the vowel. This suggests that SOVTE may be helpful for facilitating vocal fold vibration and good voice quality in clinical practice. The current study can be meaningful in providing theoretical and clinical evidence for SOVTE.

Immediate and Short-term Effects of Straw Phonation in Air or Water on Vocal Fold Vibration and Supraglottic Activity of Adult Patients with Voice Disorders Visualized with Strobovideolaryngoscopy: A Pilot Study

Purpose The first purpose of this study was to investigate and compare the short-term effects after a semi-occluded vocal tract (SOVT) therapy session consisting of straw phonation (SP) in air or water on vocal fold vibration and supraglottic activity of adult patients with voice disorders, visualized with strobovideolaryngoscopy (SVL). The second purpose of this study was to investigate and compare immediate changes in the patients' vocal fold vibration and supraglottic activity during SP in air or water, visualized with SVL. Methods Twelve adult patients with voice disorders (eight women and four men, mean age 52 years) were assigned randomly to one of two study groups: SP in air or SP in water. Immediately before and after a therapy session of 15 min, participants underwent a rigid SVL to determine the short-term effects of the SP session. At the posttherapy examination, flexible SVL while performing SP was added to determine the effects occurring during SP. The visual-perceptual ratings were performed blindly and in random order by three laryngologists, using the Voice-Vibratory Assessment with Laryngeal Imaging rating form for stroboscopy. ResultsShort-term effects after SP: After the SP-in-air session, the supraglottic mediolateral compression decreased significantly. The SP-in-water session led to significantly increased left vibrational amplitude. Immediate effects during SP: During SP in air, a significantly increased left amplitude and mucosal wave, and significantly decreased mediolateral supraglottic activity, were found. SP in water tended to decrease the vibrational amplitude during performance of the task. A trend toward higher anteroposterior supraglottic compression was observed during both SP in air and water, being more prominent in the latter. Conclusion SP in air led to less false vocal fold adduction and consequently less hyperfunction. The small increment in anteroposterior supraglottic activity during SP in air and water might be related to epilarynx narrowing, an economic phenomenon associated with SOVT exercises. The effects on vibrational amplitude were rather ambiguous. The small reduction in amplitude during SP in water is expected to diminish vocal fold impact stress and therefore creates an ideal basis for voice therapy. The increment in amplitude and mucosal wave during SP in air might indicate insufficient supraglottic pressure to obtain the favorable effects of semi-occlusion. Whether or not the rise in amplitude after the SP-in-water session is due to voice efficiency or voice fatigue remains unknown. Future larger-scale investigation in subgroups of voice patients is needed to explore these hypotheses.

Immediate Effects of Semi-occluded Vocal Tract Exercises as a Vocal Warm-Up in Singers

The present study aimed to investigate the Immediate Effects of Semi-occluded Vocal Tract Exercises (SOVTEs) as a vocal warm-up on the Electrical Activity of Extrinsic Laryngeal Muscles and acoustic parameters of voice in singers. This study used a pre-/post-interventional (quasi-experimental) design and a simple non-random sampling method. Musculoskeletal Rehabilitation Research Center. Surface electromyography of the suprahyoid and infrahyoid muscle areas and acoustic measurements were assessed before and immediately after performing three SOVTEs: lip-trill, humming, and straw phonation for 20 minutes as a vocal warm-up in eleven healthy male singers with an average age of 26.5 ± 4.2. After performing the vocal warm-up, root mean square in channels two and three (left and right infrahyoid muscle areas) in all vocal tasks, including /i/, /u/, and counting from 20 to 30 was significantly decreased (P < 0.05). The acoustic parameters, F1, and F1-F0 difference were significantly decreased (P < 0.05). The results suggest that after performing SOVTEs as a vocal warm-up, the electrical activity of the extrinsic laryngeal muscles is reduced. The acoustic analysis also demonstrated a decrease in F0, F1, and F1-F0 variables. Therefore, it seems that the results of acoustic and electromyographic assessments are in line and it is likely that SOVTEs through the vocal economy lead to a reduction in the load applied to the phonatory system.

Restoration Strategies Following Short-Term Vocal Exertion in Healthy Young Adults.

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.

Using a Lossy Electrical Transmission Line Model for Optimizing Straw Phonation Configurations

Straw phonation has a long history of being a successful vocal therapy technique. However, not much is known about the mechanics of phonation with a straw, nor the best combination of phoneme and straw dimensions to be used. A significant limitation in research thus far is the complexity of existing models and computation techniques to determine acoustic and aerodynamic values such as impedance. In this study, a new electrical circuit-based model of the vocal tract as a transmission line is evaluated and compared to established impedance calculation methods. Results indicate that the model is not complete yet, so several adjustments are suggested and discussed. In addition, straw phonation configurations are examined using previously developed models to determine which maximize impedance and power.

Remotely collecting immediate voice production effects of semi-occluded vocal tract exercises

The purpose of this study was to evaluate the feasibility of remote collection of immediate vocal production effects of semi-occluded vocal tract exercises (SOVTs). Participants received a shipment of study equipment and materials with instructions on how to set-up and configure them. The collection protocol was conducted with remote guidance from the researcher via a Zoom session. The protocol included a double baseline voice recording, experimental tasks consisting of straw phonation and straw phonation into a cup of water, and a post-task recording. Audio recordings of sustained vowels, CAPE-V sentences, and the Rainbow Passage were analyzed for jitter, shimmer, harmonic-to-noise ratio, cepstral peak prominence, and presence of a singer’s formant. Following the tasks, participants were asked to provide self-perceptual ratings of vocal quality and vocal effort. Auditory-perceptual analysis (CAPE-V) was also performed, in which expert listeners (speech-language pathologists with extensive voice backgrounds) rated differences following the SOVT tasks. Instrumentation and methodology will be discussed, with a focus on the strengths and weaknesses of remote data collection including which voice assessment metrics were still robust to immediate SOVT effects, even in a remote setting. While obtaining lab-quality audio recordings for acoustic analysis remotely is considered challenging, this study suggests that it is feasible to obtain high-quality data remotely.

Vocal and self-perception effects of straw phonation exercises

ABSTRACT Purpose: to assess the acoustic and self-perceived voice changes in women with and without voice symptoms after 1, 3, 5, and 7 minutes of straw phonation exercises. Methods: a total of 30 women aged 18 to 39 years participated in the study - 17 with and 13 without voice symptoms. The participants filled in the visual analog scale on self-perceived voice discomfort. The sustained vowel /ɛ/ was recorded in maximum phonation time before (m0) and after the first, third, fifth, and seventh minute performing straw phonation exercises. The maximum phonation time was measured, and an acoustic analysis was made, encompassing the following parameters: the number of harmonics, fundamental frequency, noise, glottal-to-noise excitation ratio (GNE), jitter, and shimmer. The Friedman and Wilcoxon tests were used to compare each parameter at the different moments, and the Mann-Whitney test, to compare the groups. The 5% significance level was set for the analyses. Results: no changes were found in either the acoustic variables or the self-perception of voice comparing the moments before and after the exercises in either group. The comparison between the groups revealed that the one with voice symptoms had lower GNE and higher noise values at the second moment performing the technique. Conclusion: the straw phonation did not cause acoustic or self-perceived voice changes in women with and without voice symptoms. The comparison between the groups showed that the women with symptoms had lower GNE and higher noise values than those without symptoms, after 1 minute performing straw phonation.

Immediate Effects of Straw Phonation in Water Exercises on Parameters of Vocal Loading in Carnatic Classical Singers

The present study aimed to investigate the effect of vocal loading and the immediate effects of straw phonation in water exercises on parameters of vocal loading in Carnatic classical singers. A within-subject pretest-posttest design. Twelve healthy Carnatic classical singers participated in the vocal loading experiment for 2 days, referred to as no-treatment and treatment conditions. The vocal loading task consisted of 1 hour of continuous singing in the presence of background noise. For the treatment condition, the participants followed a 10-minute straw phonation in water exercises before the vocal loading task. Acoustic, electroglottographic, and self-rated perceptual voice measures were recorded before and after the vocal loading task on both days. Pretest and posttest comparison of various outcome measures during no-treatment day suggested a significant increase in shimmer percent, decrease in maximum phonation duration of vowel /a/, and increase in perceived phonatory effort, perceived vocal effort, and Evaluation of Ability to Sing Easily scores. Pretest and posttest comparisons during treatment day showed a significant increase in Mean F0, Highest F0, and Lowest F0, perceived phonatory effort, and perceived vocal effort scores. However, changes in Mean F0, Highest F0, and Lowest F0 measures were small in the posttest condition compared to pretest. The present results suggest that vocal loading did induce changes in Carnatic classical singers' voices. However, there is no substantial evidence that straw phonation is effective in reducing the vocal loading in Carnatic classical singers. Further studies are required to corroborate the current findings.

Can Straw Phonation Be Considered As Vocal Warm Up Among Speech Language Pathologists?

Straw phonation exercises have been proved to be effective in improving voice quality among persons with voice pathology. The aim of the study was to investigate the effects of straw phonation as a warm-up exercise on maximum phonation duration, acoustic, and perceptual parameters of voice among Speech Language Pathologists. The study adopted a pretest-posttest design. Twenty-five females with the mean age range of 20.87 ± 1.15 years participated in the study and completed a series of straw phonation exercises for three cycles. Maximum phonation duration, acoustic, and self-perceptual measures were assessed before and after the straw phonation exercises. F0, jitter, shimmer, nose to harmonic ratio, intensity, F1, F2, F3, F4, Maximum phonation duration, and the post self-perceptual measures were analyzed. The results indicated a significant improvement in the F0, intensity, F1, F2, F4, Maximum phonation duration, and self-perceptual measures. Straw phonation exercises provides an easy and effective warm up technique to improve the voice quality among Speech Language Pathologists and can be considered before conducting therapy sessions.

Efficacy of different straw phonation doses for vocal fatigue prevention

Purpose The aim of the present study was to investigate the efficacy of different straw phonation doses for vocal fatigue (VF) prevention. Method Thirteen males and 13 females participated in the study. Each participant received seven preventive treatments (i.e. voice rest with hydration for 15 minutes, straw phonation into air or water for one, three and five minutes) in separate visits. Phonatory threshold pressure (PTP) and self-perceived vocal fatigue (PVF) symptoms severity were adopted as the primary and secondary outcome measures, respectively. Measurements were taken before and after the preventive treatment, and after a 90-minute VF-inducing task. Result PTP was maintained in four of the straw phonation doses, namely; the one-minute into air, one-minute, three-minute and five-minute into water conditions; but not in the voice rest condition. Straw phonation into water of a depth of 5 cm for one minute was considered the optimal dose for VF prevention. PVF, however, was not maintained after VF-inducing task in all treatment conditions. Conclusion Straw phonation into water for one minute was capable of preventing phonatory efficiency (as measured with PTP) from deteriorating. The dose identified in the present study may be adopted for future prevention studies in population that is vulnerable to VF.

Effects of Varied Semi-Occluded Vocal Tract Exercises on Acoustic and Perceptual Measures of Music Theatre Singers: A Pilot Study

ABSTRACT Recent investigations of semi-occluded vocal tract exercises (SOVTEs) have indicated possible benefits for voice therapy and for choral and classical singing. Few researchers have investigated SOVTEs with contemporary commercial music (CCM) singers. The current study examined perceptual and acoustic effects of five sung conditions:/m/, lip trill, drinking straw phonation (6 mm diameter), stirring straw phonation (2.5 mm diameter), and unoccluded/a/(control). Six participants sang a music theatre solo excerpt prior to and after using one of the SOVTEs, which were randomized with the control condition over five days. Acoustic analyses of the final note and singer self reports of vocal effort provided data for analysis. Results indicated some trends toward improvements in acoustic measures of the SOVTEs compared to the/a/condition, though no particular exercise emerged as most effective. Singers reported potential benefits for all the exercises, with stirring straw rated as having the lowest posttest effort and lip trill rated as having the most robust across-the-board effect. Other results were largely idiosyncratic. These results suggest there may be benefits for SOVTEs in music theatre singing, but it may take some sleuthing for voice teachers to help each student discover which exercise is most individually beneficial.

Nasal Resistance (NR) Technique: A Novel Approach to Improve Glottal Adduction

Several techniques have been practiced in the field of voice therapy to balance glottal pressures and improve glottal adduction. As such, Semioccluded Vocal Tract Exercises using narrow diameter straws have shown promise as a technique to increase glottal contact as reflected by Closed Quotients (CQ) measured from electroglottograph (EGG). This study explored the effect of nasal resistance (NR) technique, a manually induced NR approach, on glottal adduction in phononormal subjects as a possible new therapeutic technique to assist in glottal closure. Thirty-four vocally healthy adult females qualified for this study. All subjects were reportedly and perceptually normal. Subjects were instructed to perform tasks including (a) steady modal phonation, (b) straw phonation, (c) humming, and (d) NR technique in a random order. EGG measures included calculation of the CQ and jitter during the mid-section of each stimuli for a minimum of 10 EGG cycles. One-way repeated measures ANOVAs and Bonferroni post-hoc comparisons were calculated to determine differences between each phonatory task for the outcome measures of CQ and jitter. Analyses revealed that the mean CQ was significantly different in all the tasks performed with humming (33.99%) at the lowest and NR technique at highest (43.88%). Though the CQ of straw phonation (40.53%) was higher than modal steady phonation (36.65%), jitter was found to be significantly lower for NR technique (0.23%). Jitter during straw phonation (0.43%) did not differ significantly from modal phonation (0.44%). These results provide preliminary evidence that NR technique can increase CQ with lower levels of jitter compared to straw phonation using a narrow diameter of 2 mm. Future studies should expand enrollment to men, larger age ranges, and patients with hypofunctional symptoms (eg, Parkinson disease) to evaluate the potential benefits of NR as a therapeutic technique.

Effects of a 6-Week Straw Phonation in Water Exercise Program on the Aging Voice.

Purpose Semi-occluded vocal tract (SOVT) exercises with tubes or straws have been widely used for a variety of voice disorders. Yet, the effects of longer periods of SOVT exercises (lasting for weeks) on the aging voice are not well understood. This study investigated the effects of a 6-week straw phonation in water (SPW) exercise program. Method Thirty-seven elderly subjects with self-perceived voice problems were assigned into two groups: (a) SPW exercises with six weekly sessions and home practice (experimental group) and (b) vocal hygiene education (control group). Before and after intervention (2 weeks after the completion of the exercise program), acoustic analysis, auditory-perceptual evaluation, and self-assessment of vocal impairment were conducted. Results Analysis of covariance revealed significant differences between the two groups in smoothed cepstral peak prominence measures, harmonics-to-noise ratio, the auditory-perceptual parameter of breathiness, and Voice Handicap Index-10 scores postintervention. No significant differences between the two groups were found for other measures. Conclusions Our results supported the positive effects of SOVT exercises for the aging voice, with a 6-week SPW exercise program being a clinical option. Future studies should involve long-term follow-up and additional outcome measures to better understand the efficacy of SOVT exercises, particularly SPW exercises, for the aging voice.

The Therapeutic Effects of Straw Phonation on Vocal Fatigue.

Straw phonation has been investigated for its vocal warm-up effects on healthy populations and therapeutic effects on voice patients. The purpose of this article was to determine whether it is beneficial for vocal fatigue. Prospective cohort study METHODS: Twenty-five healthy participants were recruited into 1-hour vocal loading tasks followed by 10-minute vocal rest or straw phonation on 2 different days. Various parameters including phonation threshold pressure (PTP), mean airflow, closed quotient (CQ), current speaking effort level (EFFT), and laryngeal discomfort (DISC) were acquired at baseline, after vocal load, and after the intervention. Increased PTP, EFFT, and DISC were observed after vocal load. Decreased PTP, EFFT, and DISC were then acquired after both vocal rest or straw phonation. More significant improvements were obtained in straw phonation when compared with vocal rest. Additionally, significantly increased mean flow and decreased CQ were obtained after straw phonation when compared to vocal rest. Straw phonation has the potential to adjust aerodynamics within the vocal tract leading to improved vocal efficiency, optimized vibration mode, and attenuated vocal fatigue. This study provided a promising treatment for vocal fatigue that could have wide clinical relevance to voice users with high voice demands. 4 Laryngoscope, 130:E674-E679, 2020.

Effects of Varying Lengths and Diameters During Straw Phonation on an Excised Canine Model

Straw phonation, a well-established method of vocal exercise, started over 100 years ago. However, some of the most basic questions about best practices remain including the ideal extension length and the ideal restriction (semiocclusion) diameter. This study aims to help answer these questions by looking at both separately, with all other variables controlled. Four (4) straws with lengths of 5, 25, 50, and 75 centimeters and 4 restrictions with diameters of 3, 9, 15, and 21 mm were tested, separately. They were attached to the end of a simulated vocal tract which was then affixed to an excised canine larynx. Airflow was increased until the larynges achieved self-sustained phonation then aerodynamic, acoustic, and electroglottographic data were collected. There was a significant decrease in the phonation threshold pressure using the 5 and 25 cm straw lengths and the 9 and 15 mm restrictions. The phonation threshold flow and contact quotient saw insignificant changes, except in the case of the 3 mm restriction. It is theorized that the increased inertive reactance helps to decrease phonation threshold pressure. By controlling for all other variables, the effects of the length or diameter of the straw can be analyzed in isolation. These results narrow the significant range of lengths and diameters used in straw phonation.

Effects of a simulated system of straw phonation on the complete phonatory range of excised canine larynges.

This study investigated the effects of straw phonation therapy on the aerodynamic and acoustic parameters of the vocal folds at different levels of elongation and subglottal pressure. 20 excised canine larynges were used in both experimental (straw phonation therapy simulation) and control conditions. Aerodynamic parameters, including phonation threshold pressure (PTP), phonation instability pressure (PIP), phonation pressure range (PPR), phonation threshold flow (PTF), phonation instability flow (PIF), phonation flow range (PFR), were obtained at different levels of vocal fold elongation (0%, 10%, 20%). Acoustic parameters, including fundamental frequency (F0), jitter, shimmer, signal noise ratio (SNR) were detected at different levels of vocal fold elongation (0%, 10%, 20%) and subglottal pressure (15 cmH2O, 20 cmH2O, 25 cmH2O). Significant decreases in PTP and PTF and significant increases in PIP, PIF, PPR, and PFR occurred in experimental condition at all levels of elongation when compared with control condition. However, no significant changes of acoustic parameters were obtained between conditions at all levels. At different levels of vocal fold elongation, straw phonation not only lowered the onset of normal voice, but also elevated the onset of chaotic voice, indicating a better voice economy and voice control. Moreover, the improved phonatory range demonstrated that straw phonation had the potential to prevent voice users who have high voice demand from voice fatigue and vocal damage.

Effects of Straw Phonation and Neutral Vowel Protocols on the Choral Sound of Two Matched Women’s Choirs

Many choral teacher-conductors and voice professionals utilize semioccluded vocal tract (SOVT) exercises (e.g., lip trills, straw phonation) in their classrooms or studios. Research with individual singers has indicated that these techniques may increase “vocal economy,” boosting acoustic output while reducing singer effort. Recently, researchers have investigated these phenomena in choral settings, finding that choirs have maintained or increased spectral energy after straw phonation. Most chorister participants have perceived improved choral sound and vocal efficiency after the protocols. These investigations, however, have used one-group pretest-posttest designs. Therefore, results could reflect a “masterclass effect.” The purpose of this study was to compare acoustic output and listener perceptions of pre- and posttest measurements of two matched women’s choirs who engaged in (a) a straw phonation protocol or (b) an identical protocol performed on a neutral, unoccluded vowel (“ah”). Results indicated that both groups sang with more spectral energy after the protocols, and a majority of expert listeners noted these increases. However, the straw group’s increase was more than 1 dB SPL greater across the entire spectrum (0–10 kHz). Choral teacher-conductors and music teacher educators may wish to use straw phonation exercises to increase choral output and reduce vocal effort.

Effects of Straw Phonation on Acoustic and Perceptual Measures of a Barbershop Chorus

Abstract Voice instructors, speech language pathologists, and choral directors frequently utilize semi-occluded vocal tract (SOVT) exercises in their practices. These exercises, which narrow the vocal tract above the vocal folds, have been found to reduce voicing effort while maintaining or boosting acoustic output of individual speakers and singers. Recent investigations of choirs have aligned, with choirs maintaining or increasing acoustic output after a straw phonation protocol and, in one study, singer perceptions of improved choral sound and vocal efficiency. These choral studies have taken place with traditional Western Classical-style ensembles. SOVT exercises, however, are also frequently recommended in groups that sing in other styles (e.g., barbershop), in which thousands of school and community choristers participate. Though each style may involve unique vocal techniques, no published study to date has investigated the efficacy of SOVT protocols in non-Western Classical choral ensembles. Therefore, the purpose of this study was to measure the effect of a group straw phonation protocol on acoustic and perceptual changes of conglomerate, choral sound in a male barbershop chorus. Results indicated that the group sang with 1.00 dB SPL increased spectral energy (0–10 kHz) after the straw protocol, possibly indicating a “just noticeable” difference. Most singer participants also thought the group sounded better (85.7%) and that they individually sang more efficiently (62.5%) after the protocols. These results align with previous research and may indicate that choral teacher-conductors and music teacher educators in barbershop settings could utilize SOVT exercises to improve “vocal economy” by increasing vocal output with reduced effort.

Lingering Effects of Straw Phonation Exercises on Aerodynamic, Electroglottographic, and Acoustic Parameters

This study aimed to investigate the duration of straw phonation effects using aerodynamic, electroglottographic, and acoustic metrics. Twenty-four participants were recruited to perform both a 5-minute and a 10-minute straw phonation exercise. Upon completion of the exercises, phonation threshold pressure (PTP), mean airflow, contact quotient, fundamental frequency, jitter, shimmer, and noise-to-harmonics ratio were measured over a 20-minute time frame. Parameters were measured before the intervention (baseline), immediately after the intervention (m0), 5 minutes (m5), 10 minutes (m10), 15 minutes (m15), and 20 minutes (m20) after the intervention. PTP significantly decreased immediately after 5 minutes of straw phonation and returned to initial state within 5 minutes. PTP remained decreased over 5 minutes after 10 minutes of straw phonation. Mean airflow increased immediately after both 5 minutes and 10 minutes of straw phonations and remained improved for 20 minutes. No significant changes were obtained for contact quotient and acoustic parameters over the intervention period. The results extended our knowledge of proper clinical application of straw phonation regarding the duration of exercise. This study confirmed that 10 minutes of straw phonation lead to optimal and relatively continuous effects in PTP and mean airflow. Although straw phonation did show lingering effects in aerodynamics, repeated practices were recommended to obtain optimum and therapeutic effects.

Effects of a straw phonation protocol on acoustic and perceptual measures of choirs

Voice instructors, choral directors, and voice professionals have long utilized semi-occluded vocal tract (SOVT) exercises to evoke efficient voicing from their students or clients. These exercises, which involve narrowing and/or lengthening the vocal tract as a means of increasing pharyngeal pressure, can include nasal consonants, lip or tongue trills, raspberries, or vocalizing through a tube or straw. Researchers have noted that the increased pressure reduces the amount of breath pressure required to initiate voicing (i.e., phonation threshold pressure) while maintaining or increasing acoustic output (e.g., sound pressure level, formant intensity). The result may be increased “vocal economy” or “vocal efficiency” (i.e., increased vocal output with decreased effort). Until recently, however, this research was limited to effects on individuals. This paper includes a series of studies in which choirs of varied voicing (SATB, SSAA, and TTBB) sang unaccompanied pieces prior to and after performing voicing exercises through a small stirring straw. Long-term average spectra have indicated that most choirs maintained or increased acoustic output in the conglomerate, choral sound after the protocols. Singers have also perceived improved choral sound and decreased singing effort. These results may interest choral directors who wish to improve the vocal economy of their ensembles.