semi-occluded vocal tract exercises for voice therapy (and singing) aka – why we trill, hum, use...

Semi-Occluded Vocal Tract Exercises for Voice Therapy (and singing)AKA –

Why we Trill, Hum, use straws etc.

Liz Savina, Redcliffe HospitalFor Qld Voice Special Interest Group

May 2014

Overview

Definition & brief background of physics What major therapy “programs” use it Discuss some recent studies that show the

effects of different parameters/ on different populations.

Demonstrations Therapy hierarchies Case examples

3 Major Ways of Doing SOVT (Andrade 2014)

1. Constant frontal narrowing of the vocal tract (nasals/glides and hand-over-mouth);

2. Lengthening (and narrowing) the vocal tract through means of a tube (Lax-Vox/Straw).

3. Adding a 2ndry source of vibration into the vocal tract (lip and tongue-trills, Tube into water/fricatives).

• Been used in various forms for over 100 years (Conroy et al. 2014)

My burning questions

• Is it guaranteed to work??• Which types are best for

– building up vocalis (muscle within vocal cords) and closing glottic gaps versus

– Improving retraction/deconstriction, preventing overclosure

Why/How Does SOVT Work?

Potentially decreases the aerodynamic power necessary for phonation & optimises closure of the vocal folds – neither breathy or pressed (Andrade et al. 2014)

An entire conference on SOVT!

A little bit of the physicsSOVT (at the lips) works by…….- Raising the mean supraglottal and intraglottal pressures- Impedance matching by vocal fold adduction and epilarynx

tube narrowing can then make the voice more efficient and more economical (in terms of tissue collision).(Titze 2006)

Decrease in phonation threshold pressure Reduced minimum pressure at which the VC will vibrate

– Decreased phonatory effort

– Decreased strain

(Conroy et al 2014, Guzman et al., 2013),

The vocal fold adduction appears to be a reflex reaction.

A little bit of physicsLowering of the first vocal tract formant (F1) allowing the fundamental frequency (F0) of speech to be closer to F1, Increasing inertive reactance of the vocal tract and producing a more efficient vocal fold vibration pattern -> easier voicing

http://www2.psychology.uiowa.edu/faculty/mcmurray/speechglossary/

Some SOVT• Widen the pharynx in relation to the epilarynx -

> a clustering of the 3rd, 4th, & 5th formants (Andrade 2014) – “Singer’s Formant”

Marco Guzman, et al Resonance Tube and Straw Phonation 523.e27

SOVT is used in

Stemple’s Vocal Function Exercises (nasals & Finnish bilabial fricative)

Verdolini-Abbots – LMRVT – core part of her Voice Therapy Spectrum – using M

LaxVox (9mm id, 25cm (Andrade) or 35 cm (Stemple) tube in 1-5cm of water (aim for 3-5cm - Stemple)

Finnish Resonance Tube (soft silicone or glass tube 25-27 cm & 9 mm id in 2-5cm of water or free air) ~40 year hx (Paes)

SOVT is used in• Accent Method (voiced fricatives)• Estill Siren on “ng”, sirening• Titze’s Straw exercise (small diameter

for men, larger diameter for women – Titze Brisbane 2013)

• Glide loaded sentence of CAPE-V – We were away a year ago

& S/Z ratio

Lax Vox – Stemple 20111 of the Big 3 things for future

voice therapy.

Lax Vox indicated for:Stemple (2011)

Holistic therapy for various functional and organic voice disorders:Muscle tension dysphoniaVocal fold nodules and polypsHabitual and psychogenic dysphonias-aphonias

(by masking proprioceptive feedback) Vocal fold paralysis (RLN and SLN)PresbyphoniaPuberphonia• Pre and postoperative phonosurgery

Lax Vox in Singing and Theatre voice Stemple (2011)

Daily voice care for all groups of voice users Prevention of voice problems for vocal athletes Developing vocal muscles with several exercises

(glissando, staccato, Messa di Voce, etc.) Glottal closure deficiencies Warming up and cooling down Finding and developing the optimal voice (primal sound) Balancing the glottal attack Facilitating the lowered larynx Developing registers and smoothing the passaggio

Lax Vox ReferenceDenizoglu I, SihvoM. Lax Vox Voice Therapy Technique. CurrPractORL 2010, 6(2):284-295 (unable to find on Medline Ovid or Ebsco or Pubmed or even Google!)

SOVT researched in:

• Teachers (RVT and Finnish Tube)• Elderly (Finnish Tube)• Actors and singers (RVT)• “Behavioural” voice problems• Benign vocal lesions• Haven’t yet found research on Unilateral Vocal

Fold Paralysis

Some Recent Studies

http://fraukruse.wordpress.com/2013/03/07/lax-vox-voice-therapy/

Some Recent Studies

• Immediate effects – normal speakers– trained/untrained instructed/non-instructed– dyshphonic/ hyperfunctional populations (tubes)

• Effect of 6 week programme on “elderly” (tube in water)

• 24 Hours of RV

http://fraukruse.wordpress.com/2013/03/07/lax-vox-voice-therapy/

Summary of Articles will follow

Andrade et al 2014 Electroglottographic Study of Seven Semi-Occluded

Exercises:…….Journal of Voice

Andrade 2014 SOVTE

1. LaxVox (9mm id, 25cm –? Water depth)2. Straw (12.5 cm in length & 4 mm in

diameter)

3. Lip-trill4. Tongue-trill5. Hand-over-mouth6. Humming 7. Tongue-trill with hand-over-mouth.

Procedure Andrade 2014

N = 23 healthy volunteers SP demonstrated and provided teaching on

error until subjects produced correctly Asked to do same pitch for all activities.

Electroglottographic & Acoustic measures

F1 – F0 Andrade 2014

Steady (single source) • Hand-over-mouth• Humming • Strawwith lower CQr & F1 - F0 differenceEasiest Phonation

Fluctuating (dual source) • Tongue-trill• Lip-trill• LaxVoxwith larger CQr & F1 - F0 differenceMore effortful phonation but ? gives massage effect

SOVTAndrade et al. 2014

Massaging the Vocal Tract

Note the bouncing of the pharyngeal walls – easier to see in the second half of clip when the pitch is held constant.

Tongue Trill + Hand Over Mouth Andrade 2014

Exhibited mixed effects in both the exercise groups

Costa et al., 2011. Immediate effects of the phonation into a straw exercise

Costa et al 2011 N = 48, 23 with benign lesions (nodules, cysts,

polyps, and Reinke’s edema ), 25 without. Rigid plastic straw 8.7 cm long & 1.5 mm diam Examiner demonstrated then participants did 1

minute of straw phonation at self selected mid range frequency and intensity.

Videolaryngoscopy, vocal self Ax, acoustic and auditory perception Ax

Costa et al 2011

• Significant improvement on vocal self Ax in patients with benign vocal lesions (p=0. 015) but no change in patients without lesions.

• No statistically significant differences before and after the exercise and between the groups, in the videolaryngoscopy, acoustic and auditory-perception assessments

Gaskill, C. S., & Quinney, D. M. (2012). The effect of resonance tubes on glottal contact quotient with and without task instruction: a

comparison of trained and untrained voices. Journal of Voice

Gaskill & Quinney 2012

Two groups of male participants, 10 with no vocal training 10 with classical vocal training,

No instruction/practice: told keep pitch and loudness consistent

Instruction/practice: got to practice until found best pitch and loudness and had sense of oral resonance

Gaskill & Quinney 2012 Procedure

12 reps of a vowel-like phonation for at least 5 seconds.

Narrow glass tube, 8 mm ID and 50 cm Some participants needed to be cued to

not produce a humming or nasalized sound, but to allow all of the sound to go through the tube instead of coming through the nose.

Gaskill & Quinney 2012 Conclusions Resonance tube can cause immediate and

measurable changes in glottal CQ These changes remain highly variable and

do not always fit with theoretical predictions

does need an individualized approach that could include trying multiple tube lengths and diameters as well as extended and systematic practice with larger variations in pitch than those exhibited in this study

Guzman et al 2013 Laryngeal and Pharyngeal Activity During Semioccluded Vocal Tract Postures in Subjects Diagnosed

With Hyperfunctional Dysphonia

8 SOVT exercises:

SOVT postures Guzman et al 2013

N=20 hyperfunctional dysphonia 8 SOVT exercises: Blinded laryngologists rated 3 endoscopic

variables using a five-point Likert scalevertical laryngeal position (VLP), pharyngeal

constriction, and laryngeal compression

SOVT postures in hyperfunctional dysphonia Guzman et al 2013

All semioccluded techniques produced a lower larynx narrower aryepiglottic opening and a wider pharynx Compared to resting position

VLP, A-P constriction,& pharyngeal width changed differently throughout the 8 semi-occluded postures.

Most prominent changes were obtained with a tube into the water and narrow tube into the air

Lower Laryngeal Position

Straw exercises: Before (left), during (middle), after (right)Findings:

Lower laryngeal position both during and afterHigher velum position both during and afterHypopharynx much wider during

(Different Guzman et al., 2013, pg 523.e24 Figure 6)

Paes, et al. (2013). Immediate effects of the Finnish resonance tube method on behavioral dysphonia. J Voice, 27(6), 717-722. doi: 10.1016/j.jvoice.2013.04.007

Paes 2012

• 25 female teachers minimum 5-year history of dysphonia & no prior speech therapy.

• Subjects produced 3 sets of 10 sustained phonations with a 1-minute rest between phonations

27-cm glass tube immersed in at least/up to 2 cm of water. 

Results – Paes 2012

• 68% of the teachers reported increased phonatory comfort

• 52% reported improved voice quality after performing the exercises.

• Perceptual analysis: improved voice on counting numbers but not on “ah”

• Spectrogram: decreased instability, subharmonics, noise in high frequencies, and the tendency for reduced low frequency noise on.

• Mean fundamental frequency decreased.

Dos Santos, et. al.(2014). Verifying the effectiveness of using resonance tubes in voice therapy with elderly

people.

Resonance Tubes in the “Elderly”Dos Santos et al 2014

Resonance Tube Group: Improvement in Grade, Asthenia, Strain,

Instability on GRBASI No change in breathiness 90% self-reported improvement Improved Vital Capacity Improved spirometry

Resonance Tubes in the “Elderly”Dos Santos et al 2014

N= 42 elderly in long term care residential between ages of 62-93 years

30 females x6 1 hour weekly sessions of resonance tube, compared to

vocal hygiene ed sessions. Glass tubes (8 mm to 9 mm ID and 24 cm to 25 cm length

in 2-5cm of water). RT Therapy Rx: instructed to emit continuous sounds,

nonsensical words, and to hum the tune of “Happy Birthday to You.”

Rest periods of up to two minutes between emissions.

Verdolini, 2012. Vocal exercise may attenuate acute vocal fold inflammation

Resonant voice for treatment of vocal fold inflammation Verdolini 2012

N=3 healthy males Used Resonant Voice Prospective, Randomized and double blind 1-hour vocal loading procedure, followed by

randomization to aTalking as normal condition, Vocal rest condition, RV

exercise condition Treatments were monitored in clinic for 4 hours

and continued extra-clinically until the next morning.

Resonant voice for treatment of vocal fold inflammation Verdolini 2012

Results• Complete data sets were obtained for 3 inflammatory biomarkers--IL-1beta, IL-6, MMP-8 Results were poorest at 24-hour follow-up in

the talking as normal condition Sharply improved in the voice rest condition Were the best in the RV condition

Summary

• SOVT exercises can optimise the closure of the vocal folds, open the pharynx wider

• These effects tend to occur immediately• They are not guaranteed to do so, so still need to be

individually checked – person doing should feel a more “open throat”, less effortful voicing and sound should improve( that’s up to our subjective judgement)

• If SOVT improves the vocal tract configuration, evidence shows this can then be carried over to vowels and other speech sounds.