Phonation Flashcards
Larynx
The Voice-box
Complex organ in the anterior neck
Cartilage, muscle, fat, connective tissue, bone
Works in concert with lungs & oral/nasal cavities to produce voice
Functions of Respiratory System
Respiration (breathing)
Provision of airway
Protection of airway
Deglutation (swallowing)
Closure of larynx
Cessation of breathing
Phonation (voice)
Vibrating airstream and elements
Laryngeal Muscles
Intrinsic (inside larynx)
Abduction (opening)
Adduction (closing)
Tension
Extrinsic (outside larynx)
Position of larynx in neck
Infrahyoid (below)
Suprahyoid (above)
Resonator
Above vocal folds
Supraglottic vocal tract
Oscillator
Vocal folds
Elastic, pliability properties
Power Source
Below vocal folds
Infraglottic vocal tract
Phonation
Rapid (vibratory) opening/closing of vocal folds
Interrupts stream of air
Series of air puffs
Rippling displacement of vocal fold cover
(Mucosal wave)
Produces a vocal tone
Myoelastic aerodynamic theory
Bernoulli Effect
When a gas flows through a constricted passage, the velocity increases
Inward pressure is > the outward pressure
Walls are drawn into each other
Controls the closing of VF
Myoelastic Aerodynamic Theory
Drives the vibratory cycle of the vocal folds
The myoelastic theory states that when the vocal cords are brought together and breath pressure is applied to them, the cords remain closed until the pressure beneath them—the subglottic pressure—is sufficient to push them apart, allowing air to escape and reducing the pressure enough for the muscle tension recoil to pull the folds back together again. Pressure builds up once again until the cords are pushed apart, and the whole cycle keeps repeating itself. The rate at which the cords open and close—the number of cycles per second—determines the pitch of the phonation.
Voicing
Each vibration of the VF allows a brief puff of air to escape producing an audible sound at the frequency of the opening.
Vocal Sound Production Process
Diaphragm action pushes air from the lungs through the vocal folds, producing a periodic train of air pulses.
This pulse train is shaped by the resonances of the vocal tract.
The basic resonances, called vocal formants, can be changed by the action of the articulators to produce distinguishable voice sounds, like the vowel sounds.
VF Vibratory Process
Subglottic air pressure builds up to separate the folds
The sudden drop in pressure pulls the cords together
Air rushes through the glottis at increased velocity
As the top of the folds are opening, the bottom of the folds is closing
This creates a wavelike motion (mucosal wave)
Fundamental Frequency
The number of times the vocal folds are blown apart and come together per second
Directly related to the length, mass and tension of the vocal folds
The repetition rate of a complex periodic wave
When speaking or singing there is always an underlying note to each sound
Pitch is defined as the average rate of vocal fold vibration and is measured in cycles per second or Hertz
For pitch to rise, the VF must vibrate more quickly. They get thinner by being stretched longer.
Pitch
Equal to Frequency: Number of cycles per second, Measured in hertz (Hz)
Fundamental frequency (F0)
Male: 100-150 Hz
Female: 180-250 Hz
(“middle C” on piano scale = 256Hz; octave higher = 512Hz)
Generally increases as vocal folds are thinned and stretched and pressure increases
Intensity of the Voice
Intensity (loudness) is the size of the sound wave
Increasing subglottal air pressure increases vocal intensity
Increased vocal intensity results from greater resistance by the vocal folds to the increased airflow
The folds don’t open any further than usual, but they stay closed longer, creating more distinct “puffs of air”
The VF are pressed together more firmly
Articulation affects the potential pressure difference
Voice Therapy
Changing vocal behaviors in order to achieve improved vocal function
Identifying vocally abusive behaviors
Implementing a vocal hygiene program
Respiration training
Relaxation exercises
Refocusing vocal tone
Addressing pitch, loudness, and rate
Reducing forceful initiation of speech
Hoarseness
There is almost ALWAYS more than one thing going on in the larynx.
The cause of hoarseness is often multi-factorial.
Treatment may be multi-tiered and include medication, voice therapy, surgery.
Therapy Goal: Assist each patient in achieving his or her best possible voice
Vocal Misuses
Speaking in noisy situations
Excessive talking
Telephone use with the handset cradled to the shoulder
Using inappropriate pitch when speaking
Not using amplification when publicly speaking
Using the voice in a hard/harsh manner – forced whisper
Voice Care
Drink plenty of fluids, especially water (64 oz/day)
Stimulate secretions with gum, lozenges, warm drinks
Use a humidifier
Maintain good nutrition with a healthy, well-balanced diet
Check medications for adverse side effects on the mouth or throat
Alcohol, caffeine and tobacco have adverse effects on your voice
Be alert to reflux problems
Voice Tips
Try not to scream or yell
Warm up your voice before heavy use
Don’t smoke
Use good breath support
Use a microphone
Listen to your voice
Limit dairy products
Preventing Reflux
Avoid drinking alcohol, citrus-type juices and carbonated beverages
Avoid reclining for 3 hours after meals
Avoid eating immediately before bedtime
Avoid exercising, singing within 3 hours of eating
Elevate the head of your bed 4 to 6 inches
Avoid overeating
Avoid caffeine, chocolate, peppermint, fat
If overweight, losing weight is helpful
Medications the Affect Voice
Ace inhibitors – may induce a cough or throat clearing
Oral contraceptions- may cause fluid retention in the vocal cords
Testosterone – deepen the voice
Anticoagulants – may increase changes of vocal cord hemorrhage
Herbal medications – are not harmless and should be take with caution
Allergy Medication - can dry out the folds
Voice Don’ts
Don’t clear your throat or cough frequently
Don’t yell or scream
Don’t talk across long distances
Don’t speak or lecture without using a microphone
Don’t talk very much with laryngitis
Don’t laugh or cry out loud aggressively for extended periods
Don’t yell or speak extensively during strenuous physical exercise
Don’t talk beyond the natural breath cycle
Don’t tense the upper body and throat to inhale
Don’t sing beyond comfortable pitch and loudness range
Don’t make unconventional sounds for prolonged periods
Don’t clench your teeth and hold your face tense
Don’t strain when talking
Voice Do’s
Do substitute swallowing water or saliva
Do substitute clapping whistling, ringing a bell, blowing a horn
Do adjust the environment to reduce background noise
Do keep your voice relaxed and let the microphone amplify your voice
Do rest your voice like the rest of your body.
Do speak in low-volume, easy and relaxed voice. Be aware of the effect stress and emotion have on your voice
Do be aware of the effects of physical exertion on your voice
Do breath deeply from your diaphragm. Pause often, and replace breath
Do relax neck and jaw muscles, breathing from the diaphragm
Do allow registers to change as pitch rises and drops
Do allow the jaw to relax and “float” as you speak
Do pay attention to soreness or tightness in the throat. Do use a soft-voice tone.
Do organize your day to include voice rest periods. Use an effortless voice and use yawns, sighs, and hums to relax your voice.
