SLH 358 - The Vocal Folds and Phonatory System

What is the difference between the true and false vocal folds?

The true vocal folds have muscular control and can make contact to allow for voicing or to act as a valve. Typically, the false folds have no muscular control and cannot make contact.

What is the ventricle of Morgagni?

It is the space between the false and real vocal folds.

Where are the false vocal folds found?

Above the true vocal folds but below the epiglottis.

The vocalis muscle is found…

inside the vocal folds.

What is considered part of the supraglottal region?

The area above the vocal folds.

What is considered part of the glottal region?

The area encompassing the vocal folds.

What is considered part of the subglottal region.

The area below the vocal folds.

How many layers does the vocal fold have?

Five.

What is the epithelium layer of the VF?

The outer most layer of the vocal folds which is made of a mucus membrane.

What is the superficial layer of the VF?

It is the second layer from the surface of the vocal folds, made of a gelatinous tissue.

What is intermediate layer of the VF?

It is the third layer from the surface of the vocal folds, made of an elastic tissue.

What is the deep layer of the VF?

The fourth layer from the surface of the VF. This layer is a connective tissue that has movement, but is not considered elastic.

What is the vocalis muscle?

The innermost layer of the vocal folds.

The vocal ligament is composed of the…

Intermediate layer and deep layer of the VF.

The Lamia Propria is composed of the…

superficial, intermediate, and deep layers of the vocal folds.

The average female thyroid cartilage has a…

broader thyroid angle.

The broader thyroid angel found in females causes…

a posterior glottal gap (chink) between the adducted vocal folds.

This posterior glottal gap (chink) leads to…

breathiness during normal phonation.

Abduction and adduction is the opening and closing of the glottis by..

active muscular force.

Vocal fold vibration is the result of opening and closing the adducted vocal folds by…

aero dynamic and myoelastic forces.

When quiet breathing, the vocal folds are…

completely abducted.

When whispering (making noise/glottal frication-aspiration), the vocal folds are…

partially adducted.

When voicing (including breathy, normal, and creaky voice) the vocal folds are…

over adducting.

When cutting off voicing to create silence like a glottal stop, your vocal folds are…

fully adducted with no air pressure pushing through.

The cycle of VF vibration allows the air flow and subglottal pressure to…

blow the adducted vocal folds apart.

The cycle of VF vibration involves the elastic recoil forces and Bernoulli effect to…

bring the VF back together.

At the beginning of a phonation cycle, the VF are adducted and subglottal pressure…

begins to build up.

During the second part of the phonation cycle, the subglottal pressure that built…

begins to deform the inferior surface of the VF as pressure continues to build.

During the third part of the phonation cycle, the mass of high-pressure air begins to develop…

modulations as it is affect by the motion of the mucosa.

During the fourth part of the phonation cycle, the complex wave of compressed subglottal air…

breaks free and begins to emerge from between the VF, creating a glottal pulse.

In the fifth part of the phonation cycle, aerodynamic and elastic recoil forces begin to…

bring the VFs back together via the Bernoulli effect.

Pre-phonation phase is the

period during which the vocal folds move from an abducted position to an adducted position.

During the pre-phonation phase what things occur?

The vocal folds become adducted, controlled exhalation occurs, subglottal pressure builds up below the adducted vocal folds.

The attack phase is the

period during which the vocal folds undergo regular cycles of aerodynamic and myoelastic vibration.

During the attack phase, what things occur?

Vocal folds are adducted, controlled exhalation occurs. Subglottal pressure deforms the vocal folds from below. When subglottal pressure forces vocal folds apart, a burst of compressed air is released (glottal pulse). Bernoulli effect sucks the folds back together, elastic recoil forces operate to return the folds to a non-deformed position.

Medial compression is the…

activity of the muscles that control adduction and also help contribute to the amount of tension in the VFs.

Which muscles adduct the vocal folds and squeezes them together?

The lateral cricoarytenoids, transverse and oblique arytenoids, and muscularis.

What determines whether a voice will be breathy, normal, or creaky?

amount of adduction.

There is a direct relationship between the amount of medial compression and the

amount of air pressure needed to initiate phonation.

Longitudinal Tension where the muscles that control stretching and tensing forces are applied to the

vocal folds which change the pitch of the voice.

Which muscles heightens the pitch by making the vocal folds longer, more tense overall, and have less mass per unit of length?

The cricothyroids.

Which muscles lower the pitch by making the vocal folds more tense internally, more flaccid at the vibrating edge, shorter, and have more mass per unit of length?

The vocalis.

Which two sets of muscles must be involved in order to control and change pitch?

The cricothyroid and vocalis.

What is the fundamental frequency of phonation (F0)?

The number of cycles of phonation per second (hertz) that the vocal folds produce when they are vibrating.

Thicker, more flaccid folds vibrate more…

slowly.

Thinner more tense folds vibrate…

quickly.

Mass per unit of length must be decreased by a factor of ___ in order to double the frequency of vibration (cricothyroid action).

four.

The posterior cricoarytenoids does when when we try to increase pitch?

They anchor the arytenoid cartilages during the cricothyroid action with assistance from the suprahyoid muscles.

Habitual pitch is usually close to the…

lower limits of an individual’s pitch range.

To lower pitch, the vocalis must contract and the lateral cricoarytenoid may help by providing…

needed medial compression to maintain adduction. Extrinsic laryngeal muscles (strap muscles) are also active.

The intensity of phonation is a function of the amount of…

subglottal pressure being produced by controlled exhalation during speech breathing.

Higher intensity is perceived as a…

louder sound.

Lower intensity is perceived as a …

softer sound.

The sound intensity level of the voice will increase by how many decibels when subglottal pressure is doubled?

8-12 dB

Speakers can vary in intensity by as much as…

70 dB.

As pitch rises, subglottal pressure must too because…

the more tense vocal folds offer greater resistance to air pressure.

Speakers can produce a larger dynamic range of intensity at the…

mid-range of pitch.

What is an endoscope?

A narrow device with a camera and a light that can be inserted down the throat to take pictures of the laryngeal function.

What is a stroboscope?

A type of endoscope with a strobing light which appears to slow down motion so the viewer can observe phonation.

What is translumination?

A procedure in which a light sensor placed on the neck near the glottis. This technique measures the light source that shine through the glottis during abduction and phonation.