Chapter 59: The Professional Voice

Question 1

Sound generation requires (3)

and corresponding part of the body

Answer 1

1: Power source - Lungs
2. Vibrator - Larynx
3. Resonator - Supraglottal vocal tract (supraglottic larynx, pharynx, oral cavity and potentially nasal cavity)

Question 2

Type of epithelium covering the vocal fold:

Answer 2

stratified squamous

Question 3

Layers of the lamina propria and contents/structure

Answer 3

1. Superficial Layer: Fibroblasts
2. Intermediate Layer: elastin fibers
3. Deep Layer: collagen

I - E
D - C

Question 4

Other term for Superficial Layer or Lamina Propria:

Answer 4

Reinke Space

Question 5

BODY - COVER Theory.
Cover: ____
Transition Zone: ____
Body: ____

Answer 5

Cover: Epithelium + Superficial Layer of Lamina Propria

Transition Zone: Intermediate and Deep Layer of Lamina Propria (Vocal Ligament)

Body: Thyroarytenoid muscle

Question 6

Principle behind Body - Cover Theory:

Answer 6

The contrasting masses
and physical properties of the vocal fold cover and body cause
them to move at different rates as air passes between the vocal folds. This movement, or vibration, creates sound at the level
of the vocal folds by disturbing the local pressure equilibrium
within the area of the glottis.

Question 7

Types of collagen fibers in lamina propria:

Answer 7

Collagen type III and VII

Question 8

Concept in formation of vocal fold lesions related to the basement membrane.

Answer 8

contents of the
basement membrane zone and the lamina propria. The basement
membrane zone is a complex area that anchors the epidermis
to the superficial layer of the lamina propria (Fig. 59-3).
It is the site of tremendous shearing forces in the human vocal
fold that occur during vocal fold vibration. Excessive shear
forces can lead to disruption of the basement membrane zone
and to the development of infiltrates in this area,6 a process
important in the formation of vocal fold lesion

Question 9

Mechanism of Voice Production:

Answer 9

Vocalization begins with air, or the power supply: the lungs
supply the essential energy for sound production by presenting
the larynx (oscillator) with a stream of air. The diaphragm; the
intercostal, back, and abdominal musculature; and the elastic
recoil of the chest wall work in concert during inspiration and
expiration to control the release of air.12,13 Classically trained
singers use the abdominal and thoracic musculature to regulate
exhalation; they tend to use a greater percentage of total lung
capacity than non–classically trained singers to produce sound
in a more efficient manner.14,15 This enhanced efficiency of air
propulsion to the larynx is a key difference between trained
and untrained voice users.
As the diaphragm relaxes, and the chest wall recoils to a
resting state, air is pushed through the nearly closed vocal folds.
Because the air passage at the glottal level is smaller than the
air passage of the trachea and subglottis, pressure in the region
of the glottis drops as the velocity of the air column increases.
The relative vacuum created by this drop in pressure draws the
pliable rima glottal tissues of the membranous vocal fold region
together, a phenomenon known as the Bernoulli effect. After
closure at the membranous vocal fold at the glottal level, the
air column from the lungs and trachea continues to flow into
the subglottal region. The rising subglottal air pressure forces
the vocal folds back open. The vocal folds, or rima glottal
tissues, open from inferiorly to superiorly (inferior to superior
lip) to form an alternating convergent and divergent glottal
configuration. The aerodynamic forces of the air column and
the inherent myoelastic properties of the vocal folds, particularly
in the region of the vocal fold cover, are responsible for
the repeated opening and closing of the rima glottal tissues that
pulses the air column as it flows out of the glottis. These disruptions
in the steady state of the tracheal air pressure by glottal
activity result in sound production.

Question 10

Methods by which subglottal pressure can be altered: (2)

Answer 10

1. to modify the force of the
   expelled air from the trachea. This is accomplished through
   activation of the abdominal and thoracic musculature to
   increase the amount of air inspired and then, partially through
   elastic recoil properties of the thoracic cavity and partially
   through voluntary muscular activity, to control the rate of air
   egress.
2. to modify the
   force of vocal fold adduction. This method is somewhat less
   efficient. Increasing the force of laryngeal closure through
   activity of the thyroarytenoid, lateral cricoarytenoid, and interarytenoid muscles achieves greater resistance to the glottal
   opening; this in turn raises subglottal pressure, which increases
   sound intensity.

Question 11

Activation of the cricothyroid produces this action on the VOCAL FOLD and subsequently on the COVER and VIBRATION.

Answer 11

elongates the vocal fold

thus

tensing the cover

and

elevating the frequency of vibration