Chapter 5 Phonation

The Bernoulli effect has a critical role in vocal fold:

Adduction

The medial, adductory, movement of the vocal folds is sometimes referred to as:

Approximation

Daniell Bernoulli was a contemporary of:

Benjamin Franklin (1706-1790)

The cricoarytenoid joints play a role in opening and closing the vocal folds. What two important function does thins opening and closing facilitiate?

Breathing and Phonation

What kind of glottal shape is lika a pyramid, with the upper margin of the vocal folds forming the apex of the pyramid and the lower margin and conus elasticus forming the wider base?

Convergent

Which joins allow the arytenoid cartilages to rock anteriorly, posteriorly, medially , and laterally, enabling the vocal folds to adduct and abduct?

Cricoarytenoid joints

What is the Bernoulli effect?

Daniel Bernoulli is a Swiss physicist who determined that Newton's 2nd Law of Motion (force is equal to mass times acceleration) applied to atoms and molecule. If the number of air molecules is doubled, the rate of collision between the molecules and the container walls must double as well. Similary, decrease the number of air molecules by one-half, and the rate of collisions will be half, leading to a halving of the air pressure.

What vocal folds are often used in research on vocal fold physiology because of their similarity to human vocal folds?

Dog

Define elasticity and tension.

Elasticity is the ability of an object to spring back to its resting shape when deforming forces are removed. Tensions refers to the stiffness or the degree to which an object resists being deformed.

What is another name for transglottal pressure?

Explain why it got this name. Transglottal pressuer is also called the driving pressure in that this difference in the air pressures is the driving force that sets the vocal folds into vibration.

Elongation of the vocal folds plays a critical role in the tension on the vocal folds, which regulate fundamental:

Frequency

What is the event that results in acoustic excitation of the air in the vocal tract?

Glottal closure

Discuss a major weakness of the myoelastic -aerodynamic theory as it was initially proposed.

Hussen propose that neural input, not aerodynamic forces caused the muscles of the vocal folds to pulsate which then modified the airstream to produce the sound wave.

Increasing the tension of the vocal folds causes the rate of vibration to:

Increase

The frequency at which a string vibrates depends up 3 factors. Name the 3, and explain about each what makes the sound produced higher or lower in frequency.

Intensity, density, and length. Long strings vibrates slower which produces lower sound. Short strings vibrates faster producing higher tones. In summary, the shorter the string, or the smaller the mass or the greater the tension the higher the fundamental frequency. Men have longer, thicker vocal folds, therefore the vibration is slower, the pitch will be low.

In 1958, who published a detailed explanation of the 1843 theory, "postulating that the vocal folds are actuated by the stream of air delivered by the lungs and trachea?

Janwillem van den Berg

In 1843, who first proposed the myoelastic -aerodynamic theory of voice production, a theory that forms the basis of our current understanding of how voice is produced?

Johannes Muller

What is the internal force that results in a change in the volume or shape of a material after the material has been subjected to external force?

Kinetic energy

What serve as a variable impediment to the airflow?

Lungs

The major theory of voice production is call the _____________________.

Myoelastic-aerodynamic theory.

A plot of the stress strain properties of vocal folds tissue would be:

Nonlinear

Ex vivo stretching of the animal thyroarytenoid muscle means that the stretching is done:

Out of the living body

Describe the difference between static and dynamic fluids.

Static fluids are conditions in which are at rest in stable or equilibrium; Still fluid. Dynamic fluids are the studies of fluids in motion; Moving fluid.

What is the force divided by the cross-sectional area perpendicular to the direction of the force?

Stress

What is the essence of the myoelastic-aerodynamic theory?

The basis of this theory is that the elasticity of the vocal folds allows them be set into vibration by aerodynameic forces

Discuss two differnent schemata for organizing the histologic layers of the vocal folds in to biomechanical functional units.

The control of f and intensity requires variable stiffness of the biomechanical layers of the vocal folds. Changes in stiffness are obtained actively and passively. Passive changes can be understood by using the stress-strain plot. STRESS is the force of divided by the cross-sectional area perpendicular to the direction of the force. In other words, stress is a measure of the internal distribution of force per unit area within a material. It is the internal force that results in the change in the volume or shape of a material after the material has be subjected to external forces. Stress tends to displace (move) the materials. STRAIN is the length of the change of the tissue in the direction of the foce divided by the resting length. That is, when the vocal folds are stretched long or contracted short, the force acting up them is call STRAIN.

During inspiration the vocal folds move outward slightly, and during exhalation the move inward slightly. Explain the results of these movement.

The outward movement serves to widen the lumen (opening) of the airway to decrease resistance to the airflow and ease inhalation. Slight medial movement of the vocal fold during exhalation increases resistance to the airflow and my help to slow the rate of airflow and increase gaseous exchange at the level of the alveoli.

Strictly speaking, the glottis is:

The space between the vocal folds

With regard to the stress-strain curve, discuss the differences, if any between the upward slope as a muscle is stretched and the downward slope as the muscle is released and allowed to contract to resting length.

The upward slope of the curve upon stretch is different from the downward slope of the curve as the muscle is released and allowed to contract back to resting length. As the Muscle is stretched to 20% of its resting length (20% strain), the stress built up in the muscle is little over 5kPA, yet as the muscle is being relaxed and decreases to 20% strain, the stress within the muscle is approximately 2kPA.

Three features of the closure of the vocal folds are particularly important in the regulation of speech intensity. Name the 3, and discuss how each affect intensity.

Vocal closure- 3 features: duration, speed, the degree of closure 1 Duration: duration of the closed phases increases with greater intensity, which permits an increase in the lung pressure level. 2 Speed: the faster the vocal folds close the shaper the cutoff of the air flowing through the glottis, the more energy is transmitted to the air mass above the vocal folds. 3 Degree of Closure: Incomplete closure can limit the buildup of lungpressure, and it can allow loss of acoustic energy in the subglottal direction.

The opening of the vocal folds is called __________

abduction

What stress is the air pressure within the glottis during the open phase of phonation called?

aerodynamic

The presentation of something other than air to the larynx stimulates a/an:

cough

The paired joints of the larynx who movements allow the vocal folds to be elongated, are called the _____________.

cricothyroid joints.

The paired joints are responsible for adduction and adduction of the vocal folds are called the _______________________.

cricroarytenoid joints.

The muscles that adjust and stylized the overall position of the larynx in the neck are, are a group, referred to as the ________________________.

extrinsic muscles

The histologic layers of the vocal folds may also be represented by a ________ schema.

functional

Fluid flows from:

greater pressure to lesser pressure

A sustained Valsalva maneuver temporarily impedes blood flow to the:

heart

The tissue layers of the vocal folds covering the muscle are the superior, intermediate, and deep layers of the _____________.

lamina propria

What is the major regulatory of vocal intensity?

lung pressure

A factor that contributes to the increase in frequency of the vocal folds is the change in:

mass per unit length

The prefix myo-means:

muscle

The distinct biomechanical properties of the different layers of the vocal folds allow for changes in:

pitch and loudness

The valving action of the larynx has three function, stabilization of the upper body,___________________________________

protect the lungs from foreign body, and breathing.

All humans tissues, compared with the strings of a musical instrument are :

slightly more stiff

The airway above the vocal tract is referred to as the ____________________.

supraglottis

What stress is the greater force per unit of area of the vocal folds?

tensile

When we refer to active and passive stress characteristics of the vocal folds, wer restrict our discussion to:

the vocal folds themselves

In general, only what vibrates during soft and high frequency phonation?

vocal fold cover

The intrinsic laryngeal muscles receive the innervation from Cranial Nerve ____ called the ____________________.

x: vagus

Lung pressure during speech typically ranges between:

.3 and 1.2kPa

The valving action of the larynx function to stabilize the upper body during certain action. Name 3 or 4 of these actions.

1 lifting heavy objects 2 Running up a flight of stairs 3 Pushing when defecating

Basic Function of the larynx

1-to keep foreign objects from getting into the lungs. 2-to help with phonation and swallowing 3-to stabilize the upper body for lifting, running, defecating

The initiation of phonation, referred to as the onset of phonation, is often divided into what 3 type? Name and define each of the three.

1. Simultaneous (gentle) onset- referred to as soft onset, phonation is intiated by simultaneously exhalation and adduction of the vocal folds at midline 2. Breathy onset- called aspirate onset, the exhalation and airflow through the glottis in initiated before the vocal folds are adducted. The amount of air released before onset of phonation can be quite variable ranging form minimal to significant air wastage. 3. Glottal Attack - called hard onset of phonation, the vocal folds are firmly approximated prior to initiating phonation. Hard onset involves significant medial compression of the vocal folds, allowing a buildup of lung pressure. When the vocal folds are released, the vocal folds are blown apart in an "explosive nature".

If no attempt is made to control f0 with activation of the thyroarytenoid or the cricothyroid muscle, and f0 is allowed to very freely, research shows that an increase of approximately how many HZ per KPa can be achieved?

20-40

Up to how may kPa is typical for loud speech?

3.0kPa

49. The larynx consist of _____ paired and _____unpaired cartilages.

3:3

The forward gliding motion of the thyroid cartilage upon contraction of the pars oblique of the cricothyroid muscle may be responsible for up to what percentage of the potiential elongation of the vocal folds?

75-85%