Laryngeal and Vocal Fold Physiology

Question 1

Name some primary biological functions of the VFs

Answer 1

regulate airflow in and out of respiratory tract

protective-close when we swallow

species-specific vocalizations

Question 2

Why do VF tissues change dynamically?

Answer 2

to adjust pitch and loudness of vocalizations

Question 3

What kind of structure are the VFs?

Answer 3

LAYERED

Question 4

VF epithelium

Answer 4

anchored to the remainder of fold

Question 5

Which layer of the Lamina Propria vibrates a lot?

Answer 5

superficial

Question 6

What kind of fibers is the superficial layer of the Lamina Propria made of mostly?

Answer 6

elastic fibers

Question 7

What kind of fibers is the deep layer of the Lamina Propria made of?

Answer 7

collagenous fibers

Question 8

What kind of fibers is the intermediate layer of the Lamina Propria made of?

Answer 8

elastic, BUT is less flexible and more dense than the superficial layer

Question 9

VF is also made up of which muscle?

Answer 9

the TA

Question 10

Cover of VF

Answer 10

epithelium and superficial layer of lamina propria

Question 11

Transitional Zone of VF

Answer 11

intermediate and deep lamina propria

Question 12

Body of VF

Answer 12

the muscle-TA

Question 13

Differences between cover, transitional zones, and body

Answer 13

cover and transitional zones are passively regulated while the body can be actively regulated

Question 14

Medial Compression

Answer 14

forces that act to approximate the VFs at midline

-combo of LCA and IA to rotate the arytenoid cartilages

Question 15

Longitudinal Tension

Answer 15

• stretching forces applied to VF tissue

- use of CT, TA, and extrinsic mm’s

Question 16

What is the relationship between compression forces and the phonatory threshold?

Answer 16

higher compression forces translate into a higher phonatory threshold for vibration initiation

-more compression, higher phonatory threshold

Question 17

Pitch changes MAY result from..

Answer 17

changes in length and tension of VFs

Question 18

What happens when the VFs increase in length?

Answer 18

increase in length of the overall VF by itself decreases thickness of VF which can function to elevate pitch if operating alone

Question 19

Increase in TENSION is more important for pitch elevation. Tension increases dramatically because..

Answer 19

changes in eleastic nature of VF tissue when it is lengthened due to antagonistic contraction of TA and CT

Question 20

What is pitch?

Answer 20

relates to the frequency of VF vibration

Question 21

Frequency

Answer 21

is an objective measure of a physical phenomenon

-rate at which an object vibrates and is measure in Hz

Question 22

Describe the contraction of CT alone

Answer 22

stretches vocal ligaments and VF tissue

does not significantly increase pitch

Question 23

Describe TA contraction alone

Answer 23

only acts to shorten the VFs and decrease the distance between the thyroid and arytenoid

Question 24

What happens when these actions occur simultaneously?

Answer 24

effective longitudinal tension builds

Question 25

Why does PCA activity increase slightly during pitch shifts?

Answer 25

may function to prevent a forward movement of the arytenoid cartilage when the CT contract and pulls TA thinner

may act to anchor the arytenoid from the strain of tension also

Question 26

What happens when these actions occur simultaneously?

Answer 26

effective longitudinal tension builds

Question 27

Why does PCA activity increase slightly during pitch shifts?

Answer 27

may function to prevent a forward movement of the arytenoid cartilage when the CT contract and pulls TA thinner

may act to anchor the arytenoid from the strain of tension also

Question 28

Name some primary biological functions of the VFs

Answer 28

regulate airflow in and out of respiratory tract

protective-close when we swallow

species-specific vocalizations

Question 29

Pitch lowering is primarily achieved by what?

Answer 29

changes in TA activity

Question 30

How does the TA lower pitch?

Answer 30

• reduction in distance between thyroid and arytenoids

- vocal ligament becomes relaxed as a consequence

Question 31

In general, intensity is regulated by..

Answer 31

the degree of medial compression in the glottis and greater respiratory drive

Question 32

What does more medial compression result in?

Answer 32

greater levels of resistance to air flow, thus producing an increase in Psg