Outer Ear

Question 1

What are the 2 main functional purposes of the pinna?

Answer 1

Sound collection/localization

Protective mechanism

Question 2

What are the major audiological consequences of pinna damage?

Answer 2

The major audiological consequence of pinna damage is the inability to localize sound. The pinna provides spectral shape cues that contribute to elevation and back versus front sound source information. There also could be a slight change in the resonant frequency of the outer ear. The pinna has a resonant frequency of approximately 4,000 Hz. If there is pinna damage, and/or loss, that can result in changes in the cumulative resonant frequency of the outer ear.

Question 3

The ear canal in children is roughly what direction? In adults?

Answer 3

Adults: ear canal is roughly perpendicular but slightly downward at end

Children: ear canal is more perpendicular

Question 4

What is the general shape of the ear canal? What is shaped like this?

Answer 4

2 curves, lazy-S

Question 5

What portion of the ear canal is surrounded by cartilage? Bone?

Answer 5

1st third is cartilage

Other two-thirds are bone

Question 6

Cerumen is produced in what part of the ear canal?

Answer 6

Outer 1/3 of meatus

Question 7

What is the function of cerumen?

Answer 7

Protects the ear from foreign bodies, like bugs.

Question 8

The ear canal primarily acts like what kind of resonator?

Answer 8

Open-closed pipe

Question 9

At what frequency is the primary resonance of the ear canal and meatus?

Answer 9

2.5 kHz

Question 10

What parts of the body contribute to the resonances by the time one reaches the tympanic membrane?

Answer 10

Head
Torso and neck
Concha
Pinna flange
Ear canal and eardrum