Exam 3: L5 Audition

Question 1

Auditory System:

Sound waves travel on superimposed air

range is ____ to ___ Hz (human voice range is)

intensity of sound is related to ____ of oscillations

Answer 1

Auditory System:
sound waves travel on superimposed air

range is 15 Hz - 20KHz (human voice is between 1 and 5 KHz)

Intensity of sound is related to amplitude of oscillations

Question 2

Functional overview:
Explain what the following do

Outer ear

middle ear

inner ear

Answer 2

Outer ear: collection

middle ear: amplification

inner ear: transduction

Remember, we hear our own voice differently because it travels through bone and not just air

Question 3

Function:
Collection: the _____ protects, funnels sound, and performs spectral filtering for sound localization

Amplification & Conduction: the ______ ear acts as impedence device, allows for adequate transfer of energy from air to fluid filled cochlea, amplifying it for detection

Transduction: the _____ ear is the sensory transducer of the ear

Answer 3

Function:
Collection: the outer ear protects, funnels sound, and performs spectral filtering for sound localization

Amplification & Conduction: the middle ear acts as impedence device, allows for adequate transfer of energy from air to fluid filled cochlea, amplifying it for detection

Transduction: the inner ear is the sensory transducer of the ear

Question 4

Function of Middle Ear Ossicles:

There is a significant energy loss when sound travels from a gas to a liquid due to ______

Answer 4

Function of middle ear ossicles:

There is a significant energy loss when sound travels from a gas to a liquid due to impedence mismatch

Question 5

Sound waves enter your ear, they vibrate the ____ membrane, and then vibrate the ossicles

ossicles in order: _____, _____, then ____
The _____ then stomps on the oval window to send the signal to the inner ear

Answer 5

Sound waves enter your ear, they vibrate the tympanic window, then vibrate the ossicles

malleus, incus, then stapes

Stapes is tiny bone that stomps on oval window to displace lymph and send signals to inner ear

Question 6

Middle ear structures

Name the ossicles

Then explain which one is the hammer, anvil, and stirrup

Answer 6

Middle ear structures: AMPLIFICATION

Ossicles:

Malleus (hammer)

Incus (anvil)

Stapes (stirrup)

Question 7

Middle Ear Muscles: stapedius and tensor tympani

contraction of the middle ear muscles (stapedius and tensor tympani) causes ______ amplification for _____ against loud noises

Answer 7

Contraction of middle ear muscles (stapedius and tensor tympani) causes DECREASED amplification for protection against loud noises

Question 8

Acoustic Stapedius Reflex

Question 9

Cochlea:

Consists of three fluid filled chambers:

1.

2.

3.

Answer 9

Cochlea:

consists of three fluid filled chambers

1. scala vestibuli

(resinner’s membrane)

2. cochlear duct

(basular membrane)

3. scala tympani

Question 10

Fluids of the Inner Ear:

Perilymph: very similar to _____ fluid, high ___ and ___ and low protein

Endolymph: contains high ___, low ___ and ___

+80 mV

Answer 10

Question 11

Sound Transduction:

Pressure vibrations in the cochlea induce movement

vibration of the _______ (site of mechano-electrical transduction)

Answer 11

Pressure vibration in cochlea induce movement

vibration of the organ of Corti (site of mechano-electrical transduction)