(Cochlear Function)

Question 1

chain of events that occur from middle ear to auditory nerve

Answer 1

traveling wave in cochlear duct > basilar membrane displaces > hair cells shear > cili of hair cells bend > chemical release/mechanical release/cochlear microphonic > action potential > to auditory nerve

Question 2

There’s a _ force and _ of the _ that cause _ innervating the hair cell to _.

Answer 2

There’s a SHEARING force and BONDING of the CILIA that cause NERVE FIBERS innervating the hair cell to FIRE.

Question 3

Hair cell stereocilia bundles and OHC & IHC bundles demonstrate these 3 properties needed for the cochlear amplifier

Answer 3

Frequency selectivity, provide amplification, have a force generating component (p 498 Katz)

Question 4

What contributes to the production of OAEs? (Their contributions may be stimulus level dependent)

Answer 4

OHC somatic motility and stereocilia

Question 5

Reflection or “___” emissions are characterized by___that rotates rapidly with changes in stimulus frequency

Answer 5

“Place-fixed“, phase

Question 6

Neurons that receive information from our sensory organs (e.g. eye, skin) and transmit this input to the central nervous system are called

Answer 6

Afferent neurons

Question 7

Neurons that send impulses from the central nervous system to your limbs and organs are called

Answer 7

Efferent neurons

Question 8

__ pathways carry signals away from the central nervous system

Answer 8

Efferent

Question 9

This pathway carries signals that your brain sends to tell your body to do something, like blinking

Answer 9

Efferent pathway

Question 10

These signals come from outside stimuli and tell your brain what they are sensing, such as temperature.

Answer 10

Afferent signals

Question 11

Neurons that receive information from our sensory organs (e.g. eye, skin) and transmit this input to the central nervous system are called

Answer 11

Afferent neurons

Question 12

The term sensory/neural is actually a broad one because it suggests that hearing loss is

Answer 12

either sensory (in the inner ear) or neural (on the auditory nerve), although it may, of course, be both.

Question 13

The inner ear is a

Answer 13

fluid-filled space, interfaced between the middle ear and the
auditory nerve.

Question 14

The cochlear portion of the inner ear acts as a device to

Answer 14

convert sound into a form of electrochemical energy that transmits info to the brain about the frequency, intensity, and phase of sound waves.

Question 15

When the basilar membrane within the cochlea moves up and down in response to __ caused by the rocking movement of the __ in the __, the hair cells within the __ are __ stimulating the __.

Answer 15

When the basilar membrane within the cochlea moves up and down in response to fluid displacement caused by the rocking movement of the stapes in the oval window, the hair cells within the organ of Corti are sheared stimulating the auditory nerve.

Question 16

There are more than three times as many __ than __

Answer 16

There are more than three times as many outer hair cells than inner hair cells.

Question 17

outer hair cells assist the inner hair cells in detect-ing __ __ __ and __ the __ of the __ __ along the __ __ for __ __ __ allowing for __ __ of __.

Answer 17

These outer hair cells assist the inner hair cells in detecting softer input sounds and sharpen the peak of the traveling wave along the basilar membrane for enhanced frequency specificity allowing for better perception of speech.

Question 18

What is the function of the ampullae?

Answer 18

The ampullae contain the cristae, which are the end organs of the semicircular canals.

Question 19

What is the function of the organ of Corti?

Answer 19

OCC is the end organ for hearing and transduces the mechanical energy in the middle ear to an electrochemical code to be transmitted to the brain.

Question 20

What can be done to treat autoimmune inner-ear disease?

Answer 20

A Numbers of drugs have been tried, including steroids.

Question 21

How do hair cells stimulate the auditory nerve?

Answer 21

The hair cells located in the OOC transduce mechanical sound vibrations into nerve impulses. They are stimulated when the BM vibrates.

Question 22

Retrocochlear hearing loss occurs

Answer 22

beyond the cochlea, either along the auditory nerve, in areas of the brain that process speech, or in the central auditory system.