Audio 1

Question 1

The auditory system is designed to transform acoustic information into _______ and ultimately to ______

Answer 1

mechanical activity

electrochemical signals

Question 2

The outer ear is made up

Answer 2

the pinna and external auditory meatus

Question 3

The middle ear begins with the _______, and includes the ossicular chain (with all the associated muscles, ligaments, and tendons), and the Eustacian tube.

Answer 3

tympanic membrane

Question 4

Sound is

Answer 4

long waves passing through medium

Question 5

We get areas of rarefaction and compression over and over which translates into

Answer 5

pitch and frequency

Question 6

The inner ear begins at the _______, and includes the :

Answer 6

oval window

cochlea and vestibular structures.

Question 7

The pinna and ear canal provide a boost in

Answer 7

high frequency sound intensity~ External ear acoustic gain

Question 8

middle ear is a ______, and consists of the ossicular chain that extends from the

Answer 8

mechanical system
tympanic membrane (ear drum) to the oval window of the inner ear.

Question 9

transmits sound pressure waves from air to fluid

Answer 9

middle ear mechanics

Question 10

Three ways of middle ear impedence matching

Answer 10

area ratio
lever action
bucking of TM

Question 11

Total gain of middle ear

Answer 11

31 dB, enough to overcome impedence mismatch

Question 12

Area ratio principle:

Answer 12

go from Tympanic membrane with large area, same force, low pressure–>
smaller area, same force, HIGH pressure
Gives us 23 dB gain

Question 13

Lever Action principle:

Answer 13

Length of malleus is longer then process of incus:
More distance, less force–> less distance, more force
~2dB gain

Question 14

Ossicular chain: the length of the _____ is longer then the process of the _____

Answer 14

malleus

incus

Question 15

Buckling of TM

Answer 15

The TM buckles when vibration occurs and applies almost twice the force to malleus
~6 dB

Question 16

The inner ear is contained in the _______, and is encased in a bony structure called the osseous or bony labyrinth.

Answer 16

petrous apex of the temporal bone

Question 17

The labyrinth consists of three continuous sections:

Answer 17

the vestibule, the cochlea, and the semicircular canals.

Question 18

The initial point of communication between the middle and inner ears occurs at

Answer 18

the oval window of the vestibule where the stapes footplate abuts the oval window membrane

Question 19

The core of the cochlea is the _______which is highly porous bone that allows passage of auditory nerve fibers as they travel from the internal auditory meatus to the hair cell synapse.

Answer 19

modiolus,

Question 20

Extending from the modiolus into the osseous labyrinthine space is a bony shelf, or the

Answer 20

osseous spiral lamina

Question 21

Spiral lamina provides partial division of the
cochlea, the upper:
the lower:

Answer 21

scala vestibuli

scala tympani

Question 22

the scala vestibuli and scala tympani communicate at

Answer 22

helicotrema

Question 23

spiral lamina is also the point of attachment for the basilar membrane, which is the lower border of the membranous labyrinth encasing the

Answer 23

scala media.

Question 24

scala media bordered superiorly by _______ and inferiorly by the ________

Answer 24

Reissner’s membrane

basilar membrane

Question 25

the organ of Corti located in

Answer 25

membranous labyrinth

Question 26

stria vascularis in the membranous labyrinth is in charge of

Answer 26

metabolic environment of the scala media

–blood supply and ionic conc = cochlear battery (scala media very metabolically active)

Question 27

The organ of Corti runs longitudinally along the length of the ______ and consists of many types of epithelial cells and structures.

Answer 27

basilar membrane

Question 28

One row of _____and three rows of ______ are present, and the cell bodies are surrounded by supporting cells.

Answer 28

inner hair cells

outer hair cells

Question 29

Perilymph is found in
with High
and Low

Answer 29

scala vestibuli
high Na
low K

Question 30

endolymph is found in
with high
and low

Answer 30

scala media
K
Na

Question 31

Hair cells are contacted by the dendrites of ______ whose cell bodies are in the spiral ganglion.

Answer 31

afferent bipolar neurons

Question 32

The basilar membrane is like a

Answer 32

traveling wave

Question 33

high frequency/pitch will get off at

Answer 33

the base or right away on basilar membrane

Question 34

low pitch/frequency will get off basilar membrane at

Answer 34

apex or later

Question 35

90-95% bipolar neurons contact ________ 5-10% contact _______.

Answer 35

inner hair cells;

outer hair cells

Question 36

Many afferent fibers synapse on the same_____ , while single afferent fibers branch to synapse with _______.

Answer 36

inner hair cell

several outer hair cells

Question 37

Efferent fibers have cell bodies in the _______ of the brainstem and synapse directly on outer hair cells and on the afferent fibers of inner hair cells.

Answer 37

superior olivary complex

Question 38

concept that dif frequencies will displace basilar membrane at dif points

Answer 38

tonotopic organization

Question 39

Inner and outer hair cells function as receptor cells that transduce mechanical movement into an

Answer 39

electrochemical signal to stimulate the auditory nerve.

Question 40

passive transducers of auditory system

Answer 40

inner hair cells

Question 41

Outer hair cells have microfilaments and microtubules along the length of the cell that give rise to ______

Answer 41

motile activity.

Question 42

The motile properties of microfilaments on outer hair cells result in

Answer 42

increased basilar membrane motion and are responsible for the cochlear amplifier.

Question 43

Rooted in the cuticular plate of each hair cell and projecting through the reticular lamina are bundles of actin filaments called ______, stiff hair-like structures that deflect with mechanical disturbances.

Answer 43

stereocilia

Question 44

stiff hair-like structures that deflect with mechanical disturbances.

Answer 44

stereocilia

Question 45

Stereocilia are connected to each other by filamentous ___________. These ensure that the connected stereocilia move as a unit when the longer stereocilia are deflected

Answer 45

cross-links and tip-links

Question 46

Movement of the endolymph produces deflection of the :

Answer 46

sterocilia

Question 47

Deflection of the stereocilia (in one direction) opens

Answer 47

ion channels of sterocilia– Positive ions flow inward, through open channels, depolarizing the hair cell

Question 48

Once sterolia open up…positive ions flow in and

Answer 48

depolarize the hair cell causing NT release–> stim auditory nerve fibers

Question 49

Endolymph in scala media is high in

Answer 49

K+~ 80mV

Question 50

Inner hair cells have charge of

Answer 50

-45 mV bc the reticular lamina keeps them seperate

Question 51

Perilymph in scala tympani has charge of

Answer 51

0 mV with low K+mV

Question 52

Positive ions (K+) from endolymph flow in and \_\_\_\_\_\_
when tiplinks open

Answer 52

depolarize hair cells

Question 53

We get depolarization during the _____

and hyperpolarization during the ______

Answer 53

upward phase

downward phase

Question 54

Obstruction or anomoly at middle ear or external ear, something is blocking sound coming in d/t

Answer 54

Conductive hearing loss

Question 55

Sensorineural hearing loss tends to be

Answer 55

permanent

Question 56

Dysfunction of the cochlea and/or auditory nerve.

Answer 56

Sensorineural hearing loss:

Question 57

Hearing is tested by measuring detection thresholds to stimuli. The detection thresholds are plotted on an

Answer 57

audiogram