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Hugh's MD1 Neuro > Hearing > Flashcards

Flashcards in Hearing Deck (30):
1

What is the order of positioning of the hair cells and two membranes

Basilar on the bottom

Hair cells inbetween

Tentorial membrane on top

1

Antibiotics and aspirin can effect hearing, how?

Damaging the outer hair cells

2

What is the name of the cilia on the hair cells?

Stereocilia

2

What must occur to the cilia for K channels to open?

They must move in the direction of the kinocilium

2

What is the downstream effect of movement towards the kinocilium?

K channels open > K influx > Depolarisation of the cell > Ca channels open > Neurotransmitter is released

2

What is special about the endolymph in the scala media?

It is high K - means there will be a K influx in response to channel opening

2

Which hemisphere is speech usually processed?

Left

3

Where does integration of sound signalling from both ears occur?

In the brainstem - particularly the superior olivary complex

5

Sclerosis of the ossicles causes what?

Profound effects on hearing

6

Compare the roles of the outer and inner hair cells?

Inner hair cells do must of the signal transduction for hearing while the outer ones amplify the movement of the membranes

7

How do you localise low frequency sounds in the horizontal plane?

Measuring the time for sound to arrive at each ear

7

T/F Must hearing loss has a known cause?

False

9

Why do you need impedance matching?

Because transferring sound from air to fluid is usually prevented by reflection

10

How is the auditory cortex organised?

Tonotopically - different areas are organised by the frequency they can process

12

The amplitude of sound determines its what?

Loudness

14

Through what do the ossicles transmit the vibrations from the tympani membrane to the inner ear?

Oval window

15

In which inner ear chamber does most of the important events occur?

Scala media

16

Which end of the basilar membrane deal with the high frequency sounds?

The base (lateral end)

16

How do you localise high frequency sounds on the horizontal plane?

Measuring the difference in intensity

17

Which hemisphere is music usually processed?

Right

19

What is the function of the outer hair cells?

Amplify the amount of vibration of the basilar membrane in response to efferent signal

20

What are the membranes of the inner ear?

Basilar

Tentorial

21

The wavelength of sound determines its what?

Pitch

22

Which neurotransmitter do the hair cells release?

Glutamate

23

Which end of the basilar membrane deals with low frequency sounds?

Apex (medial end)

24

What is the sequence of structures in the auditory pathway?

Hair cells > CNVIII > Cochlear Nucleus > Superior Olive > Lateral lemniscus > Inferior colliculus > Thalamus > Auditory cortex

26

How are the cilia structured?

Shortest to tallest - the tallest is the most important

28

Which type of antibiotic is particularly important in causing damage to outer hair cells?

Aminoglycosides

29

What are the important parts of the superior olivary complex?

Lateral and medial superior olives and the trapezoid body

30

What is impedance matching?

 Translating the info as sound waves in air to waves in fluid