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Hugh's MD1 Neuro > Hearing > Flashcards

Flashcards in Hearing Deck (30)
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1
Q

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

A

Basilar on the bottom

Hair cells inbetween

Tentorial membrane on top

1
Q

Antibiotics and aspirin can effect hearing, how?

A

Damaging the outer hair cells

2
Q

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

A

Stereocilia

2
Q

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

A

They must move in the direction of the kinocilium

2
Q

What is the downstream effect of movement towards the kinocilium?

A

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

2
Q

What is special about the endolymph in the scala media?

A

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

2
Q

Which hemisphere is speech usually processed?

A

Left

3
Q

Where does integration of sound signalling from both ears occur?

A

In the brainstem - particularly the superior olivary complex

5
Q

Sclerosis of the ossicles causes what?

A

Profound effects on hearing

6
Q

Compare the roles of the outer and inner hair cells?

A

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

7
Q

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

A

Measuring the time for sound to arrive at each ear

7
Q

T/F Must hearing loss has a known cause?

A

False

9
Q

Why do you need impedance matching?

A

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

10
Q

How is the auditory cortex organised?

A

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

12
Q

The amplitude of sound determines its what?

A

Loudness

14
Q

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

A

Oval window

15
Q

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

A

Scala media

16
Q

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

A

The base (lateral end)

16
Q

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

A

Measuring the difference in intensity

17
Q

Which hemisphere is music usually processed?

A

Right

19
Q

What is the function of the outer hair cells?

A

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

20
Q

What are the membranes of the inner ear?

A

Basilar

Tentorial

21
Q

The wavelength of sound determines its what?

A

Pitch

22
Q

Which neurotransmitter do the hair cells release?

A

Glutamate

23
Q

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

A

Apex (medial end)

24
Q

What is the sequence of structures in the auditory pathway?

A

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

26
Q

How are the cilia structured?

A

Shortest to tallest - the tallest is the most important

28
Q

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

A

Aminoglycosides

29
Q

What are the important parts of the superior olivary complex?

A

Lateral and medial superior olives and the trapezoid body

30
Q

What is impedance matching?

A

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