Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BRS2 Neurology > Auditory System > Flashcards

Auditory System Flashcards

1
Q

List the 3 sections the ear is divided into.

A

Outer, middle and inner ear

Each part has a specific function during the hearing process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the ear embedded?

A

The organ is embedded in the petrous portion of the temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the hardest bone in the body?

A

Petrous portion of the temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 2 outer ear structures?

A

Pina and external auditory meatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List the outer ear functions.

A

To capture sound and to focus it to the tympanic membrane.
To amplify some frequencies by resonance in the canal.
To protect the ear from external threats (cilia prevents external elements from entering in from the air), the wax provides a mechanical function by covering the inner ear and provides an unfavourable pH to pathogens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the main function of the middle ear?

A

Amplification by:

  • Focusing vibrations from large surface area (tympanic membrane) to small surface area (oval window). The change in surface area means the pressure is increased.
  • Using leverage from the incus-stapes joint to increase the force on the oval window.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What 3 structures articulate with each other to facilitate the transmission of sound into the inner ear?

A

Malleus, incus and stapes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the hearing part of the inner ear?

A

Cochlea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the relationship between surface area and pressure.

A

Inversely proportional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the function of the inner ear?

A

To transduce vibration into nervous impulses. While doing so, it also produces a frequency (or pitch) and intensity (or loudness) analysis of the sound.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The cochlea contains 3 compartments. Name them.

A

Scala vestibuli
Scala media
Scala tympani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What 2 compartments of the cochlea are bone structures containing perilymph (high in sodium)?

A

Scala vestibuli and scala tympani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the Scala media?

A

Membranous structure containing potassium-rich endolymph. The hearing organ, the Organ of Corti resides within the scala media of the cochlea.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Is the perilymph high in sodium or potassium?

A

Perilymph HIGH IN SODIUM whereas endolymph is high in potassium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where is the hearing organ or Organ of Corti located?

A

Scala media of cochlea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the name of the structure that the organ of Corti lies in?

A

Basil membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe how the basilar membrane is arranged.

A

Arranged tonotopically using the same principle as a xylophone whereby frequency-sensitive cells are arranged from high to low frequency from base to apex respectively.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Explain the arrangement of hair cells in the Organ of Corti.

A

Contains inner and outer hair cells. Inner hair cells are arranged in single columns whereas outer hair cells are arranged in columns of three.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where is the tectorial membrane located relative to the hair cells and what is its purpose?

A

The tectorial membrane is located above the hair cells and will allow the hair deflection, which in turn will depolarise the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are OHC and IHC in contact with the tectorial membrane?

A

No, only OHC hair are in constant contact with the tectorial membrane and these assist the contact with the IHC.

21
Q

What is the function of IHC in the Organ of Corti?

A

IHC carry 95% of the afferent information of the auditory nerve. Their function is the transduction of the sound into nerve impulses.

22
Q

What is the function of OHC in the Organ of Corti?

A

Carry 95% of efferents of the auditory nerve. Their function is modulation of the sensitivity of the response.

23
Q

Explain the process of transduction.

A

Deflection of the stereocilia towards the longest cilium will open K+ channels within the inner hair cell, as the tectorial membrane is brought into contact. Ionic interchange of potassium within the endolymph and inner hair cell leads to cell depolarisation. Depolarisation induces the opening of VGCCs which release excitatory NTs (Glutamate) onto the afferent nerve.

24
Q

What is the relationship between amplitude of sound and deflection of sterocilia causing K+ channel opening?

A

Higher amplitudes of sound will cause greater deflection of stereocilia and K+ channel opening.

25
Q

What are the hair of the hair cells called?

A

Stereocilia

26
Q

In transduction what will open K+ channels and what will close K+ channels?

A

Depolarisation - opens K+ channels

Hyper-polarisation - closes K+ channels

27
Q

Explain the auditory pathways in the human body.

A

Spiral ganglions from each cochlea project via the auditory vestibular nerve (VIII) to the ipsilateral cochlear nuclei (monoaural neurons).
Auditory information crosses the superior olive level, beyond this point all connections are bilateral. Ultimately information is relayed to the auditory cortices located within the temporal lobe.

28
Q

Use one word to describe how hearing is organised.

A

Tonotopically

29
Q

Define frequency

A

Frequency/pitch (Hz) - Cycles per second, perceived tone

30
Q

Define amplitude.

A

Amplitude/loudness (dB) - Sound pressure, subjective attribute correlated with physical strength.

31
Q

Define the human range of hearing for both frequency and amplitude.

A

Frequency: 20-20,000 Hz
Loudness: 0dB-120dB sound pressure level (SPL)

32
Q

What type of scale is the decibel scale?

A

Logarithmic scale

33
Q

Why is the decibel scale useful?

A

Because the range of sensitivity is very large. This allows us to compress the scale on a graph, and reflect the fact that many physiological processes are non-linear (i.e. they can respond to both very low and very high values).

33
Q

Why is the decibel scale useful?

A

Because the range of sensitivity is very large. This allows us to compress the scale on a graph, and reflect the fact that many physiological processes are non-linear (i.e. they can respond to both very low and very high values).

34
Q

Does hearing acuity decrease with age?

A

Yes, particularly with higher frequencies. Medium and low frequencies could be affected with the progression of a hearing loss.

35
Q

What are the aims of the hearing assessment?

A

To answer these questions:
Is there a hearing loss? If yes:
- Of what degree?
- Of what type?

36
Q

List the procedures involved in a hearing assessment.

A 
Tunning fork
Audiometry
Central processing assessment
Tympanometry
Otoacustic Emission
Electrocochleography
37
Q

What is the use of a tuning fork in the hearing assessment?

A

Used to establish the probable presence or absence of a hearing loss with a significant conductive component. They are used to provide early and general information, when audiometry is not available or possible.

38
Q

What is Pure Tone Audiometry?

A

Science of measuring hearing acuity for variations in sound intensity and frequency. An audiometer is the device used to produce sound of varying intensity and frequency.

39
Q

Describe how you would complete the Weber test.

A

Place tuning fork against knee or elbow and then place the base of the form in the midline on the patient’s forehead. Ask the patient whether the sound is louder in any particular ear.
Unilateral conductive hearing loss - sound will be heard louder in the deaf ear.
Unilateral sensorineural hearing loss - sound will be heard louder in the normal ear.

40
Q

Describe how you would complete the Rinne test.

A

Compares air conduction with bone conduction.
Place base of vibrating tuning fork against the patient’s mastoid process (Allow for 2-3 seconds to appreciate intensity of sound). Lift the fork off the mastoid process and place the vibrating tips about 1cm from their external auditory meatus.

41
Q

Explain what an audiogram is.

A

The audiogram is where the hearing thresholds are plotted to define if there is a hearing loss or not. A normal hearing threshold is located between 0-20dB.

42
Q

What is the Central Processing Assessment?

A

Assessment of hearing abilities other than detection. This involves sound localisation, filtered speech and speech in nose. Focused on assessing sound discrimination and comprehension.

43
Q

What is the Tympanometry examination used to test?

A

Condition of the middle ear and mobility of the ear drum (tympanic membrane) and the ossicles by generating variations of air pressure in the ear canal.

44
Q

List the most common results of tympanometry.

A

A - Normal
C - Negative middle ear pressure
B - Middle ear effusion, perforation of tympanic membrane, Eustacian (pharyngotympanic) tube dysfunction, occluded ear canal.

45
Q

What is compliance of the the middle ear?

A

How effectively sound is transmitted into the middle ear.

46
Q

The normal cochlea produces low intensity sounds called what?

A

Otoacoustic Emissions (OAEs)

47
Q

What are OAEs produced specifically by?

A

Outer hair cells as they expand and contract.

48
Q

What test is often part of the newborn hearing screening and hearing loss monitoring?

A

Otoacoustic Emissions (OAEs)

BRS2 Neurology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions