Brainscape's Knowledge GenomeTM

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


See full index

Neuroscience > Auditory and Vestibular System > Flashcards

Auditory and Vestibular System Flashcards

1
Q

What two components make up the external ear?

A

Pinna and the external auditory meatus

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

What are the functions of the pinna?

A

collects sound waves, mobility enhances function

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

What is the function of the tympanic membrane?

A

separates external and middle ear

it is easily displaced by sound waves and takes sound waves and moves them to the middle ear

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

What structures make up the middle ear?

A

Ossicles which consist of three bones (malleus, incus, stapes)
Eustachian (auditory) tube

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

What is the function of the ossicles of the middle ear?

A

Concentrate sound waves striking the eardrum on smaller oval window
Provides a mechanical advantage in transmitting sound waves from air environment to fluid filled environment

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

What is the function of the eustachian (auditory) tube of the middle ear?

A

Equalize pressure across the ear drum
It is important for communication of the middle ear and oral cavity, we need to have this opening to depolarize pressure on both sides of the ear drum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The main structure of the inner ear is the…

A

cochlea

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

What are the three different chambers of the cochlea?

A

Scala vestibuli
Scala media
Scala tympani

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

List the structural components of the inner ear:

A 
Oval (cochlear) window
Round (vestibular) window
Scala media, tympani, and vestibuli
Reissner's (vestibular) membrane
Basilar membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The oval (cochlear) window opens into the…

A

scala vestibuli

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

The round (vestibular) window opens into the ….

A

Scala tympani

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

Scala media (cochlear duct) is between ….

A

Scala vestibuli and tympani

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

Reissner’s (vestibular) membrane separates….

A

scala vestibuli and media

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

Basilar membrane separates….

A

scala media and tympani

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

List the components of cochlea (inner ear structure) in top to bottom order:

A 
Scala vestibuli
Reisner's membrane
Scala media
Basilar membrane
Scala tympani
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When ear drum moves in, what are the movements of the oval window and round window?

A

Oval window moves in, round window moves out

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

Where is the organ of corti located?

A

on the basilar membrane of the Inner ear (cochlea)

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

What is the organ of corti and what is its main function?

A

It contains auditory hair cells that are sensory receptors that stimulate afferent fibers projecting into the CNS to CN CVIII. Its main function is sensory transduction that transduces mechanical inputs to chemical ones.

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

Afferent fibers stimulated by auditory hair cells are what kind of neurons and where are their cell bodies located?

A

Myelinated, bipolar cells; their cell bodies are located in spiral ganglion

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

What is the function of hair cells?

A

they are sensory receptors for hearing and vestibular function. They create a receptor potential based on the movement of their cilia and synapse with afferents and release neurotransmitters to stimulate afferents of CN VIII.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where are the distal ends of the cilia on auditory hair cells located?

A

They are embedded in an overlying membranous structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Membrane potential of hair cells is affected by what?

A

movement of cilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens when cilia of hair cells move towards the tallest cilia?

A

Depolarization of the hair cell membrane, which increases the release of neurotransmitter, causing increased firing of afferents to the CNS. (excitatory)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What happens when cilia of hair cells move away from the tallest cilia?

A

Hyperpolarization of the hair cell membrane, which decreases the release of neurotransmitter, causing decreased firing of afferents to the CNS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Do hair cells have action potentials?

A

No, they produce receptor potentials that will increase NT release which excites afferent fibers. It is the afferent fibers that have action potentials.

26
Q

What happens in the upward phase in regards to the inner ear?

A

Basilar membrane moves up, deflecting hair cells towards the longest cilia, depolarizing the membrane and releasing more excitatory NT.

27
Q

What happens in the downward phase in regards to the inner ear?

A

Basilar membrane moves down, moving cilia away from longest cilium, repolarizing the hair cell membrane, and decreasing release of excitatory NT

28
Q

What is the function of the inner ear?

A

eardrum moves in and out with sound waves. This causes oscillating fluid movements in scala vestibuli and tympani and the basilar membrane moves up and down. As a result, sterocilia are bent back and forth because their ends are embedded in the tectorial membrane. This causes ion channels to open and close, altering membrane potentials and causing receptor potentials to send information via neurotransmitters to CN VIII afferents.

29
Q

How is the basilar membrane and stereocilia tuned to frequencies?

A

The base of the basilar membrane (skinnier part) near the oval window is more sensitive to high frequencies. The apex of the basilar membrane (fatter part) at the end of the cochlea is more responsive to lower frequencies. This gives an animal the ability to detect changes in frequency of sound.

30
Q

How many synapses are there in the central auditory pathway for the afferents in CN VIII?

A

4

31
Q

Where is the first synapse of the central auditory pathway for CN VIII?

A

The first synapse is with dorsal and ventral cochlear nuclei and most axons cross trapezoid bodies, while some stay ipsiliateral. Axons ascend in the lateral lemniscus.

32
Q

Where is the second synapse of the central auditory pathway for CN VIII?

A

The second synapse is in the caudal colliculus and axons from here project in brachium of the caudal colliculus.

33
Q

Where is the third synapse of the central auditory pathway for CN VIII?

A

The third synapse is with the medial geniculate nucleus (thalamic relay). Axons from here project to cortex in internal capsule (on side of brain).

34
Q

Where is the fourth synapse of the central auditory pathway for CN VIII?

A

The fourth synapse is in the temporal cortex. This is the cortical area for hearing.

35
Q

List the 8 steps/locations in the central auditory pathway from where it starts to where it finishes.

A
  1. CN VIII afferents
  2. Synapse with Dorsal and ventral cochlear nuclei
  3. Cross trapezoid body
  4. Axons ascend in lateral lemniscus
  5. Second synapse in caudal colliculus
  6. Third synapse in medial geniculate
  7. Axons project to internal capsule
  8. Fourth synapse in auditory cortex.
36
Q

List the three structural components of the vestibular system.

A

Semicircular canals
Utricle and saccule
Vestibular afferents in CN VIII

37
Q

Two components of the semicircular canals are….

A

Crista, and cupula

38
Q

Crista of the semicricular canals is …

A

a sensory area in ampulla where hair cells are located

39
Q

Cupula of semicircular canals is a …

A

gelatinous structure where ends of hair cells are embedded

40
Q

What is the ampulla of the semicircular canal and what structures are located within it?

A

It is a widening of the loop where sensory (hair cells) are located. The crista and cupula are located in the ampulla.

41
Q

What is the name for the longest cilium?

A

Kinocilium

42
Q

What is the structure and function of the semicircular canals?

A

Canals are arranged in pairs in the same or parallel planes which allows for the bilateral representation of angular acceleration of any plan. These canals are therefore responsive to angular acceleration (turning movement).

43
Q

What happens in regards to the semicricular canals when the head turns?

A

Head turning bends sterocilia due to lag of endolymph movement. All hair cells in one canal on one side are depolarized or hyperpolarized by specific movmenet of head. Corresponding hair cells on opposite side show opposite changes.

44
Q

Semicircular canals project to _____ in the brain.

A

Vestibular nuclei

45
Q

What is the main function of semicircular canal input?

A

Coordination of head and eye movements.

46
Q

What is nystagmus and is it normal?

A

It is part of normal visual tracking. It is the slow movement of the eyes in opposite direction but at the same speed as the head turn. This is followed by fast movement in the same direction as turn. This movement is involuntary and mediated by semicircular canals.

47
Q

Is nystagmus involuntary or voluntary?

A

Involuntary

48
Q

What mediates nystagmus?

A

Semicircular canals

49
Q

Utricle and Saccule of vestibular system are also referred to as…

A

otolith organs

50
Q

Otolithic membrane contains…

A

CaCO3 crystals called otoliths

51
Q

Describe structure and function of the otolith organ.

A

The otoliths in the otolithic membrane cause otolithic membrane to have a higher specific gravity than water. The utricle and saccule are sensitive to the effects of gravity because of this and the lienar acceleration or tilt of head causes otolithic membrane to move and bend hairs.

52
Q

Utricle and saccule project to _____ in the brain.

A

Lateral vestibular nuclei

53
Q

What is the main function of otolith organ input?

A

Postural support, anti-gravity muscles

54
Q

True or false. Semicricular canals are responsive to gravity.

A

False, utricle and saccule are responsive to gravity

55
Q

What structure in the vestibular system plays a role in head turning?

A

Semicircular canals which coordinate head and eye movement

56
Q

What structure in the vestibular system plays a role in head tilt or linear acceleration of the head?

A

Otolith organs (utricle and saccule)

57
Q

Central vestibular pathways are _____ pathways.

A

Upper motor neuron pathways.

58
Q

Where do the rostral cerebellar nucleus and the medial cerebellar nucleus receive afferents from and where do they project?

A

They receive afferents from semicircular canals and send projection in medial longitudinal fasciculus that goes into cranial nuclei III, IV, and VI (nerves that effect extraoccular muscles) important for coordinating head and eye movement.

59
Q

Where does the medial vestibular nucleus recieve afferents from and where does it descend?

A

It recieves input from the semicircular canal and it descends only to the upper thoracic cord because its only interest is coordinating head and eye movement.

60
Q

From where does the lateral vestibular nucleus recieve afferents and what does it give rise to?

A

It recieves afferents from the utricle and saccule. It projects to the descending tract called the lateral vestibulospinal tract that helps resist effects of gravity to maintain upright posture.

61
Q

True or false. There is some input to medial geniculate nucleus and to several areas of the parietal and temporal cerebral cortex.

A

True

Neuroscience (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions