Brainscape's Knowledge GenomeTM

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


See full index

Year 2- CNS > Vestibular Function > Flashcards

Vestibular Function Flashcards

1
Q

What is the vestibular system about?

A

Balance and posture

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

Where is the vestibular system found?

A

Inner ear

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

What is the vestibular system made up of?

A

Fluid filled labyrinths which are embedded in the temporal bone

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

Which organ is the organ of hearing?

A

Cochlea

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

Which nerve sends sensory information from the ear to the brain?

A

Vestibular nerves, part of vestibulocochlear nerve (CN VIII)

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

What does the vestibular apparatus consist of?

A

3 semi-circular canals
Utricle
Saccule

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

What is the name given to the swelling at the base of the semi-circular canals?

A

Ampulla

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

What do the ampulla contain?

A

Sensory hair cells

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

What are the otolith organs?

A

Utricle and saccule

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

What does the utricle detect?

A

Back/front tilt of the head
Horizontal acceleration (as if you were in a car)

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

What does the saccule detect?

A

Vertical acceleration (as if you were in a lift).

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

What do the ampulla of the semi-circular canals detect?

A

Rotational acceleration (e.g. turning head quickly).

-?maybe remember this due to the fact they’re round and it’s rotational acceleration?

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

Where are the hair cells in the ampulla of the semi-circular canals embedded in?

A

Flexible gelatinous structure called the cupula

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

What does the cupula become distorted with?

A

Movement of endolymph within the canal

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

What happens when the cupula is distored?

A

Distorts the hair cells

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

What does distorting the hair cells of the cupula do?

A

Sets up an action potential in the vestibular nerve

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

How does the semi-circular canals detect rotational acceleration?

A

If rotating the skull to the left or right, the endolymph in semi-circular canals does not initially move as has a degree of inertia.
However, the ampulla moves instantly as is embedded in the skull.

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

Describe how dizziness occurs.

A

This might be a long one but it makes sense!!

If rotating at a constant velocity, the endolymph catches up and rotates at the same speed.
These can take several seconds but stops the shearing process, which drags the cupula through the endolymph.
However, when you stop spinning, the endolymph continues to move due to the momentum, creating a continuing sense of movement, causing dizziness.

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

Name the two types of cilia in hair cells.

A

Kinocilium
Stereocilia

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

Which is larger- kinocilium or stereocilia?

A

Kinocilium

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

What would happen if there was distortion of the cilia in the direction of the kinocilia?

A

Depolarisation would occur and would be increased firing of action potentials in the vestibular nerve

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

What would happen if there was distortion of the cilia in the direction away from the kinocilia?

A

Hyperpolarisation leading to decreased discharge on action potentials in the vestibular nerve

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

Which part of the brain controls balance?

A

Cerebellum

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

What is the name given to the sensory apparatus in the utricle and saccule?

A

Maculae

25
Q

Which plane of the utricle are the maculae orientated on?

A

Horizontal plane

(detect horizontal acceleration)

26
Q

Which plane of the saccule are the maculae orientated on?

A

Vertical plane
(detect vertical acceleration)

27
Q

The maculae, like the ampulla, have a set of cilia. What makes up this set of cilia?

A

One kinocilium and several stereocilia.

28
Q

What is embedded in the otolith membrane?

A

Calcium carbonate crystals

29
Q

What is the name given to the calcium carbonate crystals in the otolith membrane?

A

Otoliths

30
Q

A man tilts his head.
What detects this change?

A

Macula in the utricle
(horizontal plane).

31
Q

What happens to the otoliths when the head is moved?

A

Moves along with the otolith membrane

32
Q

A women goes into a lift. Which part of the vestibular system relays this information to the brain?

A

Vertical macula in saccule

33
Q

Kinesthesia?

A

Awareness of body position

34
Q

What does the tonic labyrinthine reflex do?

A

Keeps the axis of the head in a constant relationship with the rest of the body.

35
Q

What does the tonic labyrinthine reflex use information from?

A

Uses information from the maculae and neck proprioceptors.

36
Q

What does the dynamic righting reflex do?

A

Makes rapid postural adjustments that are made to stop you falling when you trip.

37
Q

In the vestibulo-cular reflexes, what is there strong association between?

A

Vestibular apparatus
Visual apparatus
Postural control

38
Q

What is meant by vestibular nystagmus?

A

Predictable eye movement in response to stimulation from the vestibular system.

39
Q

What happens in vestibule-ocular reflex?

A

Series of saccadic eye movements which rotate the eye against the direction of passive rotation of the head and body.

This means the original direction of gaze is persevered despite the head rotating.

Like you’re on a roundabout and you fix on a certain point until you can no longer see it.

40
Q

What is a nystagmus?

A

The rapid flick back movement of the eye

41
Q

If the rotation experienced is right, what direction will the nystagmus be?

A

Right

42
Q

You can use nystagmus to test vestibular function clinically. Name one the most common ways to test it.

A

Caloric stimulation

43
Q

Describe what happens in caloric stimulation.

A

-Outer ear is irrigated with a fluid warmer or colder than body temperature.
-This warms or cools the endolymph, causing it to behave in a different way.
-There will be a nystagmus.

44
Q

If during the caloric stimulation, you use fluid cooler than body temperature, what will the nystagmus be like?

A

Nystagmus away from the affected side

45
Q

If during the caloric stimulation, you use fluid warmer than body temperature, what will the nystagmus be like?

A

Nystagmus towards affected side

-> Remembers COWS
Cold=opposite
Warm=same

46
Q

Why is it important when getting ear wax irrigation that the fluid is at 37 degrees?

A

Prevents a nystagmus

47
Q

What can nystagmus cause for the patient?

A

Dizziness

48
Q

When may nystagmus take place?

A

Seen in patients with lesions in their CNS or PNS

49
Q

Kinetosis?

A

Motion sickness

50
Q

When is motion sickness most likely to occur?

A

When the visual and vestibular system inputs to the cerebellum are in conflict

51
Q

Why may someone get car sick?

A

Vestibular system is telling brain you are moving, visual system is telling brain you’re not

52
Q

Which symptoms are felt in motion sickness?

A

Nausea
Vomiting
Decreased BP
Dizziness
Sweating

53
Q

What is labyrinthitis?

A

Infection leading to interference with normal vestibular function.

54
Q

What symptoms are present in those with labyrinthitis?

A

All ANS symptoms present with motion sickness e.g. nausea, vomiting, decreased BP, dizziness
AND
Vertigo

55
Q

What is vertigo?

A

The perception of movement in the absence of movement

56
Q

What is Meniere’s disease?

A

A bit like labyrinthitis but no infection involved.
Associated with the overproduction of endolymph causing increase pressure.

57
Q

List some symptoms seen in those with Meniere’s disease.

A

Vertigo
Nausea
Nystagmus
Tinnitus

58
Q
A

Year 2- CNS (49 decks)

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