Brainscape's Knowledge GenomeTM

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


See full index

NMR II > Vestibular > Flashcards

Vestibular Flashcards

1
Q

What is the main purpose of the vestibular system?

A

Equilibrium

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

Where is the perilymph in the labyrinth? Where is the endolymph?

A

Perilymph lies between the bony and membranous labyrinth. Endolymph fills the membranous labyrinth.

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

Endolymph has a higher concentration of what ion?

A

Potassium

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

Describe the blood flow of the vestibular system.

A

Off of the basilar artery, we will AICA. AICA then bifurcates into the labyrinthine artery and the common cochlear artery.

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

What component of the vestibular system detects linear acceleration?

A

Vestibule (utricle and saccule)

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

What component of the vestibular system detects angular acceleration?

A

Semicircular canals

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

In the vestibular system, we have hair cells. Identify the specific types, and how they send action potentials.

A

The vestibular system has one kinocilium and many stereocilia. To cause an action potential, the stereocilia will “knock over” the kinocilia, leading to depolarization. If the kinocilia knock the stereocilia over, we will get hyperpolarization and no action potential.

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

Does the utricle or saccule detect horizontal motion? Which one does vertical?

A

The utricle does horizontal motion, while the saccule does vertical motion.

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

The utricle and saccule each contain a ________.

A

Macula

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

What are maculae?

A

Both the utricle and saccule have a gelatinous mass, the macula, and cilia from a sheet of hair cells are embedded within.

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

Maculae are oriented how in the utricle? Saccule?

A

It is oriented horizontally in the utricle and vertically in the saccule.

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

Maculae have crystals embedded in them called ________.

A

Otoconia.

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

The ampulla is located in which part of the vestibular system?

A

Semicircular canals

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

The ampulla houses what, and what is its function?

A

Crista; it is an elevated ridge of tissue that contains the hair cells.

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

What is the cupula?

A

Gelatinous mass in which stereocilia are embedded; is connected to the roof of the ampulla.

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

True or False: In the cupula, the kinocilia and stereocilia are only oriented one way.

A

True

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

If you turn your head to the left, which semicircular canal are you exciting? Which are your inhibiting?

A

Excite the left and inhibit the right horizontal semicircular canal because the stereocilia will knock the kinocilia over on the left side.

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

If there is disagreement occurring between the push-pull mechanism, what will happen?

A

Vertigo and nausea

19
Q

Peripheral vs the central process of the Scarpa’s ganglion.

A

Peripheral process innervates hair cells. Central process forms CN 8.

20
Q

Route of CN 8.

A

Travels through the internal acoustic canal and enters the brainstem and terminates in 4 main vestibular nuclei. Some afferent fibers terminate directly on the cerebellum on the Flocculonodular lobe.

21
Q

Flocculonodular lobe gives us immediate information about what?

A

Where our head is in space.

22
Q

The lateral vestibular tract terminates where?

A

In the spinal cord.

23
Q

Importance of our lateral vestibular nucleus and tract.

A

Provides an important route for cerebellar regulation of muscle tone, specifically extension tone. If we have a cerebellar lesion, it usually results in low tone.

24
Q

What is the relationship between the vestibular tract and reticular formation?

A

There are connections between the vestibular nuclei complex and the adjacent reticular formation. So, this is why a patient will feel nauseous, sweaty, and have increased HR because this is what our reticular formation is involved in.

25
Q

Vestibulospinal reflex

A

Lateral vestibulospinal tract; maintains posture by exciting extensor tone.

26
Q

Vestibulocollic Reflex

A

Medial vestibulospinal tract; reflexive neck control (head righting reaction).

27
Q

VOR

A

Stabilizes visual image during head movement. Causes eye to move simultaneously in opposite direction and in equal magnitude of our head.

28
Q

If you activate your left vestibular nerve, your head is turning left or right?

A

Left

29
Q

Does the abducens nerve control the ipsilateral or contralateral lateral rectus? Medial rectus?

A

The Abducens nerve controls the ipsilateral lateral rectus and contralateral medial rectus through the ipsilateral oculomotor nerve on the side of the muscle.

30
Q

How are the abducens nerve and oculomotor nerve connected?

A

Through the MLF.

31
Q

What is nystagmus?

A

Disorder of ocular motor instability resulting in spontaneous, involuntary, rhythmic oscillations of the eyes.

32
Q

Nystagmus is named for its ___________ phase.

A

Fast phase, beating towards the more neuronal side.

33
Q

If nystagmus is purely upbeat or downbeat, are we thinking peripheral or central?

A

Central

34
Q

Spontaneous nystagmus refers to the absence of _____ or _______ stimulation.

A

Visual or vestibular

35
Q

Gaze-evoked nystagmus

A

Eyes cannot be maintained at an eccentric orbital position and are pulled back toward the primary position by elastic forces of the orbit.

36
Q

If peripheral, will gaze-evoked nystagmus stay in the same direction or change? Central?

A

If peripheral, it should not change direction; if central, it will change direction.

37
Q

Name characteristics of peripheral vestibular deficits.

A

Severe vertigo
Days to weeks duration
Hearing loss, tinnitus associated
Nystagmus: usually mixed, unidirectional, follows Alexander’s Law, dampened with visual fixation.

38
Q

Name characteristics of central vestibular deficits.

A

None or mild vertigo
Often chronic
Nystagmus: may be purely vertical or torsional. visual fixation usually has no effect

39
Q

What are the unilateral hypofunctioning conditions in the PNS?

A

Vestibular neuritis/labryinthitis
Meniere’s Disease
Perilymphatic fistula
Acoustic neuroma
Vestibular paroxysmia

40
Q

What are CNS conditions that contribute to dizziness?

A

Migraine
Mal de Debarquement Syndrome
VBI or BS stroke
Cervicogenic

41
Q

Vestibular neuritis is caused by what?

A

Infection resulting in swelling and hypofunctioning of the vestibular nerve.

42
Q

Labyrinthitis is caused by what?

A

Inflammation of the entire CN 8; results in hearing loss.

43
Q

In vestibular neuritis, if you lose the left of your nerve, your brain will think you are spinning to the right or left?

A

Right

NMR II (1 decks)

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