Vestibular System Flashcards
(84 cards)
1
Q
Is the vestibular system the auditory or non auditory portion of the inner ear
A
Non auditory
2
Q
True or False:
The vestibular system is the oldest sensory system in humans
A
True
3
Q
What does the vestibular system do
A
Responds to movement of the head relative to space and gravity
4
Q
How does the vestibular system responds to movements of the head relative to space and gravity
A
Using inertial sensing receptors that sense movement in each of the six degrees of freedom
5
Q
What are the 2 categories of degrees of freedom
A
- 3 Translational
2. 3 Rotational
6
Q
What are the 3 purposes that the vestibular apparatus serves in humans
A
- Plays the dominant role in the subjective sensation of motion and spatial orientation of the head
- Adjusts muscular activity and body position to maintain posture
- Stabilizes in space the fixation point of the eyes when the head moves
7
Q
True or False:
There is no primary cortex for vestibular info so there is multiple places that info goes
A
True
8
Q
What are the 2 basic questions about human perception that the vestibular apparatus answers
A
- Where am I going
2. Which way is up
9
Q
What is the where I am going equal to
A
Head linear acceleration
10
Q
What type of motion tells you where you are going
A
Translational motion including gravity
11
Q
What determines the where I am going question
A
Otoliths
12
Q
Where are the otoliths housed (2)
A
Saccule and utricle
13
Q
What is the saccule important for
A
Up and down
14
Q
Which way is the saccule oriented
A
Vertical
15
Q
Which way are the saccule hairs oriented
A
Horizontal
16
Q
What is the utricle important for
A
Side to side motion
17
Q
Which way is the utricle oriented
A
Horizontal
18
Q
Which way are the utricle hairs oriented
A
Vertical
19
Q
What is the which way is up equal to
A
Head angular acceleration
20
Q
What type of motion tells you which way is up
A
Rotational motion
21
Q
What determines the which way is up question
A
Semicircular canals
22
Q
True or False:
Part of the vestibular pathways is directly to the eye muscles
A
True
23
Q
What does the peripheral sensory apparatus do (2)
A
- Detects and relays info about head angular and linear velocity to central processing system
- Orients the head with respect to gravity
24
Q
What does the central processing system of the vestibular apparatus do
A
Processes information in conjunction with other sensory inputs for position and movement of head in space
25
What does the motor output system do
Generates compensatory eye movements and compensatory body movements during head and postural adjustments
26
True or False:
| The vestibular system only provides sensory info about the head
True
27
What distributes this signal to head movement and postural systems for head and limb stabilization
The central vestibular system
28
What 2 systems work together with the eye muscles to form a control system that enables us to maintain an erect posture
1. Vestibular system
| 2. Postural systems
29
What does the vestibule contain
Saccule and utricle
30
What type of motion do the semicircular canals do
Rotational
31
What type of motion does the vestibule do
Translational
32
True or False:
| The vestibular system is a chamber in a chamber
True
33
What fluid is shared by the vestibular and cochlear system
The perilymph
34
What do the auditory and vestibular systems have in common (3)
1. Common fluid system
2. Hair cell motion detectors
3. Innervation
35
What is an issue with having a common fluid system
If there is something wrong with the fluid system both hearing and balance will be affected
36
What frequency is detected for hearing
High frequency
37
What frequency is detected for balance
Low frequency
38
True or False:
| A tumor that compresses CN VIII after the branches join can affect both hearing and equilibrium
True
39
What are receptors in the ampullae are called
Cristae
40
What are the cristae responsible for
Allowing a person to receive changes in angular acceleration
41
Receptors in the otolith system are called
Maculae
42
What are the maculae responsible for
Allowing a person to receive changes in linear acceleration in the horizontal and vertical directins
43
What is located in the ampullae
Capula
44
What is the function of the capula
Stimulate the hair cells when the endolymph displaces the capula
45
What are the otoliths composed of
Calcium carbonate
46
What are the short hair cells
Stereocilia
47
What are the long hair cells
Kinocilia
48
What are the motion detecting receptors in the vestibular system
Hair cells
49
Which direction do the hair cells have to bend to cause an excitatory signal (depolarization)
From short to long hair cells
50
Which direction do the hair cells have to bend to cause an inhibitory signal (hyperpolarization)
From long to short
51
What are the 2 divisions of the vestibular portion of CN VIII
1. Superior division
| 2. Inferior division
52
What is included in the superior division of the vestibular portion of the CN VIII (3)
1. Utricle
2. Anterior part of saccule
3. Horizontal and anterior canals
53
What is included in the inferior division of the vestibular portion of the CN VIII (2)
1. Posterior part of saccule
| 2. Posterior canal
54
Where do the superior and inferior divisions go
The superior division goes to the superior ganglion
| The inferior division goes to the inferior ganglion
55
Where does the information from the vestibular portion of CN VIII travel (2)
1. Vestibular nuclei
| 2. Cerebellum
56
Where do the vestibular nuclei project (5)
1. Spinal cord
2. Oculomotor nuclei
3. Reticular formation
4. Cerebellum
5. Thalamus (conscious aspect)
57
Where are the primary sensory neurons located for the vestibular pathways
Vestibular gnaglia
58
Where do primary axons terminate for the vestibular pathways (2)
1. Vestibular nuclei
| 2. Cerebellum
59
How many descending tracts do the vestibular nuclei give rise to
2
60
What are 2 descending tracts of the vestibular nuclei
1. Medial vestibulospinal tract (neck)
| 2. Lateral vestibulospinal tract (LE)
61
What do the ascending axons from the vestibular nuclei form
Medial longitundinal fasciculus (MLF)
62
Where do axons of the medial longitudinal fasciculus terminate (3)
Cranial nerve nuclei III, IV, VI
63
True or False:
| The vestibular system provides rapid sensory indication of the rotation or linear movement of the head
True
64
True or False:
The vestibular apparatus sends signals to the vestibular nuclei in the dorsal surface of the medulla via the vestibulocochlear nerve
True
65
What are the 4 vestibular nuclei that receive distinct but overlapping information
1. Superior
2. Medial
3. Lateral
4. Inferiror
66
Where does the medial vestibulospinal tract originate in general
Medial vestibular nucleus
67
Where does the medial vestibulospinal tract descend
Ipsilateral and bilaterally to cervical levels of the cord
68
Where does the lateral vestibulopinal tract originate in general
The lateral, inferior, and superior vestibular nuclei
69
True or False:
| The lateral vestibular nuclei receive input from the vestibulocerebellum
True
70
Where does the lateral vestibulospinal tract descend
Ipsilateral to all levels of the cord
71
True or False:
| Both the medial and lateral vestibulospinal tracts innervate proximal muscles
True
72
True or False:
| The medial vestibulospinal tract receives predominantly a semicircular canal signal
True
73
What does the medial vestibulospinal tract do
Keeps the head still in space
74
True or False: The lateral vestibulospinal tract receives predominantly an otolith signal
True
75
What does the lateral vestibulospinal tract do
Allows the legs to adjust for head movements
76
How does the lateral vestibulospinal tract allow the legs to adjust for head movements
By providing excitatory tone to extensor muscles
77
What happens when there is loss of inhibition from the cerebral cortex and cerebellum on the lateral vestibulospinal tract
Decerebrate rigidity
78
True or False:
| Some vestibular nucleus neurons send projections to the cerebellum via the inferior cerebellar peduncle
True
79
Where do most of the afferents that go to the cerebellum innervate
The flocculonodular node
80
True or False:
| Many interconnections are found between the vestibular nuclei and the cerebellum which coordinate postural adjustments
True
81
Where do vestibular nucleus neurons send projections for vestibulo-autonomic control (3)
1. Reticular formation
2. Dorsal pontine nuclei
3. Nucleus of the solitary tract
82
What do the vestibulo-autonomic connections regulate (3)
1. Breathing
2. Circulation
3. Induction of motion sickness and emesis
83
How do the vestibulo-autonomic connections regulate circulation
Through compensatory vestibular autonomic responses that stabilize respiration and blood pressure during body motion and changes relative to gravity
84
What are the vestibular sign and symptoms (7)
1. Dizziness
2. Vertigo/spinning
3. Imbalance/gait deficits/falls
4. Visual blurring (oscillopsia) or impaired vision
5. Hearing loss and/or tinnitus
6. Lightheadedness
7. Feelings of disorientation, rocking, swaying, floating, disconnected
