Vestibular Anatomy Flashcards Preview

Adult Neuro > Vestibular Anatomy > Flashcards

Flashcards in Vestibular Anatomy Deck (53)
Loading flashcards...
1

Signs and Symptoms of Vestibular Dysfunction

Dizziness
Blurry Vision
Nystagmus
Tinnitus
Vertigo
Hearing loss
Loss of balance & possible falls
Broad-based stance (to accommodate for imbalance)
Sweating, nausea, and vomiting (due to ANS involvement)

2

What are the two main reflexes of the vestibular system?

VOR: Vestibulo-ocular Reflex
VSR: Vestibulo-spinal Reflex

3

What are head movements detected by?

cupula

4

Vestibulo Ocular Reflex

Stabilizes eye in space
Necessary to see while head is in motion

5

Components of VOR:

angular and linear VOR

6

Vestibulo-Spinal Reflex

Stabilizes body
Helps maintain desired orientation to environment

7

Cervical Reflexes

cervicoocular reflex
cervicocollic reflex
cervicospinal reflex

8

Cervicoocular Reflex (COR)

Weak reflex
Does not play direct role in gaze stability
May help VOR to compensate
Proprioceptors and somatosensory receptors
-C1-C2 dorsal nerve roots

9

Cervicocollic Reflex (CCR)

Provides head stability
Contraction of stretched muscles to align head

10

Cervicospinal Reflex (CSR)

acts in conjuction with the VSR
-provides postural stability through limb activation

11

Three axes of rotation:

roll
pitch
yaw

12

Three axes of translation

AP
lateral
vertical

13

Pitch:

up and down

14

Yaw

head movement side to side in horizontal plane (shaking head no)

15

Roll

lateral side bending

16

What do semicircular canals detect?

angular rate

17

What do otoliths (saccule and utricle) detect?

linear acceleration

18

Functions of peripheral vestibular system:

Stabilization of visual images on the fovea of the retina during head movement to allow clear vision
Maintain postural stability especially during movement of the head
Provide information used for spatial orientation

19

Peripheral vestibular components:

Semicircular canals (SCC)
Utricle
Saccule
CN VIII: Vestibulocochlear nerve

20

Orientation of semicircular canals:

Anterior/superior
Lateral/horizontal
Posterior/inferior

21

What are the components of the labyrinth?

bony
membranous

22

Bony labyrinth:

3 semicircular canals
cochlea
vesitbule

23

What is the bony labyrinth filled with?

perilymphatic fluid (similar to cerebral spinal fluid)

24

What is the membranous labyrinth?

suspended within the bony section and contains membranous portions of the canals and utricle and saccule

25

What is the membranous labyrinth filled with?

endolymphatic fluid (similar to intracellular fluid)

26

Ampulla:

contain the cupula (hair cells) which convert displacement into neuro firing thru bending of hair cells

27

What does ampulla detect?

linear/angular motion

28

Otolith Organ

(Utricle and Saccule): contain calcium carbonate crystals called otoconia

29

What does otolith organ detect?

gravity and acceleration

30

Sensory organ of angular VOR:

Semi-Circular Canals:
Horizontal
Anterior
Posterior