Vestibular system 10/28/16

Question 1

What are the three systems that help keep a person upright?

Answer 1

• Cerebellum
• Vision
• Vestibular system

Question 2

What are the first responses (involuntary/reflex) when a person trips?

Answer 2

• Arms go out
• Head goes back
• Back arches

Question 3

What are the three major divisions of the vestibular system?

Answer 3

• Peripheral apparatus
• Central vestibular nucleus
• Sensory Interactions

Question 4

What innervates the vestibular apparatus?

Answer 4

-Scarpa Ganglion

Question 5

How many canals do you find on the vestibular apparatus?

Answer 5

Three

Question 6

What are the names of the three canals in the vestibular system?

Answer 6

• Anterior (superior)
• Horizontal
• Posterior

Question 7

What two features help with gravity detection in the vestibular system?

Answer 7

• Utricle

- Saccule

Question 8

Under normal motion what way is our head tilted?

Answer 8

30 degrees down

Question 9

What fluid goes into the peripheral apparatus from the CSF and how?

Answer 9

-Perilymph through the perilymphatic duct

Question 10

What ion is endolymph high in?

Answer 10

K+

Question 11

What ion is perilymph high in?

Answer 11

Na+

Question 12

Why is Na+ and K+ important in the peripheral apparatus?

Answer 12

To create gradients

Question 13

What creates the sensation in the peripheral apparatus?

Answer 13

Sensory Epithelial cells

Question 14

What do the semicircular canals sense?

Answer 14

-Angular motion

Question 15

What happens if the hair cells (epithelial sensory cells) pull?

Answer 15

K+ channels are opened

Question 16

What fluid hits the cupula to push/pull the hair cells?

Answer 16

-Endolymph

Question 17

What is the cupula?

Answer 17

-Gelatin filled bag around the hair cells

Question 18

What is linear acceleration?

Answer 18

Up and Down (gravity)

Question 19

What senses linear acceleration?

Answer 19

• Utricle

- Saccule

Question 20

What is the otolith membrane?

Answer 20

Structure that surround the hair cells involved with linear acceleration

Question 21

What is found on top of the otolith membrane that helps overcome inertia?

Answer 21

-Otoconia (bags of calcium)

Question 22

What does the signaling from the peripheral apparatus?

Answer 22

-Hair cells

Question 23

What is multimodal convergence?

Answer 23

Immediate integration with other sensory inputs

vestibule with the eye and brain etc..

Question 24

Where do you find the vestibular nucleus?

Answer 24

Pons and Medulla

Question 25

What are the four major subdivisions of the vestibular nucleus?

Answer 25

- Superior vestibular - Lateral vestibular - Medial vestibular - Inferior vestibular

Question 26

What type of motion do the horizontal and superior canal measure?

Answer 26

-Rotational

Question 27

Which canal places your eyes while moving?

Answer 27

-Horizontal canal

Question 28

What tracts do the superior vestibular nucleus run upward on?

Answer 28

-Medial longitudinal fasciulus (MLF)

Question 29

What does the vestibulo-cerebellar network provide coordination of?

Answer 29

- Posture - Balance - Eye Movements

Question 30

If you get drunk what part of the peripheral apparatus is offline?

Answer 30

-The semicircular canals

Question 31

What part of the peripheral apparatus interacts with the cerebellum?

Answer 31

-Semicircular canals

Question 32

What network coordinates your eyes and rotational movement?

Answer 32

-Vestibulo-ocular network

Question 33

Where is the control of the vestibulo-ocular network controlled?

Answer 33

-Pons

Question 34

What two muscles are involved in the vestibulo ocular network?

Answer 34

- Lateral rectus | - Medial rectus

Question 35

If you turn your head left quickly what direction does your eyes go?

Answer 35

-Right

Question 36

What two nuclei does the vestibular nucleus interact with?

Answer 36

- Oculomotor nucleus | - Abducens nucleus

Question 37

What is a nystagmus?

Answer 37

- Involuntary shaking to and fro movement of the eyes | - Rhythmic and jerky

Question 38

What are the frequent causes nystagmus?

Answer 38

- Infarction/stroke - MS - Spinocerebellar degeneration - Developmental problems in the pons and cerebellum - Visual problems such as albinism

Question 39

How do you test if you horizontal canal is working properly?

Answer 39

Caloric Nystagmus

Question 40

What is the caloric Nystagmus test?

Answer 40

-Test the horizontal canal with hot or cold water

Question 41

If you put hot water into the right ear in the caloric nystagmus test what way does your eyes turn?

Answer 41

-Left

Question 42

If you put cold water into the right ear in the caloric nystagmus test what way does your eyes turn?

Answer 42

-Right

Question 43

What is the slow phase of the caloric nystagmus test?

Answer 43

-Eyes initial movement

Question 44

What is the fast phase of the caloric nystagmus test?

Answer 44

-Corrective saccade

Question 45

If the slow phase it absent in the caloric nystagmus what area of the pathway is damaged?

Answer 45

- Horizontal canal weakness (ipsilateral) | - Damage to the MLF/Pons

Question 46

If the fast phase is absent from the caloric nystagmus what area is damaged?

Answer 46

-Cerebral damage

Question 47

If both phases are absent/lost from the caloric nystagmus test what is damaged?

Answer 47

-Bilateral hindbrain

Question 48

If the person has vertigo problems where the patient says "I'm spinning" what is damaged?

Answer 48

-Vestibular system

Question 49

If the person says "WOAH, the room is spinning" what is damaged?

Answer 49

-Central vestibular issue