Vestibular System

Question 1

Describe the vestibulo-ocular reflex (VOR)

Question 2

What are the tests in the VNG battery?

Question 3

How are vertical eye movements recorded?

Question 4

How are horizontal eye movements recorded?

Question 5

How is nystagmus recorded?

Question 6

What is the role of the vestibular system in balance maintenance?

Question 7

T/F: The maculae contain otoconia

Answer 7

True

Question 8

T/F: Type I hair cells are only in the cristae

Answer 8

False - both the maculae and cristae

Question 9

T/F: The crista contain cupola

Answer 9

True

Question 10

T/F: Supporting cells are in the maculae and cristae

Answer 10

True

Question 11

T/F: the cristae respond to gravity

Answer 11

False - maculae responds to gravity

Question 12

T/F: the maculae responds to head tilts (being in tilted position, not tilting motion)

Answer 12

True

Question 13

T/F: the maculae responds to head turns

Answer 13

False - crista responds to head turns

Question 14

When the __________ canal is excited, the _____________ canal is inhibited

Answer 14

right anterior
left posterior

Question 15

Eye movements are innervated by which cranial nerves?

Answer 15

CN III
CN IV
CN VI
CN V

Question 16

Where is CN III located?

Answer 16

midbrain

Question 17

Where is CN VI located?

Answer 17

pons

Question 18

Where is CN VIII located?

Answer 18

Pons, Medulla

Question 19

What information is integrated for balance?

Answer 19

1. Vestibular system
2. Visual input
3. Somatosensory receptors
4. Hearing

Question 20

What is the purpose of VOR?

Answer 20

Maintain a gaze on a fixed target while the head moves. The eyes move in the opposite direction of the head movement.

Question 21

If one’s right vestibular organ stops working, when the person tries to stand straight, what will happen?

Answer 21

Lean or fall to the right

Question 22

If one’s right vestibular organ stops working, what will you observe re: eye movements?

Answer 22

Left beating nystagmus
Eyes will pull to the right since the slow phase moves toward the vestibular system that is weak/affected

Question 23

How is eye position graphed?

Answer 23

jagged lines

Question 24

How is eye velocity graphed?

Answer 24

dots

Question 25

T/F: Eye velocity is calculated for the fast phase

Answer 25

False - eye velocity is calculated for the SLOW PHASE

Question 26

Describe an optokinetic test

Answer 26

A series of dots or the entire visual field moving across the front of the testee

Question 27

Describe a saccade test

Answer 27

A dot jumps randomly. Testee needs to follow with their eyes.

Question 28

Descrive a gaze test

Answer 28

Dot stays still; testee stares at it

Question 29

Describe spontaneous nystagmus test

Answer 29

Vision is denied

Question 30

Describe smooth pursuit test

Answer 30

Dot moves back and forth

Question 31

Describe a positionAL test

Answer 31

Static Examines effect of gravity on specific head orientation Nonlocalizing finding on its own

Question 32

Describe a positionING test

Answer 32

Dynamic Examines effect of a specific head movement Identifies BPPV

Question 33

Which direction should you expect with right warm irrigation?

Answer 33

Right beating nystagmus

Question 34

Which direction should you expect left warm irrigation?

Answer 34

Left beating nystagmus

Question 35

Which direction should you expect right cool irrigation?

Answer 35

Left beating nystagmus

Question 36

Which direction would you expect left cool irrigation?

Answer 36

Right beating nystagmus

Question 37

Provide two examples of symptoms (sensations) that a patient with a peripheral pathology is most likely to present

Answer 37

1. Vertigo after head position changes 2.

Question 38

Provide two examples of symptoms (sensations) that a patient with a central pathology is most likely to present

Answer 38

1. Abnormal smooth pursuit (jagged eye movements; not smooth) 2. Nystagmus remains when trying to fixate on an object (cannot suppress nystagmus)

Question 39

Name two tests of VOR functions

Answer 39

1. Rotational chair 2.