Final -Ch. 22 - Vestibular System

Question 1

Job of vestibular system?

Answer 1

Fxns to keep us visually and physically steady in world.

Question 2

Gaze stabilization is what reflex?

Answer 2

VOR

Question 3

What is the vestibulospinal tract?

Answer 3

LMN - keeps us upright against gravity

low level of control

located to BS

Question 4

Which is the conscious relay pathway?

Answer 4

cerebrocortex

Question 5

Where do the autonomic function and conciousnous have connection to and what do problems in homeostasis indicate?

Answer 5

reticular formation

homeostasis

Question 6

What are the two parts of Cranial N VIII and what do each do?

Answer 6

cochlea - hearing

vestibular - balance

Question 7

Describe the location and motion detected by 3 semi-circle canals.

Answer 7

anterior - 45 degrees off centered -

posterior - 45 degrees off-centered -

horizontal - lateral, a bit tilted -

Question 8

What is located at end of canals and what does it contain?

Answer 8

ampula

hair follicles

Question 9

What reflex occurs when head is moving but object is not?

Answer 9

optokinetic reflex

smooth pursuits

Question 10

What is a nystagmus?

Answer 10

fast reset for eyes to detect new object

Question 11

Where does the pathway from cranial N VIII end?

Answer 11

pons and medulla jx

Question 12

What are the 5 systems the vestibular Nuclei recipe information from?

Answer 12

vestibular 
vision
proprioception
tactile
auditory information

Question 13

Where does the vestibular nuclei send information so equilibrium is conscious and confirmed?

Answer 13

cerebral cortex

Question 14

Which two cortexes are reciprocally inhibitory?

Answer 14

vestibular and visual

Question 15

What is Pusher’s syndrome?

Answer 15

PATHWAYS FROM INNER EAR TO CORTEX GET DAMAGED – PT FEELS LIKE THAY ARE FALLING OVER AND WHEN THEY TRY TO PUSH THEMSELVES BACK TO ALIGHNMENT THEY ARE ACTUALLY PUSHING SELF OVER

Question 16

What are the two vestibular systems we are focusing on?

Answer 16

peripheral - semi-circles and otoliths

Cranial N

Question 17

What are the two vestibular systems we are focusing on?

Answer 17

peripheral - semi-circles and otoliths

Cranial N

Question 18

feeling of movement without it (spinning)

Answer 18

vertigo

Question 19

What are the S&S of vestibular dysfx?

Answer 19

nausea and vomiting

Question 20

dyesequillibrium - impaired gaze stabilization

Answer 20

VOR is not working, could work in one and not the other

blurry

Question 21

Oscillopsia

Answer 21

completes lack of gaze stabilization

complete lack of VOR

Question 22

Unilateral hyperfunction

unilateral / peripheral

one side too excited

Answer 22

one side is more active than it should be

BPPV

sends signals of moving even when I am still

dizziness and nausea 
esp. vertigo
postural instability but stays put
reduced gaze stabilization - pathologic
VOR temporarily broken

Question 23

Unilateral Hypofunction

unilateral / peripheral

Answer 23

vestibular neuritis - squeezing Cranial N VIII

one side, night-night

just standing still - fewer signals

sneaks up

BLURRINESS
FEELING LIKE FALLING

gaze instability - absent VOR (eyes move with head)
postural instability - impaired VOR and reduced vestibulospinal (lateral vestibulospinal) activity
vertigo? no
nausea? no

Question 24

What is oscillopsia? What can cause bilateral oscillopsia?

Answer 24

no gaze stabilization
Cranial N VII both sides
NO VOR at all

medications - ototoxic