vestibular system

Question 1

importance

Answer 1

provides conscious preception of head orientation and positon and sense movement of the body

postural control
controls eye movement

Question 2

transduction

Answer 2

converting tilt, acceleration and velocity into neural signals for the brain

Question 3

utricle and saccule

Answer 3

detect linear acceleration and tilt of head

Question 4

cristae ampullaris

Answer 4

detect rotational acceleartion

Question 5

maculae

Answer 5

receptors that help utricle and saccule

covered with otoconia and otoliths

Question 6

semicircular canals

Answer 6

3 fluid filled rings

to respond to rotational acceleration and deccelaeration of the head

Question 7

crista ampularis

Answer 7

is sensory organ and semicicular canals

Question 8

the signal in the semicricular canal increases on

Answer 8

side head turns

Question 9

pathway in accordance to stimuli: angula acceleration of the head

Answer 9

semicricular canals

into vestibular nuceli and vestibulocerebellum

1- vestibular cerebral cortex= preception of head orientation

2- oculomotor= eye movement

3- spinal cord= postural control

Question 10

pathway in accordance to stimuli: linear acceleartion of head

Answer 10

saccule and utricle

into vestibular nuceli and vestibulocerebellum

1- vestibular cerebral cortex= preception of head orientation

2- oculomotor= eye movement

3- spinal cord= postural control

Question 11

vestibuloccular goes

Answer 11

via MLF to CN 3,4,6

Question 12

vestibulospinal goes

Answer 12

medial and lateral VS tract

Question 13

vestibulocerebellar goes

Answer 13

direct and via lateral vestibular nuclei

Question 14

sensory weighting

Answer 14

sensorimotor system intergrates aff and eff inputs in ventral nervous system which is controlled by

1- feedback control
and
2- feedforward control

Question 15

feedforward control

Answer 15

anticipatory action with a direct descending command
plan to push a heavy door

Question 16

feedback control

Answer 16

cerebellar system regulates the visual, vestibular and somatosensory inputs during the activity

reactive changes to posture

Question 17

vertigo

Answer 17

concious illusion of motion= spinning tilting, moving

Question 18

nystagmus

Answer 18

rapid rhythmic repetitve oscillatory involuntary eye movements

Question 19

oscillopsia

Answer 19

lack of gaze stabilisation- blury vsion

Question 20

lateropulsion

Answer 20

gait leaning or turning to one side

Question 21

gait ataxia

Answer 21

clumsy poorly controlled voluntary movements

Question 22

4 eye movements

Answer 22

saccades
smooth pursuit
vergence
vestibulo-ocular

Question 23

saccades

Answer 23

rapid balistic movement
abrupt changes

Question 24

smooth pursuit

Answer 24

slower tracking movement/ voluntary control

Question 25

vergence

Answer 25

alligns both eyes fovea with objects at distance

Question 26

vestibulo-ocular

Answer 26

stabilise eyes relative to world most effective with rapids head movements

Question 27

vestibular ocular reflex

Answer 27

stabilise visual images on the retina when head is moving activated by vestibular inpt works to prevent visual world bouncing

Question 28

optokenetic reflex

Answer 28

eyes follow a moving stimulus smooth pursuit keeps image stationary once reach their end range eyes jump back with a saccade

Question 29

disorders may affect peripheral strucutres such as

Answer 29

cranial nerves receptors

Question 30

benign paroxysmal positional vertigo

Answer 30

disorders due to dislodged otholiths falling into SCC

Question 31

acute vestibular neuritis

Answer 31

inflammation of vestibular nerve= billat

Question 32

vestibular labyrinthis

Answer 32

inflammation of labyrinth

Question 33

vestibular schwannoma

Answer 33

benign tumour of vestibular nerve

Question 34

benign paroxysmal positional vertigo

Answer 34

due to otoconia dislodge it floats in SCC creates abnormal CN8 signal