Vestibular

Question 1

Inner Ear
Vascular structures

Answer 1

anterior inferior cerebellar artery

Question 2

Branch of anterior inferior cerebellar artery:

Answer 2

internal auditory artery

Question 3

Internal auditory artery separates into

Answer 3

Vestibular a.
Cochlear a.

Question 4

Vestibular apparatus is made up of:

Answer 4

Utricle
Saccule
Semicircular canals

Question 5

Stereocilia function

Answer 5

helps us hear and convert sound waves

Question 6

Where can you find Perilymph?

Answer 6

Cochlea

Question 7

Where can you find endolymph?

Answer 7

Semicircular canal

Question 8

Conduction hearing loss

Answer 8

Impacted ear wax
Middle ear damage

Question 9

Sensorineural hearing loss

Answer 9

Damage to hair cells of organ of corti
Damage to processes of cochlear division CN VIII
Congenital: most genetic

Question 10

Congenital sensory nerve deafness is typically a

Answer 10

recessive trait

Question 11

Common causes of conduction deafness may include:

Answer 11

Otosclerosis
Fluid in the tympanic cavity
Ruptured tympanic membrane

Question 12

Sensorineural deafness results when

Answer 12

the transmission of nerve impulses is impaired.

Question 13

Conduction deafness occurs when

Answer 13

the transmission of sound waves across the tympanic membrane through the ossicles onto the oval window is impaired

Question 14

Vestibular system is essential for

Answer 14

postural control and for the control of eye movements.

Question 15

Vestibular apparatus responsive to:

Answer 15

Position of the head relative to gravity
Head movements

Question 16

how is Vestibular apparatus transduced?

Answer 16

Vestibular nerve
Vestibular nuclei (in the brainstem)
Flocculonodular (flocculus) lobe (smooth out head and eye movements)

Question 17

semicircular canals are sensitive to which acceleration?

Answer 17

Angular acceleration

Question 18

otolithic organs (saccule and utricle) are sensitive to which acceleration?

Answer 18

Linear acceleration in vertical and horizontal planes

Question 19

Deflection toward the kinocilium activates

Answer 19

K+ channels causing depolarization of the synapse

Question 20

Deflection away from the kinocilium

Answer 20

hyperpolarizes the synapse

Question 21

The utricle detects linear accelerations and head-tilts in the

Answer 21

horizontal plane

Question 22

The saccule detects linear accelerations and head-tilts in the

Answer 22

vertical plane

Question 23

Benign Proximal Positional Vertigo (BPPV) cause

Answer 23

otoliths move into ampulla

Question 24

Benign Proximal Positional Vertigo (BPPV) symptoms

Answer 24

will ALWAYS see rotational eye movements

Question 25

Receptors in semicircular canals detect movement of the head by sensing the motion of

Answer 25

endolymph

Question 26

Crista

Answer 26

consists of supporting cells and sensory hair cells

Question 27

cupola

Answer 27

Hair cells are embedded in a gelatinous mass

Question 28

If I turn my head to the R, which side gets depolarized and which side gets hyper polarized?

Answer 28

The R side gets depolarized and the L side gets hyper polarized

Question 29

Saccule and utricle functions

Answer 29

linear acceleration and position of head relative to gravity

Question 30

Projections from the vestibular nuclei contribute to:

Answer 30

Sensory information about head movement and head position relative to gravity Gaze stabilization (i.e., control of eye movements when the head moves) Postural adjustments Autonomic function and consciousness

Question 31

Vestibulo-ocular reflex (VOR)

Answer 31

Stabilizes visual images during head movements. The primary function of the VOR is to control the eye position during head movements so as to maintain a stable visual image and therefore contribute to equilibrium

Question 32

Example of Vestibulo-ocular reflex (VOR). Moving my head to the R

Answer 32

Signals from the right horizontal semicircular canal increase Signals from the left horizontal semicircular canal decrease Signals travel to vestibular nuclei and then CN nuclei Activation of rectus muscles that move eye to the left Inactivation of rectus muscles that move eye to the right

Question 33

Three major planes of action of the vestibulo-ocular reflex

Answer 33

Yaw, Pitch and Roll

Question 34

Yaw

Answer 34

horizontal rotation about the vertical z axis

Question 35

Pitch

Answer 35

vertical rotation about the binaural y axis

Question 36

Roll

Answer 36

vertical rotation about the x axis (“line of sight”).

Question 37

A tone imbalance in yaw indicates lesions of the

Answer 37

lateral medulla, including the root entry zone of the eighth cranial nerve and/or the vestibular nuclei.

Question 38

A tone imbalance in roll indicates

Answer 38

unilateral lesions (ipsiversive at pontomedullary level

Question 39

A tone imbalance in pitch indicates

Answer 39

bilateral (paramedian) lesions or bilateral dysfunction of the cerebellum, especially the flocculus.

Question 40

Vestibular role in motor control, Two roles:

Answer 40

Gaze stabilization and postural adjustments

Question 41

Two spinal tracts of postural adjustments

Answer 41

Lateral vestibulospinal tract and Medial vestibulospinal tract

Question 42

Lateral vestibulospinal tract

Answer 42

Lower motor neurons to postural muscles in the limbs and trunk

Question 43

Medial vestibulospinal tract

Answer 43

Adjust head position to upright

Question 44

Vestibulocerebellum

Answer 44

Receives vestibular information Influence postural muscles and eye movements Can be mapped in the cerebellum

Question 45

Six pathways associated with the vestibular nuclei function

Answer 45

help you stand up tall