Vestibular Function

Question 0

Perilymph

Answer 0

Bathes the basolateral membrane of hair cells; resembles CSF

*high Na+; low K+

Question 1

Endolymph

Answer 1

Bathesapical surface of hair cell; resembles cytoplasm

-high K+; low Na+

Question 2

NT released by hair cells

Answer 2

Glutamate

-Is constantly released producing a tonic state; influx of Ca2+ increases release

Question 3

Linear Acceleration

Answer 3

Detected by the utricle (horizontal plane)

and saccule (vertical plane)

Question 4

Rotational Acceleration

Answer 4

Detected by semicircular canals

Question 5

Striola

Answer 5

Dividing line of the maculae where hair cells are oriented towards

Question 6

HVOR

Answer 6

Fast reflex that moves eyes in OPPOSITE direction of the rotation of the head

-Is fast because there are few synapses and neuronal pathway is short

Question 7

Caloric testing

Answer 7

Warm H20 causes endolymph to rise and increase neuronal firing rate =>Eyes move towards same ear

Cold H20 causes endolymph to fall and decrease neuronal firing rate
=>Eyes move towards opposite ear

*COWS

Question 8

Barany Chair Testing

Answer 8

Nystagmus first observed; followed by normal sight
-endolymph and head reach the same rotational velocity

-Postrotatory nystagmus is observed when chair is stopped