Vestibular System

Anatomy

100

The structures that make up the labyrinth

3 Semicircular canals

2 otolith organs

200

cristae are found within the

semicircular canals

300

When the head turns, endolymph in duct bends the _____ – this distorts hair cells, which generates action potentials.

cupula

400

these bundle to become the vestibular nerve

hair cells/ cilia 

500

when the vestibular nerve leaves the inner ear, it travels to the ______ to synapse with second order neurons

vestibular nuclear complex

Terminology

100

nystagmus

• Rhythmic combination of these normal involuntary vestibulo-ocular movements:

• Slow movement of eye from center to left (or right)

• Sudden quick jerk of eye back to center

200

this type of acceleration is when force is applied to an object that moves in a line, like stopping in a car or falling down

Linear acceleration

300

The fluid in the semicircular canals is called

endolymph

400

the sensory apparatus throughout the utricle and the sacculus

Macula

500

The three semicircular canals detect head movements of: left/right, nose up/down, ears up/down which are also known as

Yaw, Pitch, and Roll

Function

100

detect rotational acceleration

semicircular canals

200

detects linear acceleration

vestibule

300

This brain region receives input from the vestibular system and adjusts to motor movements

Cerebellum

400

Reflexive control of horizontal and vertical eye movement, which compensates for head movement. 

vestibular-ocular reflex

500

Projections from this brain region are sent to the cerebral cortex and are thought to provide the conscious perception of body position and acceleration

Ventroposterior (VP) Thalamus