Vestibular system

Question 1

What are the vestibular sensory organs?

Answer 1

Otolith organs (Utricle and saccule) and semicircular canals

Question 2

What is the function of the otolith organs?

Answer 2

Detect linear acceleration of the head, and position with respect to gravity. Signals postural changes

Question 3

What is the function of the semicircular canals?

Answer 3

Detect angular acceleration of the head

Horizontal canal –> horizontal rotation

Posterior and anterior canals –> vertical rotation

Question 4

How does the vestibular system communicate motion information?

Answer 4

head rotation –> movement of endolymph within semicircular canal –> endolymph moves in opposite direction –> deflection of cupula –> change in hair cell potential

Question 5

What function does the vestibuloocular reflex serve?

Answer 5

provides stable visual field during head movement via oculomotor nuclei in brainstem. Dysfunction –> nystagmus