Vestibular Physiology Flashcards
What are the two key components of the vestibular system?
Semicircular canals
Otolith organs
How many semicircular canals are there on each side of the head?
3
What do the semicircular canals detect?
Head rotation
Which semicircular canal(s) detects yaw rotation of the head?
Horiztonal
Which semicircular canal(s) detects pitch and roll rotation of the head?
Superior and posterior
How does is the membrane potential affected by the stereocilia moving towards the kinocilium?
Depolarisation
How does is the membrane potential affected by the stereocilia moving away from the kinocilium?
Hyperpolarisation
Name the otolith organs
Utricle
Saccule
What is the orientation of the saccule and which movement axis does it detect?
Vertical
Up/down and forwards/backwards
What is the orientation of the utricle and which movement axis does it detect?
Horizontal
Left-right and forwards/backwards
What is the effect on membrane potential of cilia orientated towards the striola in the utricle?
Depolarisation
What is the effect on membrane potential of cilia orientated towards the striola in the saccule?
Hyperpolarisation
What do the semicircular canals detect?
Rotation
What do the otolith organs detect?
Linear acceleration
Where does cranial nerve VII project to with regards to vestibular function?
Vestibular nuclei complex - in brainstem
