The Vestibular System

Question 1

Recognise that vestibular hair cells use the same cellular mechanism of mechanoelectrical transduction as auditory hair cells

Answer 1

both convert mechanical stimuli into electrical signals
i.e. bending of stereocilia in response to mechanical forces

The bending of stereocilia opens mechanotransduction channels, which allow ions to flow into the hair cell and depolarize it.

This depolarization triggers the release of neurotransmitters at the synapse between the hair cell and the vestibular or auditory nerve fibres, which ultimately leads to the transmission of signals to the brain.

Question 2

Explain the purpose of the vestibulo-ocular reflex

Answer 2

A reflex that allows us to maintain stable vision during head movements. When the head moves, the eyes must move in the opposite direction to keep the visual image stable on the retina

Vestibular nystagmus enables the resetting of eye position during sustained head rotation