https://www.youtube.com/watch?v=1AZnFszUroI&t=63s

https://slideplayer.com/slide/7914330/

https://slideplayer.com/slide/7411968/

D. Merfeld, in Encyclopedia of Neuroscience, 2009

The semicircular canals respond to head rotation but have a limited dynamic range; the otolith organs respond equivalently to both gravity (‘tilt’) and linear acceleration (‘translation’)....nervous system combines visual, vestibular, and other cues to yield estimates of tilt, translation, and rotation...combined information from the semicircular canals and otolith organs typically yields more accurate estimates of motion and orientation than would be attained via either sensory modality alone.

3 translational movements

3 rotational

The outer and middle ear are involved with hearing

The inner ear functions in both hearing and equilibrium

Receptors for hearing and balance:

Respond to separate stimuli

Are activated independently

Problems with the vestibular system can lead to peculiar sensations:

Spatial Disorientation: Any impairment of spatial orientation (i.e., our sense of linear motion, angular motion, or tilt)

Dizziness: Nonspecific spatial disorientation

Vertigo: A sensation of rotation or spinning

Imbalance

Blurred vision

Illusory self-motion

Vestibular organs: The set of five organs—three semicircular canals and two otolith organs

Where am I going?

Which way is up?

head motion

self position 

spatial orientation in regards to gravity

Linear motion

Angular motion

Tilt

Allow for the vestibulo-ocular reflex VOR: Stabilizes visual input by counter rotating the eyes to compensate for head movement