GLOSSARY

The semicircular canals are three ring-shaped tubes filled with endolymph in the inner ear, lying roughly at right angles to one another and detecting rotational (angular) acceleration of the head in three spatial planes.

Components and Directions

• Anterior (superior) canal: forward and backward head movement (such as nodding “yes”) and tilting.
• Posterior canal: forward and backward movement and side-to-side tilting.
• Lateral (horizontal) canal: turning the head left and right (such as shaking the head “no”).

Mechanism