Vestibular transduction

With vestibular transduction, “vestibular” refers to balance, and transduction refers to the process by which the ear converts specific head movements into electric impulses, so that we can interpret where we are in space.

The ear is made up of three parts: the outer ear, the middle ear, and the inner ear.

The first part is the outer ear which is the part you see and hang earrings on, called the pinna, as well as the ear canal.

The second part is the middle ear, which is a tiny chamber that houses even tinier ear bones—the malleus, incus, and stapes.

The outer and middle ear only play a role in hearing - however, the third part, the inner ear, deals with both hearing and balance.

On the outside, the inner ear has a tough bony shell - the bony labyrinth; and inside the bony labyrinth, there is the membranous labyrinth.

Now, both of these sections are filled with fluid - the bony labyrinth contains a fluid called perilymph, while the membranous labyrinth contains endolymph.

The bony and membranous labyrinth make up the structure of all three parts of the inner ear.

The first is the vestibule, which is like a hallway that leads up to two other parts or rooms - the cochlea, towards the front of our head, that deals with hearing, and a second room containing the three semicircular canals, towards the back.

The semicircular canals, along with two other structures - the utricle and saccule, which are located in the vestibule - make up the vestibular apparatus, that helps us detect changes in our static and dynamic equilibrium.

Our static equilibrium is a job for the utricle and saccule - also known as the otolith organs. They contain endolymph, as well as special balance receptors that detect changes in our head position in relation to horizontal or vertical acceleration.