The human ear is divided into three parts leading up to the brain – the outer ear, middle ear and the inner ear.
The outer ear consists of the pinna (external ear), ear canal and eardrum. Sound is collected by the pinna which directs the sound down the ear canal, striking the eardrum and causing it to move or vibrate.
The middle ear is a space behind the eardrum that contains the three smallest bones in our body: malleus, incus and stapes. This chain of tiny bones is connected to the eardrum at one end and to an opening to the inner ear at the other end, referred to as the oval window. Vibrations from the eardrum cause these bones to vibrate which, in turn, creates movement of the fluid in the inner ear.
Movement of the fluid in the inner ear, or cochlea, cause tiny structures called hair cells to actively sway. This movement of the hair cells sends electric signals from the inner ear up the auditory nerve (also known as the hearing nerve) to the brain.
The brain then interprets these electrical signals as sound.
The inner ear is also responsible for our balance. The semicircular canals are three tiny, fluid-filled tubes in your inner ear that help you keep your balance.