The ear comprises of many parts and all of these parts need to all be functioning to give a person one of their senses – hearing. Parts of the ear also help with balance and body positioning.
The ear is split into three parts – the outer ear, the middle ear and the inner ear.
The outer ear is the parts that you can see – the pinna is the fleshy ear part on the side of your head and this collects the sound waves and directs them down the auditory canal and make the ear drum (tympanic membrane) vibrate.
The middle ear is made up of three tiny bones in a hollow air filled space – the hammer, anvil and stirrup (or the malleus, incus and stapes) these work by continuing and amplifying the vibrations from the ear drum onwards to the inner ear. Their primary function is to transfer the sound waves in the air into waves in the liquid found in the cochlear. These bones are only a couple of millimetres wide each. The tiniest muscles found in your body are here attached to the bones.
The inner ear comprises of the cochlear and the semicircular canals. These are both filled with fluid. The semicircular canals send messages to the brain with regards the balance and position of the head/body. As you move the fluid constantly levels out and this is recorded and a message sent to the brain. The cochlear is about the size of your little finger nail. This is like a hollow coiled shell filled with fluid and tiny little hairs. The coils go round 2 and 2/3 times. The vibrations in the fluid cause the hairs to move, these hairs trigger an electrical impulse down a small nerve to the auditory nerve which then carries this message to the brain. The brain then translates this electrical impulse into its own interpretation of noise. The higher sounds are picked up at the beginning of the cochlear and the lower pitch sounds are picked up further down into the coiled structure.
The eustachian tube is connected to the nasal cavities and helps to regulate the air pressure in the middle ear. Most people notice pressure in the ear when they have a cold or are in an aeroplane and swallowing or blowing your nose helps to relieve this pressure.
As there are many parts of the ear, there are lots of things that can go wrong! These are a small list of examples:
- The hair cells in the cochlear can break, become deformed and stop working in many ways (this is what has happened to me but we don’t know the cause)
- The middle ear bones can fuse or simply be missing
- The ear drum can rupture
- The middle ear becomes full of fluid
- Wax build up, pressure changes, exposure to loud noises and the ageing process can all alter the ear function
It depends on where the defective part of the ear is as the type of deafness this causes. Conductive deafness is where sound cannot pass through the outer or middle ear. Sensorineural deafness is where the cause of the deafness is in the cochlea or in the auditory nerve. This type of deafness often reduces the quality of sound as well as its volume.
Rainbow Ears 