What Is The Working Of Ear?

The ear is a wonderful instrument is our body. We do not have to “tune”. Even the tiny ticks of watch it picks up. the process of hearing begins with sound. It is not only the ear with which we need to be able to hear. “Sound waves” are what the waves of air are, and strike on the eardrum. We cannot see or feel these waves. Our ear is so delicate that it catches the slightest vibration and passes on to the brain. We hear only, when such waves reach the brain.

The air is made up of three parts: an outer ear, a middle ear and an inner ear. Some animals can move their outer ear forward in order to catch the sound more effectively. We cannot move our outer ear, so it does no really help us much in hearing.

The sound waves on entering the outer ear, travel down a, canal. There is a thin skin at the end of this canal. This skin is tightly stretched across a tube. This skin separates the outer ear and the middle ear, while acting as a drum membrane. From the inner side of this drum a short tube, called the “Eustachian tube” leads to the throat. Enough air enters the tube through throat; the pressure carried by the vibrations on the other side of the drum is equalized. Otherwise, there are chances that the membrane might be broken by loud sounds.

Directly behind, or, on the other ride of the drum membrane in the middle ear are strung three curious little bones like the “hammer”, the “anvil”, and the stirrup. They touch both the drum membrane and the inner ear. When the sound waves strike the membrane, they start the three bones vibrating.

These bones, further, setup a series of vibrations in the fluid of the shell shaped inner ear. In this shell, called the “cochlea”, tiny cells transfer the sound to certain nerves. There nerves send them to the brain, which recognises them. It is this recognition, that we call “hearing”.

In the inner ear too, there are three semicircular canals. These have nothing to do with hearing. They are also filled with fluid, and they give us our sense of balance. If they are out of order, we become dizzy and cannot walk straight upright.