“You better turn down the volume on your headphones before you go deaf!” Do you remember your parents telling you this?
The ear is one of our most valuable sense organs. It connects us to the world and leads our everyday lives without limitations. Although we may not be mindful of it, the ear is always hard at work, even when we are asleep. The ear is not just a hearing organ. It is a complex system of parts that not only enables us to hear but also helps us to maintain our balance when we are walking or running. I never paid much attention to my ears until I had an ear infection. It all started with a cold. A few days after, I experienced ear pain and had trouble hearing. It was when I went to a doctor that I realised I had an infection of the middle ear, which made it difficult for me to hear. It was at that moment, I realised I had taken my gift of hearing for granted.
Let’s try a simple activity and you will understand why we should start appreciating our ears more. All you need is a blindfold, a quiet room and a friend to be your guide. Stand about 1.5 metres away from a wall, put the blindfold on and start walking as you snap your fingers. As you walk closer to the wall, listen carefully to the echoes created when you snap your fingers. Finally, ask your guide to stop you if you are too close to the wall. You do not want to get hurt by walking into it!
Aren’t our ears amazing? You can gauge how close you are to the wall by listening to the echoes created when you snap your fingers while walking. This is because we can perceive objects in the environment by sensing echoes from surrounding objects. This is also known as human echolocation.
How do we hear?
- Sound waves hit the outer ear (1) and travel to the eardrum (8).
- The eardrum vibrates, causing the three tiny bones in the middle ear (2, 3, 4) to move.
- This movement causes the fluid in the cochlea (6) to vibrate.
- This causes the hair cells in the cochlea to bend, producing electrical signals.
- The auditory nerve (5) then carries this electrical signal to the brain, which turns it into a sound that we recognise and understand.
Noise-induced hearing loss
Noise-induced hearing loss is caused by long and repeated exposure to sounds at or above 85 decibels. As you may notice, after leaving a very noisy place such as a concert, you may not hear as well as before. You may also experience some ringing in your ears. These are indications that the sounds are too loud for your ears.
On average, a person is born with about 16,000 hair cells within their cochlea. These cells allow your brain to detect sounds. Listening to loud sounds over a long period can overwork the hair cells in the inner ear, causing them to die. Injury to the inner ear is generally permanent.
Music is widely enjoyed by many around the world. As an avid music lover, music is part of my everyday life. It is worrying to know that some studies have found that Singaporeans may lose their hearing as early as their 40s due to prolonged exposure to loud music.
Although noise-induced hearing loss is permanent, it is preventable. Let us take a closer look at how we can care for our ears:
The ear is extremely powerful but also extremely delicate. By the time you notice hearing loss, many hair cells may have been destroyed and cannot be repaired. Although there is no way to reverse noise-induced hearing loss, it is preventable. Do not wait until it is too late to start taking care of your ears. Start caring for your ears now by paying more attention to your hearing health!
Written by Michelle Ng
Illustrated by Toh Bee Suan