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Deaf Is.. The Ear

There are many different ways that people become deaf. Some people are born deaf because it runs in the family. Other people are born deaf without a specific reason. Another way people become deaf is they become sick. For example, spinal meningitis and other viruses cause high fever. When you get a very high fever, it can damage your inner ear. Some people lose their hearing because of accidents. Being around very loud noises can damage your hearing too. Have you noticed many rock stars perform with earmolds in their ears? That’s to protect their hearing! And people also lose their hearing as they get older.

This is an audiogram. When you get a hearing test, what you can and cannot hear is plotted on it.

audiogram

Normal Hearing 0 dB to 15 dB

Mild Loss 16 dB to 35 dB

Moderate 36 dB to 50 dB

Moderate/Severe 51 dB to 70 dB

Severe Loss 71 dB to 90 dB

Profound 91 dB or more

Learn More About the Ear

The Ear - Hearing

earYour outer ear is shaped just right to catch sounds. These sounds are called 'sound waves'. They travel into your ear and down the tube called the "ear canal". Now the sound waves are in your middle ear.

eardrumStretched over the end of the ear canal is the eardrum. The sound waves bounce onto the eardrum, making it move back and forth, or vibrate.

ear bonesThe three smallest bones in your body, the malleus, stapes and incus, are attached to the eardrum. When the eardrum moves, it makes these tiny bones move too. They continue to move the sound to your inner ear.

cochleaThe inner ear has the cochlea. Cochlea is Greek for 'snail', which is exactly what it looks like - a snail’s shell. The cochlea is about the same size as a pea. This is where you 'hear' different sounds.

cochlea tubesThere are three 'tubes' in the cochlea. The top and bottom canals protect the middle canal. The middle canal is where the sound is heard.

When these little hairs are touched, they bend. The sound wave becomes a message that goes from the 8th nerve to your brain. The 8th nerve takes the message (the sound) to your brain. The brain then 'tells' you that you've heard something.

cochlea Each tiny hair in the cochlea sends a different sound message to the brain. When all the hairs are 'working' properly, then the brain gets all the right sound information and your hearing is fine.

But sometimes the hairs in the cochlea don't work. Maybe they're damaged because of an accident or severe illness. Then the sound messages can't travel to the brain.