The anatomy of hearing and what happens when you damage it

Your ears let you hear all that’s around you; whether it’s music, voice, or just the birds tweeting outside your window. So how can you go about protecting them? Is there anything that you should or shouldn't do? We sat down with Paul Checkley, audiological scientist at Harley Street Hearing, and Wendy Davies, head of audiology at Siemens Hearing Instruments to find out the main dos and don'ts.

“The best way to protect your ears is either to ensure that you do not expose your ears to high levels of noise or to use hearing protection when you are in noisy environments,” says Checkley starting the ball rolling. Davies adds that if you’re worried there are plenty of places you can go to get it checked out:

“If you notice changes in your own hearing or in someone you know, a hearing test should be sought immediately. Visit your GP who will refer you to an audiologist if necessary and rule out any medical conditions first. High street dispensers in your local town will also offer a hearing check service.

“The quicker hearing impairment is detected, the quicker a solution can be achieved. Otherwise, a hearing test is recommended every 3 years; however anyone regularly exposed to hazardous noise should have an annual hearing test or ‘audiogram’ as it is properly known.”

Checking is one thing, but what about basic protection when your ears are out and about?

“General day-to-day activity will not cause any problems but if you are going somewhere excessively noisy, such as a rock concert, ear protection should be worn. Ear protection is also advisable when using any household and garden power tools,” says Davies.

But before you read that to mean mowing the lawn or hoovering the living room, Checkley says that “as long as you are vigilant when levels are high you should not become over concerned to the point where avoiding noise affects your day-to-day life".

So can you damage your ears by listening to music on your headphones too loudly?

“Yes,” says Checkley. “It is possible to damage your hearing by listening to MP3 players. As long as the volume is kept to a comfortable (not loud) level there is not a problem. If other people can hear your headphones it is likely that you have the volume too high.”

“Many people do not realise the damage that can be done if you listen to music at a high volume (classified as over 80 decibels),” says Davies. “This is similar to the sound level of standing at the side of a very busy road. Volumes through headsets or ear phones intensify and can easily reach 110-120 decibels.”

A normal conversation is 60-65 decibels, while a Pneumatic (jack) hammer is between 120 - 130 decibels. Standing on a runway next to a jet engine will blast your ears with over 150 decibels.

“Generally, it is safe to listen to an MP3 player or iPod for about an hour at time as long as it is at a sensible volume.  It is also advisable to take a 5-minute rest every hour to allow your ears to recover,” says Davies.

One thing that you shouldn’t do, and both our experts agree, is clean out your ears with cotton buds to help you hear better.

“You shouldn’t put anything smaller than your elbow in your ear, which means no cotton buds,” says Davies. “Cotton buds may push wax further into your ear canal causing it to impact into a hard plug, which has to be removed by a nurse or doctor. It is also possible to scratch your ear canal with a cotton bud, which will make it very sore and could lead to infection. The worst case scenario would be pushing the cotton bud through your ear drum, which would not only be extremely painful, but again cause hearing loss. The best way to clean ears is with a tissue or flannel just as far as you can get your finger in.”

If you’re not damaging your ears with cotton wall buds there are plenty of noises that can do the job for you. So, is it short loud noises or longer exposure that can do the worst damage?

“It is a mixture of the two. Quieter sounds are damaging if you are exposed to them for a longer time. If the sound is very loud, one momentary blast (like an explosion or a gunshot) can be very damaging,” says Checkley, before adding that the most common cause of hearing loss is presbycusis or age related hearing loss. “This is a mixture of a number of issues including genetic causes, noise damage, diet etc.”

If it’s not old age it’s certainly going to be “noise from gunfire or from people working in a very noisy environment,” says Davies.

“Taking the example of listening to a loud iPod on a regular basis; sound waves from the music travel into the ear canal where they hit the eardrum and make it vibrate,” comments Davies. “These vibrations pass to three small bones (the hammer, anvil and stirrup) in the middle ear and continue to the inner ear.”

“The structures damaged by noise are the hair cells in the cochlea. That means the sensory cells, which are responsible for sending the sound impulses to the brain, do not function properly,” adds Checkley.

So can we train our hearing to be better?

“There is some evidence that when we have hearing loss and start to wear a hearing aid our auditory system re-configures to process the new sound from the hearing aid more effectively. The auditory system is quite "malleable" particularly when we are younger and can therefore be "trained" to receive different inputs more effectively,” says Checkly.

“You can’t improve your hearing thresholds but you can improve your listening skills and use tactics such as looking at people who are speaking to you to gain additional information from their gestures and body language,” says Davies.

So is there any technology or procedures that can repair damage to hearing?

Checkley has some bad news:

“No, there is nothing that can repair damage to the organ of hearing  - it is permanent and irreversible. Modern technology means that hearing instruments are more effective than ever before but they are not able to restore hearing,” meaning you’ve got to take really good care of those funny looking things stuck to the side of your head. You’re going to need them for a rather long time to come.

For more on how to look after your ears and some recommended headphones that'll help do the job for you, check out Etymotic and the ER 4 MicroPro series

- CREDIT: Anatomy of the ear - Chittka L, Brockmann