IN OUR series on amazing facts about your body, it is time to turn to a body part which you cannot actually see on yourself, only in a mirror or a photo.
Yep – it’s your ears!
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No matter how far you turn your head or move your eyes you can’t actually see them.
You use your ears on a daily basis, but have you ever stopped to think about how they can be involved in seemingly unrelated processes – like maintaining your balance, experiencing motion sickness and even eating?
From whether you actually need to clean your ears to why some people’s earwax is grey, here are 12 facts you didn’t know about your own ears.
1. Do your ears keep growing?
The outside of the ear is only part of the auditory system, which is divided into the outer, middle and inner ear.
Read more from Dr Philippa
The part you see on the outside has a medical term, called the pinna.
It’s a common myth that your ears keep growing throughout your life.
Once you hit adulthood and stop growing your ears do stop growing but like other body parts, they can – and do – change with age.
Your ears are made of cartilage and skin and the combination of the effects of ageing and gravity essentially mean that your earlobes begin to sag, giving the impression that they are growing.
Add to that, the loss of fullness in the face in the cheeks and lips means that the relative proportions of the face and ears change, but your ears don’t grow!
2. Some people can wiggle their ears
If you watch a cat they often seem to be moving their ears, trying to focus and pay attention to sounds.
The role of the pinna, the external ear in humans, is to collect sound waves in the air and direct them into the external ear canal.
Not all humans can move their ears but some can and this may be a hangover from when it was required.
Now we mostly look at something if we’re paying attention to it – whereas some animals can continue eating while focusing their attention on sounds.
Having two ears helps you work out where sounds are coming from.
3. Your ears don’t actually hear
As we discussed earlier in the series your eyes receive light but it is your brain which translates that information into an image.
So too the ear collects sound waves, but it is the brain which translates that information into sound.
The sound waves travel at about 760 mph, from the external ear canal into the tympanic membrane, the eardrum at the end of the canal.
These sound waves make your eardrum vibrate. This activates the tiny bones in the middle ear and sends the sound waves to the inner ear, the cochlea.
The cochlea is shaped rather like a snail and contains thousands of tiny hair cells which move with the vibrations of sound waves and send the information along the vestibulocochlear nerve to the auditory centre in the brain, which then translates them into the sound you hear.
4. Your body contains a hammer and anvil
It does! But not perhaps the size of the hammer in the toolbox in the back of a cupboard somewhere.
The ossicles are tiny bones found in the middle ear, these are the smallest bones in the human body.
There are three ossicles which are named in Latin for their shapes: the malleus, meaning hammer, the incus , meaning anvil, and the stapes – meaning stirrup, like a stirrup when riding a horse.
This last occisle, the stapes, attaches to the oval window which is the connection between the middle and inner ear.
These bones are tiny: the malleus is approximately 8mm high and 2.7mm wide, the incus just under 7mm high and about 5mm wide and the smallest of them all, the stapes is about 3.5mm tall and 2.4mm wide.
5. How low can you go?
The human ear can detect sound waves as low as 20Hz up to about 20 000 Hz.
Hearing loss can occur at any age and it can take even one single exposure of very loud noise, of over 120 decibels to permanently damage your hearing.
To put this into perspective, normal human conversation is approximately 60dB and a whisper about 30dB. Regular exposure to loud noise can damage hearing over time, so protect your ears from loud music and at work if appropriate.
Even the sound of a lawnmower (80-85dB) can cause issues depending on how long you are exposed to the noise.
Ringing in your ears after a loud concert or sports event is a sign that you are damaging your ears!
6. Don’t put anything smaller than your elbow in your ear
This was a phrase I heard during medical school and still use, ‘don’t put anything smaller than your elbow in your ear’ – and you can’t actually put your elbow in your ear, so leave them alone!
Ears are self cleaning, you do not need to clean out ear wax with a cotton bud and actually using a cotton bud, even if it removes some wax, actually compacts and impacts wax further into the canal, worsening an issue. Leave your ears be!
If you see wax on the outer ear this can be removed.
7. Wax isn’t dirty
The ear canal has glands which produce a waxy substance called cerumen, also known as earwax.
Ear wax isn’t dirty, it is part of how the ear cleans itself and traps dust and other forms of dirt, bacteria etc so that they cannot damage the ear.
Ear wax also helps protect the ear canal when you are submerged in water as water gets into the ear canals.
Too much wax can be a problem though, it can dry and harden and block the ear canal, affecting hearing.
Wax softening drops are available over the counter. If these aren’t sufficient then microsuctioning can remove wax.
8. Wax comes in different colours and textures
Some people have yellow sticky wax and others dryer white/grey ear wax and this seems to be genetic.
The gene responsible for this was found in 2006 in Japan.
Yellow sticky wax is more common in people of Caucasian and African descent while grey/white wax is more common in people of East Asian descent.
Anthropologists have even used ear wax to track the migration of humans!
9. Your ears are involved in balance
The eighth cranial nerve is called the vestibulocochlear nerve. The cochlear part of the nerve is responsible for hearing, while the vestibular part is involved in balance.
The vestibular system is found in the inner ear and includes three loops, called semicircular canals.
These semicircular canals are filled with fluid which moves as you move your head, and signals are sent via the vestibular nerve to the brain.
Balance also relies on information from your vision and proprioception, which is related to the sensation of movement in the skin, joints and muscle – after all, even with your eyes shut you know where your body is in space, if you are sitting or standing.
10. Motion sickness involves your ears!
When there is a mismatch between the signals being received into the brain from these three areas, for example when you are sitting on a boat and telling your brain you are sitting down, but your ear tells you you are moving up and down on the waves and your eyes may give another signal, it results in motion sickness.
So motion sickness actually comes from your ears, even though you bring up the contents of your stomach!
11. The ear never sleeps
In the same way that you ‘see’, or rather your optic nerve sends information to your brain when your eyes are shut or you are sleeping, you never stop hearing.
This means that you continue to hear at night.
Thankfully though, your brain learns to ignore most of the sounds being received so that you can sleep.
As you quieten down for the night, you may notice that any tinnitus becomes louder as the noise of the day diminishes and you might then focus more on the tinnitus sounds.
And even in sleep, unusual or loud noises wake you up!
12. You can ‘hear’ food
Sounds strange but taste is not solely about the impact of the food on the taste buds in your mouth, but is also related to smell and, perhaps surprisingly, to hearing.
After all, you listen as you crunch into a crunchy apple, or to the sound of ice clinking in a cool drink.
The sounds you receive give you information about the food, a crunchy apple is likely to be fresher than a soft one, the fizz of a freshly opened bottle of cola versus a flat one.
Studies have even shown that listening to certain types of sounds can affect how food tastes.
Eating is ‘cross modal’, involving multiple sensory systems: if you ‘eat with your eyes first’, the other senses are also involved!
Finally – why do we have earlobes?
No one truly knows what purpose they serve aside from having somewhere to put earrings!
They have a good blood supply which may help keep ears warm as they are quite exposed to the elements!
All about earwax
YOU shouldn’t stick cotton buds down your ears to clean them but sometimes earwax does build up.
You might have a buildup of wax if you have:
- Hearing loss
- An earache or feeling that your ears are blocked
- A ringing or buzzing in your ears (tinnitus)
- Vertigo (feeling dizzy or sick)
Earwax tends to fall out on its own.
If it does not, and builds up and blocks your ear, you can try to remove it – but not with your fingers, a cotton bud or any other object, as this can damage your ear and push the wax further down.
You can buy some ear drops at the pharmacy or the NHS also suggests using olive or almond oil (but not if you’re allergic to almonds).
To remove earwax build-up:
- Lie on your side with the affected ear facing up.
- Put two to three drops of olive or almond oil in your ear.
- Continue to lie on your side for five to 10 minutes after putting in the oil.
- Repeat three to four times a day, for three to five days.
Over about two weeks, lumps of earwax should fall out of your ear and your symptoms should improve.
There’s no evidence that ear candles or ear vacuums get rid of earwax.
Do not use drops if you have a hole in your eardrum (a perforated eardrum).
You can also speak to a pharmacist about earwax buildup for advice and treatments.
You should see a nurse at your GP surgery if:
- You have symptoms of ear wax build-up which have not cleared after five days
- Your ear is badly blocked and you cannot hear anything – you could get an infection if it has not cleared
Some GP surgeries can remove your earwax by:
- Flushing out the was with water (ear irrigation)
- Sucking out the wax (microsuction)
Source: NHS