our-hearing-sleeping

Our hearing

Our hearing is the only of our senses that is constantly active – also when we sleep.

Our hearing is important

Every day situation and quality of life can be affected by hearing loss. 

Our hearing constantly supplies us with vital information, as well makes us experience emotions and recall memories. Our hearing is important:

At work:

•Participating in group meetings 

•Talking on the phone 

•Following conversation in a busy office

At social occasions:

•Chatting to friends

•Participating in dinner conversations at a restaurant

•Interacting with grandchildren

•Talking on the phone

•Watching TV together with others

For our own safety:

•When walking near busy roads

•To be able to hear sounds that alert to danger like sirens and other traffic signals

•So we can be alert to a cry for help

When we learn:

•Allowing us to concentrate with little effort

•So we are able to communicate with instructors

•So we register information correctly

And you probably wouldn’t miss out on music, the laughter of children, or the caring words whispered by a loved person either. Or what about nature’s comforting sounds: the evening song of a black bird, the wind in the autumn leaves, the waves on the beach or the cracking sounds of a cosy bonfire.

How our hearing works

We have two ears and a brain to hear with. And for good reason.

Natural hearing
A healthy hearing system can recognise both low sounds (a double-bass or traffic) and high (a violin or the twittering of birds). In technical terms, that means frequencies between around 20 and 20,000 Hertz. What’s more, it can process very quiet sounds (the buzzing of a mosquito) and extremely loud sounds (a jet engine starting). This equates to volumes between 0 and more than 120 decibels.

Understanding speech
Our brain is particularly adept at understanding language, which it can cope with in all its various facets and in every situation. Whether we are sitting in a cafe, on the phone or in a lecture: our brain filters out a flood of irrelevant sounds to concentrate on those that we need to hear. It is thanks to this facility that we are able to focus on a single instrument in a symphony orchestra, or participate in intimate conversations in a noisy environment.

Spatial hearing
Our brain hears sounds 360 degrees around the head – at every angle around our head. Our brain can differentiate between front and back, up and down. This enables us to determine where a sound is coming from, how big a room is or whether there is an obstruction in the area.

How we hear

The anatomy of hearing

"Hello"

Auditory
canal
Eardrum
Hammer
Anvil
Stirrup
Eardrum
Nerve fibres
Cochlea
Back

The brain

Once impulses are sent to the breain, it processes the data so that we can select waht is relevant to the situation and follow it.

The inner ear

Processing begins in the inner ear and sound waves are transformed into electrical impulses. The snail-shaped cochlea is filled with fluid, sound waves cause this fluid to move and the movement is picked up by the sensory cells which send the electrical impulses to your brain.

The middle ear

Three tiny bones and the eardrum make up the middle ear. The hammer, the anvil and the stirrup. The stirrup is actually the smallest bone in your body. They work together to amplify sound waves.

The outer ear

Ever wondered why an ear is shaped as it is? The shape of your ear ensures that sound waves are captured and directed through the auditory cancl into your eardrum.

The brain works hard

Many people find it challenging to follow conversations in some places, like in a noisy restaurant. This is because speech is made up of a great number of different sounds, put together in a very rapid flow. Our brain constantly prioritises and organises all these sounds for us.

When it comes to hearing, it may come as a surprise to learn that the brain works harder than the ears. This is why in noisy environments, such as in a crowded restaurant, it can be very frustrating just trying to follow conversation. Even people with no hearing loss can find this challenging. Ordinarily your brain will be able to sort through all information you apply your attention to through a cognitive process: Simply the brain organizes the sound environment, selects the desired source and follows it. For people with hearing loss, however, the brain has to work much harder to make sense of sound because the input it receives from the ears is softer, less detailed, and/or unclear

Some sounds are heard better than others
The high-pitched consonant sounds like f, s and t are easily drowned out by louder, low pitched vowel sounds like a, o and u.This results in a person with hearing loss complaining that they can hear others are talking, but not what they are saying.

sensory cells fibres inner ear

What is hearing loss

If the ear is exposed to loud sounds over time, the tiny sensory cells and fibres of the inner can become damaged. This can lead to permanent hearing loss

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