Hearing loss, is it a volume problem?

Anyone who is not familiar with hearing loss assumes that it is like turning the volume on a radio lower and lower until,you have difficulty understanding the words, or cannot hear at all.
Hearing loss is far more subtle than that.
A person with hearing loss usually has a different amount of loss at each frequency across a range of hearing. For example, a person may have normal hearing in the lower frequencies,  a moderate hearing loss in the middle frequencies and a severe loss in the high frequencies.
In relation to hearing aids,and in order to understand speech better, the person wants the low frequencies unchanged,the middle frequencies a little louder, and the high frequencies very loud.
Increasing the volume of the radio makes all the frequencies louder. The volume is so loud in the lower frequencies,where the hearing is normal, that it becomes intolerable. Louder does not mean clearer in relation to frequencies unless the frequencies are properly balanced.

Why do most people dislike loud noise?

Most people do not like loud noise. Some people have particularly sensitive ears, they cannot bear ordinary levels of noise.
Hyper sensitive hearing is most commonly associated with hearing loss.Have you noticed how some older people ask you to speak up a bit. After a while they may ask you to stop shouting or they may say "I'm not deaf".


Loudness discomfort is typically a problem for people that suffer from a sensorinueral hearing loss (A sensorineural hearing loss is caused by damage or a disorder of the inner ear, or of the auditory nerve, nerve fibres going from the inner ear to the brain stem).


However this is not a problem who suffer from a conductive hearing loss(A conductive hearing loss involves the breakdown or obstruction of some part of the external or middle ear which transmits or conducts the physical vibrations of sound through air, bone or tissue.)


As we age, the number of hair cells and nerve fibres that are responsible for picking up in the inner ear is reduced.The ability to grade different intensities of sound is reduced. How do we compensate for this? 
Our brain will "switch on " all remaining nerve fibres to produce almost maximum loudness. As a result, even quite moderate sounds may seem to be unbearably loud.


The dynamic range is narrowed or reduced in the ears: If sounds are heard at all, they are heard as loud noises.


When a person suffers from hearing loss and needs to use hearing instruments, the hearing instruments should not overload the ear with amplified sound. To overcome this, many hearing instruments have "peak clipping". Another more sophisticated form of compression is known as automatic volume control.


Some recent research has shown that in some cases the use of white noise applied to the ear by a white noise generator masker can help.

Hearing aids stimulate brain activity

On average it takes 10 years for a person with a hearing loss to finally do something about it. The first reaction to a hearing loss is to wait for it to go away. This rarely happens.

Untreated hearing loss affects your quality of life, but it also affects the brain's ability to remember common everyday sounds because the hearing channels are no longer effectively used.

When the hearing nerves lose their function and no longer channel sound signals to the brain, the brain "forgets" the sounds over time and becomes unable to understand them.

Memory weakening

The brain centre for hearing stores sounds and noises for up to three years following the onset of hearing loss. But after about seven years the memory becomes weaker and weaker.

Therefore, it is important to have your hearing tested and hearing aids fitted when you find that you are losing some of your hearing. After fitting of hearing aids the hearing process resumes suppling signals to the brain.

Learning to hear again

If you delay the fitting of a hearing aid for any great length of time there could be serious consequences. Even the most tecnically advanced hearing aid may not be able to transform the incoming signal into understandable information. The brain no longer recognizes ordinary everyday sounds and noises, such as the hum of a refrigator or the noise of a computer. The brain must learn to hear all over again.

Improved quality of life

A study published by the Quality of LIfe Research journal indicated that hearing impaired people estimate their hearing to have improved while wearing a  hearing aid does more than help you to hear. A hearing aid improves your quality of life and improves your brain's function.

Most often hearing loss sneaks up on you. Suddenly one day you notice that you no longer hear the humming of the refrigerator or or the bird's singing.

Five improved 100% when treated with hearing aids. This is in contrast to their belief before being fitted with hearing aids that their hearing was inadequate.

The researchers conducting the study asked 98 people with hearing loss how they perceived their quality of life after the fitting of hearing aids. The results of the study confirm that people with hearing loss report improvements in their quality of life when they receive and adapt to hearing aids.

To find out more information on the human ear click here

What happens when the cochlea is damaged?

Cochlea Damage The majority of hearing losses in the world are due to damage caused to the cochlea,(sensori-neural). In nearly all cases the patient will struggle with speech discrimination ( "I can hear your voice but you sound like you are muttering")


This is made even worse in the presence of background noise. The fitting of hearing aids will be beneficial, but simply amplifying sounds will not overcome the problems found in the cochlea. We will now look at the various problems within the cochlea.


Loudness Recruitment


People with cochlea damage need a greater level of sound to hear well, but when sounds get louder they become just as intolerant of loud sounds as people with no hearing impairment. As seen in audiometry, this leaves the patient with a reduced dynamic range. This causes problems with speech discrimination, as the dynamic range of speech is about 50dB i.e. a 50dB intensity difference between the loudest and quietest parts of speech.Someone with a reduced dynamic range may not be able to accommodate the whole range of speech, which could become a problem when a hearing aid is fitted.


A hearing instrument with the ability to adjust the amounts of amplification will provide a better option for patients with a reduced dynamic range.Recruitment is found only in patients with cochlea (hair cell) damage. The term "abnormal growth of loudness" is commonly used and relates to patients perception of loudness throughout their dynamic range.

A full explanation of cochlea damage can be found here.

How Does It Feel Not To Hear Properly?

What Hearing Loss Really Means

1. Hearing Facts. Explain that when people cannot hear facts well and often have to ask people to repeat themselves, it is not only frustrating to the person with the hearing loss, but to the other person as well. The other person often wonders if there might be a mental problem, before considering that it might be a hearing problem. This consideration alone can represent a strong motivation to purchase hearing aids.

2. Understanding Meaning and Intention. Understanding the meaning behind a person’s words and understanding their intentions are critically important in many conversations. The person with a hearing loss must understand how this capability deteriorates as hearing gets worse.

3. Feelings and Emotions. Hearing loss makes it much more difficult for the patient to understand the feelings and emotions behind spoken words. This is particularly important to family and friends. The more familiar the relationship, the more important subtle intonation and inflection are. When meaning and emotions are not accurately understood due to hearing loss, misunderstandings lead to frustration and disappointment. This is one of the main reasons why families are often the driving force in visits to the hearing aid office.

4. Alerts and Warnings. Personal and family safety can be jeopardized in an instant by poor hearing. The inability to recognize the nature, seriousness, and direction from which a warning or threat comes is very serious. There is a point at which disregarding this concern becomes irresponsible.This can be overcome with modern technology.

5. Sounds of Nature. Hearing the sound of the wind in the trees, birds chirping, and rain on the roof are important parts of feeling part of a living world. As hearing deteriorates, an inevitable feeling of isolation closes in. Though this is experienced most prevalently in advanced hearing loss, it is one of the most unfortunate consequences of the situation getting worse.

6. Music. For many people with hearing loss, music sounds off key or distorted compared to when it was originally heard. Music plays an important part in some of our favorite memories. Hearing loss often makes sharing these memories stilted and uncomfortable.

http://www.all-about-the-human-ear.com/HearingLossReallyMeans.html

Gunshot blasts pose a serious hazard to hearing

The impulse noise from firearms is as intense as 132-165 Db and thus extremely dangerous to
hearing.
A Polish study including 18 hunters and 8 police trainees, with average ages of 46.2 years and
25.2 years, respectively, found that as many as 72.2 percent of hunters suffered from hearing
loss. Only 11.1% had completely normal hearing, and the remaining 16.7% had normal hearing
only in the ear furthest away from the rifle.
The hunters had never used hearing protection while hunting. The police trainees had always
used hearing protection when practising target shooting and none of them suffered from
measurable hearing loss.
In a comparison of the two groups their hearing was examined before and after a number of
test gunshots. Changes were noted in the hearing of the hunters, whereas no measurable
changes were found in the police trainees after the test shots. The latter group wore hearing
protection throughout the test shooting.
The study indicated that long-term exposure to gunshot blasts is not the only hazard when
using firearms. Even short-term exposure can cause temporary hearing damage and make the
ear more susceptible to noise damage later on.
On the plus side, the study confirmed that hearing protection prevents hearing loss. The use of
hearing protection is therefore highly recommended when using firearms.
Source; International Journal of Occupational Medicine and Environmental Health
http://www.all-about-the-human-ear.com/hearingprotection.html