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I remember that some years ago one of his dogs thought his aids were dog biscuits and decided to chew them up - which cost him $2000 to replace! Other aids that he has tried have driven him to distraction trying to remove the batteries with arthritic fingers: and for others he has had to create fine instruments in an attempt to remove the wax that gets plugged in the narrow hearing tube of the aid.
There are three groups of hearing aids, apart from Cochlear implants which have been very successful for the more profoundly deaf, and the different types are described as:
Behind the ear
In the ear
In the canal
.. depending on where the bulk of the mechanism is.
All are designed to augment the ambient noise and transmit it to the ear drum with the intention of improving the persons hearing. But there are a number of problems with this approach as despite the fact that the aids are effective microphones and do make the sound louder, they don't discriminate the incoming sounds; so in a noisy room, the aids make all the noises louder much to the confusion of the hearer. Also, the hearing deficit is not usually caused by a defective ear drum but with with the hearing receptor cells - the hair cells - deep within the ear, which have "worn out". Whilst here has been some exciting work done with using stem cells to grow new hair cells, that promise is well into the future.
With all these problems it is not surprising that of those who need to use hearing aids only 14% of those in the US and 17% of those in France actually use them.
Many of those with hearing deficits have already become fairly good at lip reading, and at least it has the benefit of being free and universally available. There is a massive need to provide cost friendly hearing aids for an aging population, so if any of you have any suggestions on how you have overcome your hearing problems, or things that have worked for you over the years, then please let me know so that I can pass it on to others.