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Hearing aids are a complex subject that is changing daily because
of advances in hearing aid technology. Like a lot of things that are technology-driven,
there are a lot of claims and counter-claims being made that this hearing
aid or that hearing aid is the newest, best, etc. The purpose of this
section is to give you a brief overview of what hearing aids can and can’t
do and a description of the various types.
How Hearing Aids Work
Hearing aids are nothing but tiny amplifiers that have been made small
enough to fit in or behind your ear. The original hearing aids didn’t
work so well because they boosted all audio frequencies the same amount.
Since most people’s hearing loss is worse at higher frequencies,
to get the sound loud enough at high frequencies the hearing aid had to
boost the sound at all frequencies. This caused the sound to be too loud
at lower frequencies and produced problems with feedback, distortion,
etc. The new digital programmable aids have improved this scenario somewhat
in that they can be programmed so that the amount they amplify the various
frequencies corresponds more closely to the patient’s pattern of
hearing loss. Also, most of them can be reprogrammed if the pattern changes.
Problems remain, however, in the inability of the hearing aids to distinguish
“background noise” from sounds you want to hear (like someone
speaking). The difficulty with this is that our amazing ability to focus
on a particular sound in the midst of competing sounds is probably a highly
complex skill that involves several levels of auditory processing as nerve
impulses travel from our ear to our brain. That a small electronic device
can’t replicate this to our satisfaction is not surprising, but
engineers at a number of hearing aid companies are continuing to work
on this problem and a solution may be forthcoming.
Is Smaller
Better?
It troubles me when I see ads touting the latest hearing aid as “So
small it fits entirely in your ear canal!!!” (There are usually
lots of exclamation points in these ads.) While there is nothing wrong
with being small, the truth is that for many people an in-the-ear (ITE)
aid is not the best choice. For example, an ITE aid is not powerful enough
for persons with severe hearing loss, and because the pickup microphone
and the amplifier are so close to each other, feedback can be a problem
if the aid doesn’t fit just right in the ear canal. Also, some older
persons have trouble getting the aid in and out of the ear canal or adjusting
it. Finally, often an ITE aid is more expensive.
The other type of hearing aid is a behind-the-ear (BTE) aid, and while
it is certainly somewhat more noticeable, it has a more powerful battery
than an ITE and can compensate for more severe hearing losses. Also, since
the pickup microphone is located on the part that’s behind the ear,
this places it farther away from the sound output so you have less problem
with feedback and distortion. The best advice I can give you is to go
to someone who takes the time to explain all options and then use your
best judgement. Also, since the degree to which a patient is happy with
their hearing aid varies tremendously even among persons with the same
degree of hearing loss, make sure that you have a 30-day trial period
in which to use your hearing aid.
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