A hearing
aid is a piece of electronic device which assists in restoring sound to persons
with impaired hearing by the amplification of the sound. It does this by
picking up the sound waves arriving at the external ear, processing them and
sending the amplified sounds back into the ear.
Hearing aids
now employ various types of hearing solutions to achieve this objective but
they are all made up of essentially similar component parts. An amplifier picks
up the sound waves as they arrive at the external ear and converts them into
digital signals which are processed by a microchip, a mini-computer, installed
within the hearing aid. The microchip is programmed by an auditory professional
to meet the specific needs of the user, based on the results of a hearing test
and the lifestyle of the user.
The signals
are then strengthened by an amplifier to boost them before being converted into
vibrations by a receiver which transmits them to the brain via the inner ear.
The microchip is a sophisticated computer-like silicon chip which continuously
modulates incoming sounds to ensure that only clear and audible sounds of the
appropriate level of amplification can be transmitted into the ear. This whole
device is powered by a tiny battery installed within it.
Analogue
hearing aids previously in use do not have these capabilities even though they
amplify sounds, but some are equipped with ‘automatic gain control’ features which
enable them distinguish between quiet and loud sounds so that loud sounds are
not further amplified to levels uncomfortable for the user.
Some hearing
aids are combined with a sound generator. These combination devices are
produced to assist persons suffering from tinnitus. The sound generator
provides extra low level sounds which help in getting used to the tinnitus
sound.
The modern
digital hearing aid automatically adjusts itself to the sound level in the
environment so that the user seamlessly adjusts to the varying sound waves
arriving at the external ear. This way, the user is able to take part in
conversations even when some participants are barely audible while others are
speaking at the top of their voices.
Digital
technology now makes it possible for modern hearing aids to be worn discretely.
Some are so tiny they are barely visible because they sit far enough within the
ear canal no one will notice them. The most advanced ones offer a wide range of
personalisation options and they can deliver higher quality sounds with more
natural listening experience. They can be enhanced to connect wirelessly to
devices such as mobile phone, tablet, TV or stereo system.
