Initially hearing aids were simple analogue amplifiers. A microphone collected the sound from all around the wearer, and an amplifier increased the volume before delivering it to the ear via a speaker. Although the vast majority of hearing aid wearers need two hearing aids, usually only one was provided. The earliest devices were boxes worn in the users breast pocket or clipped to a belt, later they became rather smaller but still bulky behind the ear fittings.
Developments in technology allowed hearing aid manufacturers to split sound into high and low frequency, meaning that the annoying low frequency sound could be amplified less, in favour of the higher frequencies required for clarity of speech. Gradually the number of divisions between frequency ranges increased until the advent of digital hearing aids which revolutionised sound management for the hard of hearing, by splitting sound into multiple chunks and adding specialist programs to handle differing environments.
The original analogue hearing aids are only a distant cousin to today’s hearing aids. But even hearing aids fitted in the private sector within the last two or three years have been superseded with ever faster computer chips allowing still more manipulation of incoming sound before it is fed through to the end user. Miniaturisation has also allowed many quite severe losses to be fitted with incredibly discreet instruments.
The most advanced instruments can make well over 500 million calculations per second, and using wireless connectivity a correctly fitted pair can even ‘discuss’ their surroundings and act to improve speech before we have even noticed.
The instruments Healthy Hearing provide use multiple microphones and advanced processors that analyse incoming sound right across the frequency range, before being adjusted by the processor. Speech is prioritised with the instruments homing in on the voices nearby, sometimes by turning selected microphones down to reduce sounds the system perceives as unwanted.
Of course everyone wants to get rid of background noise and hearing aids do that better today that they have ever before, however it is worth remembering that someone with normal unimpaired hearing will hear all the sounds that a new hearing aid wearer might attribute to ‘background noise’. The more complex the situations you find yourself in, the more you will get from an advanced system. Yet even if you go into a slightly varied sound-scape your hearing will be improved more, the better the technology you use. It has to be stressed however that not everyone needs the highest levels of technology. Your Audiologist will explore what is right for you.
With normal hearing you cannot just eliminate those sounds you dislike. Instead our brain learns to discriminate between sounds, choosing, or learning, to ignore what it doesn’t need. As an example, we have all heard of the scenario of someone moving into a house with a railway line at the bottom of the garden. To begin with it is obtrusive, but after a while, it gets to the stage where the home owner doesn’t even hear the sound. The sound is there and they do hear it, but the brain filters it out. The same can be said for a ticking clock you live with day to day, after a while it ‘stops ticking’… you have got used to it and so ignore it.
Getting used to hearing again in background noise follows the same principals because the same happens with clients who use hearing aids for the first time and it can even happen to clients who have upgraded to a new system that brings in more information. New sounds can seem to take over and interfere for a while, but with careful adjustments and a proper rehabilitation plan users can begin to move through a process of just hearing and start to listen then understand.
It can take weeks or even months for this ability to be completely mastered by the brain, depending on the severity of the hearing loss and the length of time it has been present. It also depends on the commitment of the hearing aid user. If you only wear them for just a few hours a day then it may take much longer to rehabilitate to sound. You can purchase a top quality guitar but not be able to play unless you practice, and similarly you can give a basic instrument to a top quality professional and they can get the very best from it. The same applies to how a top quality Audiologist might adjust your hearing aids, compared against someone who is less experienced or who allows less time.
Your Healthy Hearing Professional will include information and counselling on the ongoing process of learning to hear as part of the service we provide and sometimes having the adjustments at home makes all the difference between success and failure.
So, yes. Hearing aids do get rid of background noise, however you have to have the correct system, correctly fitted and you will need to allow time for your brain to catch up and re learn to categorise the sounds you are hearing.