Images from: Venema, T. Compression for Clinicians 2nd Edition, Thomson Delmar Learning 2006
If you feel like the amplification you receive from hearing aids can damage your hearing, you're not alone. After all, for some hearing losses, hearing aids need to crank out a lot of sound just to make that sound audible to the wearer.Too much exposure to loud sound could damage the hairlike structures inside of the cochlea, otherwise known as your hearing organ.
Individuals with normal hearing have 3 rows of Outer Hair Cells (OHCs) and 1 row of Inner Hair Cells (IHCs). If you lose all of your Outer Hair Cells, you will be left with a Moderately Severe hearing loss.Although, even though hearing aids do make sounds louder, it doesn't mean that they will damage your remaining hearing. In a recent research study by Earl Johnson that was published in the International Journal of Audiology, he looked at the potential of increased hearing loss due to the use of hearing aids. He concluded that it was very unlikely that additional hearing loss could occur from hearing aid amplification.
The one area that he did find additional risk was for individuals with severe to profound hearing loss already. This assumed an 8 hour average daily exposure to noise at levels that would indicate working in a factory or construction site.All this being said, the perception that hearing aid wearers have is that their hearing is worse when they take their hearing aids out.
This is due to an Adaptation and Comparison effect. When you wear hearing aids, your brain adapts to the new level of sound. When you take the hearing aids out, you experience an immediate reduction in your hearing ability. Even if your hearing hasn't changed at all.All that being said, even though damaging your hearing with hearing aids is unlikely, it is possible to cause additional damage to your hearing if your hearing aids aren’t programmed correctly.
Ensuring that amplification levels do not exceed a dangerous level is controlled in the hearing aid programming software.During programming, your hearing care professional will limit the Maximum Potential Output (aka. MPO) of your hearing aids. Which is the Maximum amount of Sound that your hearing aids will generate. However, you can’t just drop the MPO to a low level to prevent any risk of increased hearing damage. Too low of an MPO and your speech understanding and music appreciation will suffer. The trick is to set the MPO at the correct level to maximize benefit and limit the risk of additional hearing loss.
This is one of the risks to purchasing hearing aids online. If you don't have devices that are programmed correctly, you could end up with worse hearing than you did before purchasing those devices. So if you are one of those individuals who are worried about your hearing aids making your hearing loss worse, just know that as long as you have the right hearing aids programmed the right way, it isn’t something you need to worry about