Directional Hearing Aids: Understanding Speech in Noise
By Elizabeth Brassine, Au.D., Hearing Services of McKinney, Collin LIVING WELL Magazine
Did you know that your ears are directional? The shape of our ear blocks some of the sound coming from behind, while collecting sound coming from the side and front. Having two ears also is important to helping us localize sound and “hear directionally” (one of the reasons that two hearing aids are recommended over one).
Some animals, such as horses and dogs, can actually move their ears, which gives them highly directional hearing and the ability to tell very accurately where sound is coming from.
Hearing aids can also be directional. Hearing instruments with directional microphones have been available for more than 25 years, but there have been significant improvements in recent years.
Directional hearing aids can provide more amplification for sounds coming from the front and less amplification for sounds from the back. This can make it easier to understand speech when there’s background noise. Since you usually face the speaker, the speech (from the front) is amplified more and the noise (from behind) is amplified less. It’s recommended when someone is using directional hearing aids that they face what they want to hear and put their back to noise when in places like a restaurant.
In the past, the hearing aid user chose whether the instrument was in “directional” or “non-directional” mode. This was done manually with either a switch on the hearing aid or through a remote control. Today, hearing aids use digital technology to control directionality automatically and more precisely. The hearing aid might amplify sounds from all around the wearer, but automatically go into directional mode if someone is talking. To accomplish this, the hearing aid must be able to distinguish between speech and noise. However, some patient personalities may prefer to still use a manual control instead of automatic. Some patients will actually use both types of control (automatic and manual) depending on their listening demands and situations.
Incorporating directional microphones into your hearing instruments can allow you to take the first step toward better hearing in noise. Directional options come in many styles of hearing aids, including some very cosmetically appealing micro behind-the-ear devices.
Author Elizabeth Brassine is a Doctor of Audiology and the owner of Hearing Services of McKinney. She may be reached at 972-838-1300 or visit her website at www.hearinmckinney.com.
