Testing for hearing loss The human ear is the envy of even the most sophisticated acoustic engineer. Without a moment's thought or the slightest pause, you can hear the difference between a violin and a clarinet; you can tell whether a sound is coming from your left or your right, and if it's distant or near; and you can discriminate between words as similar ashearandfear,sound andpound. Nearly everyone experiences trouble hearing from time to time. Common causes include a buildup of earwax or fluid in the ear, ear infections, or the change in air pressure when taking off in an airplane. A mild degree of permanent hearing loss is an inevitable part of the aging process. Unfortunately, major hearing loss that makes communication difficult also becomes more common with increasing age, particularly after age 65. Get your copy of Coping with Hearing Loss: A guide to prevention and treatment   If you think you might need a hearing checkup, you probably do. This Special Health Report, Coping with Hearing Loss: A guide to prevention and treatment, contains in-depth information on the causes, diagnosis, and treatment of hearing loss. You'll learn how to prevent hearing loss and preserve the hearing you have now. You'll also learn about the latest advances in hearing aid technology and find out which kind of hearing device may be best for you. Testing — 1, 2, 3 How do you know if you need a hearing test? If you answer yes to any of the questions below, talk with your doctor about having your hearing tested: Are you always turning up the volume on your TV or radio? Do you shy away from social situations or meeting new people because you're worried about understanding them? Do you get confused or feel "out of it" at restaurants or dinner parties? Do you ask people to repeat themselves? Do you miss telephone calls — or have trouble hearing on the phone when you do pick up the receiver? Do the people in your world complain that you never listen to them (even when you're really trying)? You can also ask a friend to test you by whispering a series of words or numbers. After all this, if you think you have a hearing problem, you should have a test. What does a hearing test involve? Thorough hearing evaluations start with a medical history and examination of your ears, nose, and throat, followed by a few simple office hearing tests. An audiogram is the next step. For an audiogram, you sit in a soundproof booth wearing earphones that allow each ear to be tested separately. A series of tones at various frequencies are piped to your ear. An audiologist will ask you to indicate the softest tone you can hear in the low-, mid-, and high-frequency ranges. People with excellent hearing can generally hear tones as soft as 20 decibels (dB) or less. If you can't hear sounds softer than 45 to 60 dB, you have moderate hearing loss, and if you don't hear sound until it's ramped up to 76 to 90 dB, you have severe hearing loss. Hearing tones is nice, but hearing and understanding words is crucial too. For this reason, the audiologist will also play tape-recorded words at various volumes to find your speech reception threshold, or the lowest dB level at which you can hear and repeat half of the words. Finally, you'll be tested with a series of similar-sounding words to evaluate your speech discrimination. For more on diagnosing and treating hearing loss, read Hearing Loss: A guide to prevention and treatment, a Special Health Report from Harvard Medical School. Image: monkeybusinessimages/Getty Images Share this story:

One hearing aid or two? If you're like most people with hearing loss, you'll probably find that it takes time to accept the idea that you need a hearing aid, and you may be unhappy when your audiologist recommends that you get not one, but two. Chances are that your first question will be, "Is it normal to get two hearing aids?" And then, "Do I really need two?" If you have hearing loss in only one ear and normal or nearly normal hearing in the other, then one hearing aid is all you need. But most people have hearing loss in both ears, especially if the loss is age-related. (You may have one ear that's better than the other, but chances are both will be in the same ballpark.) In that case, research and experience suggest that you'll ultimately be more satis-fied with two hearing aids. 2 hearing aids, 3 advantages When you have two hearing aids, you can take better advan-tage of the way the brain processes sound through what's known as binaural hearing. With normal hearing, sound signals from both ears are comparable in strength. The brain can pick out the impor-tant signals, like voices, when they're louder than the background noise. But if you're wearing just one hearing aid and someone talks into your unaided ear in a noisy room, the voice may sound softer than the background noise. As a result, it's harder for your brain to give it preferential status. It may also be harder for the brain to identify the location of particular sounds if you're wear-ing a single hearing aid. The brain normally does this by comparing the qualities of the sound signals that come through each ear—their relative loudness, their frequencies, and the time it takes them to travel through the ears. But the brain can't locate a sound as well if sound signals are always louder through one ear. Wearing wireless hearing aids in both ears enhances the binaural hearing process because the hear-ing aids communicate with each other and transfer data back and forth, rather than working inde-pendently to process sound. This means they are able to maintain localization cues better than hear-ing aids working independently of each other. Some hearing experts think that wearing two hearing aids may even help conserve hearing in the weaker ear by keeping the auditory nerve stimulated with adequately amplified sound. There's no proof that the auditory nerves actu-ally deteriorate from inadequate stimulation, but research shows that other parts of the nervous sys-tem—most notably the brain—do suffer from lack of use. One undisputed advantage of wearing two hearing aids is that you can set them at a lower vol-ume than if you wear just one. That's because soft tones sound louder when the brain is receiv-ing signals from two ears rather than one. And lower volume means less feedback. If your audi-ologist recommends two hearing aids and you're not sure that you want or need two, ask if you can use two on a trial basis. Under this arrangement, you would be fitted with two hearing aids and then, over a period of several weeks, you would decide whether you hear better with two. If not, you should be able to return one of them. Keep in mind that if you want to take advantage of wireless features, both hearing aids must be wireless.  For more on diagnosing and treating hearing loss, read Hearing Loss: A guide to prevention and treatment, a Special Health Report from Harvard Medical School. Image: LightFieldStudios/Getty Images Share this story:

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Coping with Hearing Loss: A guide to prevention and treatment Featured content: • How we hear • When hearing loss occurs • Testing for hearing loss • SPECIAL SECTION: Selecting a hearing aid • Surgery for hearing loss • Living with hearing loss • Preventing hearing loss Click here to read more »