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How To Understand Your Audiogram

Understanding an Audiogram or hearing test.

A hearing test is usually performed by an audiologist or a hearing aid dispenser, although your family doctor may have a testing machine in the office. From the hearing test comes a number of printed sheets of paper. The most important sheet of paper is a graph that displays your ability to hear sounds across the range of frequencies that were tested - the audiogram. The audiogram is a physical representation of your hearing capabilities that shows the range of pitches or frequencies that you’re able to hear with each ear, and at what intensity level you’re able to hear them. Frequency is measured in hertz, which we perceive as pitch. Intensity is measured in decibels, and is perceived as loudness.

Pitch and Loudness Range Test.

To take this test, you’ll wear headphones and possibly sit in a sound booth so that any ambient noise is minimized. Your tester will likely use an audiometer, a machine that produces pure tones of different frequencies and intensities. Then you’ll be asked to listen, first with one ear, and then the other, to a series of pure tones, signaling when you hear each tone. The tones begin to decrease in intensity levels until you can no longer hear them—a point known as your “hearing threshold.” The audiogram plots your hearing threshold at various frequencies from 250 to 8000, the range that is characteristic of the range of human hearing.

Spoken Word Test.

You may also be given a test for how well you hear the spoken word. This test measures the ability to hear and distinguish actual words. You’ll be asked to listen to and repeat a series of words, first at decreasing intensity and then at varied sound levels. The results determine your speech threshold, or the softest levels at which you can hear speech, as well as how well you can discriminate between words at different frequencies. The normal range of speech sounds results is shown in the graph below in the curved area.

The graph above has all you need to understand the extent of your hearing loss. You will be given a similar one, probably just printed or copied in black and white.

Results Layout:

The pitch scale runs along the horizontal (top) of the right graph. This scale measures the range of sounds you were given to hear, from the low bass sounds to the high squeals. Running along the left scale of the graph from top to bottom is the loudness (in decibels) of the pitches that you were given to hear.

Left and Right Ear Hearing Test Results

Look at the blue and the red lines that cut through the graph. These lines show your test results against the pitch and loudness sounds you were given. The right ear is always given the "O" symbol and the left ear is always given the "X" symbol. Each time you see the X's and O's marked on your hearing test, it means that the tester tested you at a specific pitch and loudness and those were the results, called a test point. Each of the test points are connected to form the lines. The lines can be of any color, but happen to be blue and red in this graph.

Analyzing Your Hearing Test Results

Most people naturally lose the ability to hear some high pitches with age. As long as older people who do not have anything else wrong with their middle or inner ear, will show something like the graph above, or something like a bell curve, with a lower right drop.

Now, look at the following graph. The solid line for the right and left ear at the top of the chart shows someone with no hearing loss. The dotted lines on the bottom two lines show someone who listed too long to loud music when they were younger or worked around sounds that were greater than 120 Db (decibels). If you listened to heavy metal or rock bands when you were younger, you may get a result like the dotted lines. The sharp up-tick on the dotted line between 4000Hz and 8000Hz show continued exposure to loud sounds over time.

How Bad is Your Hearing?

In many cases, your audiogram will show the right side of the plots as dropping to the right. The bottom-most value on the dB level is the most important for deciding if and what kind of hearing aid to purchase. If any part of your graph shows test point results between 30dB and 50dB, then you have moderate hearing loss in that ear and you would choose a hearing aid that addresses moderate hearing loss. If any part of your graph shows test point results between 50dB and 80dB then you have a severe hearing loss in that ear and you should choose a hearing aid that addresses moderate to severe hearing loss. Greater than 80dB and you have a profound hearing loss, and there are very few hearing aid models that will help you. To decide if and what type of hearing aid you might need, see the article "What Hearing Aid is Best For You?".