First Steps To Reading An Audiogram
If you’ve had a hearing test, you may have been given a chart called an audiogram. This is a visual representation of your hearing ability, but if you’ve never seen one before, you may not know what you’re looking at. Well, we’re here to help! Let’s go over the basics of how to read an audiogram:
First, let’s look at the horizontal axis of the graph. You may see numbers from 250 Hz to 8000 Hz listed; these are different pitches, from bass tones on the left to treble tones on the right. Then let’s look at the vertical axis, which has loudness expressed in decibels (dB), with very soft sounds at the top of the graph and very loud sounds at the bottom of the graph. Your results are shown on this graph using a blue X symbol for the left ear and a red O symbol for the right ear. Each mark is your hearing threshold at that particular frequency: in other words, how loud that tone had to be before you could detect it. Technically, your hearing threshold is the intensity at which you can detect the tone 50% of the time, so if you aren’t sure whether you actually heard the tone or not, that’s exactly what your hearing care professional was looking for – the softest sound that you could just barely detect!
Hearing, of course, is not all or nothing, and your audiogram shows exactly what types of sounds you have trouble hearing. The most common type of hearing loss is a high-frequency sensorineural hearing loss, meaning that your hearing is worse in the high frequencies – toward the right side of the chart – and better, possibly even normal, in the low frequencies. If your audiogram shows this configuration, you probably feel like you can hear but not understand, particularly in noisy environments, and that everyone sounds like they’re mumbling.
The vertical axis of the audiogram is also what allows your hearing professional to determine your degree of hearing loss. Zero decibels, at the very top of the graph, represents perfect hearing (not an actual absence of sound), and if your marks are from about zero to 15 decibels, your hearing is normal at that pitch. The degrees of hearing loss then proceed through borderline, mild, moderate, severe, and profound, and you may have marks in more than one zone; your hearing loss would then be described as something like “mild to moderate” or “moderate to profound,” which is a much more meaningful description than a percentage! One or two thresholds outside the normal range may not be enough for you to need a hearing aid, but if enough of your thresholds fall below normal or they fall far enough below normal, your hearing care professional will likely talk to you about hearing aids.
Got it so far? Great! There’s more! If your hearing test was a comprehensive evaluation including both air conduction (headphones) and bone conduction (a headband with the sound generator placed behind your ear), your audiogram will also tell you what type of hearing loss you have. Most hearing losses are sensorineural, meaning the problem is your inner ear; for these, the little bone conduction brackets will be within ten decibels of the O and X marks for air conduction. However, if your hearing loss is caused by something preventing the sound from getting to the inner ear in the first place (examples include a wax impaction, a large hole in the eardrum, or a disorder of the middle ear bones), you have a conductive hearing loss and the bone conduction marks will be significantly higher on the graph than the air conduction marks. Some conductive hearing losses are best treated by hearing aids, but others require medical evaluation and may even be surgically correctable.
You may be wondering why any of this matters. After all, the important sounds in your life are not pure tones like the ones used in hearing tests! Does it really matter if you hear low tones better than high tones when the real problem is understanding what people are saying to you? The answer is: it most certainly does! Every individual’s voice, whether they have a high voice or a low voice, contains sounds of every frequency. Vowel sounds are louder and lower and easier to hear, while consonant sounds tend to be softer and higher pitched – right where the most common type of hearing loss falls! If you hear vowels well but miss many consonants, you’ll experience this as a loss of clarity, and you will sometimes misunderstand things that people say to you. This is why high-quality, properly programmed hearing aids are so important. Cheap amplifiers tend to boost all sounds equally, whether you need them or not. A good set of hearing aids can be fine-tuned by your hearing professional, using your audiogram as your prescription, to boost only the sounds that you need to compensate for your individual hearing deficits.
Do you have an audiogram that indicates a hearing problem? We’d love to help. Give Earlux a call at (833) 4-EARLUX to talk through hearing aid options!