Contributed by Debbie Clason, staff writer, Healthy Hearing
Stop for a moment and notice what you hear. Really pay attention. Beyond the likely suspects of people talking or the volume of the television, what’s going on in the background? Can you hear traffic? Is the neighbor’s dog barking? Are any of your appliances humming along?
Truth be told, much of your hearing is on autopilot. Our brain is processing the sounds our auditory system collects as automatically as we inhale and exhale. In fact, the way we hear is a fascinating and, sometimes mysterious, process. So, in honor of hearing enthusiasts everywhere, here are five things you may not know about how your hearing works.
What happens when sounds enter your ears?
Have you ever thought about what happens once sound enters your ears? Just as the brain interprets the images your eyes see, the brain is also responsible for interpreting the sound your ears collect. Very simply, here’s how it works:
- Your outer ear (pinna) acts like a satellite dish to collect sound in our environment and funnel it to the inner ear.
- The inner ear translates the sound into electrical impulses and sends it along the auditory nerve.
- Once the electrical impulses reach the brain, it interprets them into recognizable sound.
What are stereocilia and what do all those tiny hairs do?
You cut and style the hair that grows on your head; sometimes the hair on your arms and the back of your neck stands up on end when you’re feeling uneasy — but did you know you have a completely different set of sensory hair cells in your inner ear that are responsible for how you hear?
Also known as stereocilia, the hair cells in the inner ear receive sound vibrations from the outer ear and change them into electrical impulses that they send to the brain along the auditory nerve. These hair cells — approximately 16,000 of them — are rolled up like a carpet inside your cochlea. The hair cells on one end of the carpet are responsible for translating vibrations for higher-pitched sounds and, much like a piano keyboard, those on the other end are responsible for sound vibrations in the lower register. When these hair cells die, you lose your ability to hear different sounds, depending on where the damaged stereocilia are located. Unlike the hair on your head, unfortunately, the hair cells in the inner ear do not grow back once they are damaged or die.
Many things can damage these delicate hair cells, but noise-induced hearing loss (NIHL) is one of the most common — and preventable. According to the National Institute of Health, approximately 26 million Americans between the ages of 20 and 69 have hearing loss and as many as 16 percent of teens age 12 to 20 have reported hearing loss that may have been caused by NIHL. Hearing healthcare professionals agree: If you can limit your exposure to noise louder than 85 decibels, you can minimize the permanent damage to the hair cells of the inner ear. (In other words, turn down the volume and use hearing protection if you have noisy hobbies, such as hunting or woodworking.)
Do left and right ears handle sound differently?
Yes, for many people, the left and right ears handle sound a little differently. If you have hearing loss, one ear probably has more than the other — but even more than that, since birth, your ears have been partial to different sounds.
Scientists have discovered that the left and right ears process sound differently. The right ear responds more to speech and logic while the left ear is more tuned in to music, emotion and intuition. Scientists believe it’s because speech is processed primarily in the left hemisphere of the brain, while music (and other creative functions) are processed in the right hemisphere.
This may explain why those with greater hearing loss in the left ear may have trouble understanding friends and family’s emotional issues while those who have greater hearing loss in the right ear seem to lose some of their ability to sort things out.
How do the two ears and brain work together?
Having an ear on each side of our head — known as binaural hearing — helps the brain determine where sound is coming from, increases the range you are able to hear, and provides a more balanced, natural quality of sound. You can hear dramatically better with two ears than you can with one. That’s the main reason why hearing healthcare professionals recommend wearing two hearing aids when you have hearing loss in both ears.
Does hearing loss really make you tired?
If you find you’re tiring more easily than you used to, it may not be your age — it might be hearing loss. Remember the automatic listening mentioned at the beginning of this article? When you have hearing loss, you have to concentrate more to understand what you’re hearing. You may even be guessing what people are saying by reading lips, facial expressions and body language.
In fact, a study by the Better Hearing Institute estimates that untreated hearing loss costs the United States $56 billion each year in lost productivity at work, much of which can be blamed on hearing loss fatigue. A survey by the Danish Institute for Social Research found that as many as one in five people with hearing loss stop working altogether. Of those who do work, 15 percent are too tired at the end of the day to pursue leisure activities.
Fortunately, hearing aids can reduce hearing loss fatigue. When the sounds in your environment are amplified, it takes less effort for you to hear speech and other sound. Today’s technology makes it even easier. Many hearing devices have features which isolate and amplify the sound you want to hear while significantly reducing or removing background noise.
Struggling with hearing loss?
Now that you’re more aware of how your hearing works, don’t forget to schedule a visit to a hearing healthcare professional for a thorough hearing evaluation if you suspect you have hearing loss. Establishing a baseline level for your hearing as well as a relationship with a reputable hearing healthcare professional is a great first step toward hearing health. Find a hearing instrument specialist or audiologist near you.