Noise-Induced Hearing Loss
Do you have a favorite band you have always wanted to see live in concert? Mine is The Killers, and in 2017, I waited all day in line with my sister so we could have the perfect spot to see them. Although we reached the front row, we found ourselves directly in front of the speakers.
After leaving the concert, I could barely hear my sister talking to me, and it felt like my ears were stuffed with cotton. We tried showing videos from our phones to our mom, and I could barely recognize the songs I had heard just a few hours before.
My hearing returned to normal after 24 hours, but can one rock concert affect my hearing? Yes, loud sounds can affect our hearing. Exposure to loud sounds repeatedly can eventually cause permanent hearing loss.
Noise-induced hearing loss affects approximately 5.2 million children and 26 million adults. Some hearing loss may be noticeable immediately after loud sounds (like after your favorite band’s concert). However, it is common for hearing loss to be noticed many years after repeated exposure to loud noises. Signs of noise-induced hearing loss can include difficulty understanding conversations, difficulty hearing, constant high-pitched sounds like buzzing, ringing or chirping in the ear or difficulty hearing music or speech over the phone. In some cases, you may have increased sensitivity to sound and may become angry in the presence of loud sounds.
How do we hear the sounds in our environment, and why do some sounds cause more damage than others? Sounds in our environment travel through our outer ear and vibrate our eardrum. The vibrations move the bones in our middle ear and cause fluid to move inside our inner ear, or cochlea. The fluid movement in the snail-shaped cochlea causes tiny hair cells inside the cochlea to bend. This generates an electrical signal to our brains that help us to recognize and understand sounds. Once the sound goes away, the hair cells in our cochlea straighten so they can bend again with the next sound.
When we listen to loud sounds, the vibrations transmitted to our hair cells cause them to bend more than usual. Some hair cells are not able to straighten again and become permanently damaged. Hearing loss may not be noticeable when only a few hair cells are damaged, but listening to loud sounds too often can cause permanent noise-induced hearing loss.
How loud must a sound be to be deemed “too loud”? Sometimes it is evident when we are exposed to loud sounds in our environment, but often, it is not as obvious. Even everyday tasks like listening to music through our headphones or using household appliances can contribute to hearing loss over time. Sounds are measured by loudness or intensity, and a sound’s intensity is measured in decibels.
Chronic exposure to sounds greater than 85 dB can cause damage if you listen to them for more than eight hours. Some familiar sounds that surpass that threshold are hair dryers (94 dB), lawnmowers (90 dB), headphones at max volume (112 dB), rock concerts (120 dB), sirens (120 dB) or firearms (140 dB). The louder the sounds become above 85 dB, the less time you can listen to them safely. Although you likely aren’t using your hair dryer for eight hours at a time, you can still cause permanent hearing loss if you listen to multiple loud sounds throughout the day.
Noise-induced hearing loss cannot be reversed, but it can be prevented. An excellent first step is to identify the sounds you experience throughout your day that may cause damage. You can download apps on your smartphone to detect the decibel levels around you to track your sound exposure, and some smartwatches have noise exposure tracking, so you are alerted when sound levels around you are unsafe. If you are in a place with loud noises, you may need hearing protection like ear plugs. If you can’t reduce the noise in your environment, you may need to take listening breaks throughout the day by moving to a quieter area. In addition, you can lower the volume on your headphones or use noise-canceling headphones to prevent turning the volume too high.
If you take steps to reduce your noise exposure and you still notice hearing loss, it is important to talk to a health-care provider, such as an ENT or an audiologist. They will examine your ears and walk you through tests to identify your type of hearing loss. They may recommend strategies to compensate for your hearing loss, such as finding quiet listening environments when possible, being closer to those speaking, and using closed captioning on your television. They can help you choose devices to help you hear, like hearing aids, which help to make sounds louder and easier to understand.
In addition, the health-care provider may recommend assistive listening devices like telephone amplifiers or flashing alarm clocks to ensure you don’t miss out on important sounds throughout your day. If the hearing loss is severe or profound, they may recommend a cochlear implant, which is surgically placed in the cochlea and helps restore hearing.
Our ability to hear helps us navigate our world and communicate with our family and friends. Keeping our hearing health is important to maintain relationships, improve communication and enjoy that rock concert you’ve always dreamed of attending. Life is worth listening to, so take steps to protect your hearing one loud noise at a time!
Kaitlyn Tholen is a second-year medical student at LSU Health Shreveport School of Medicine. Gauri Mankekar, MD, Ph.D., is an assistant professor of otolaryngology-head & neck surgery at LSU Health Shreveport.