Headed to a concert this summer? Pack earplugs

If you’re headed to a rock concert this summer, you may want to pack earplugs. Stuffing the spongy blobs in your ears may seem strange, especially if you’re going to listen to live music. Doing so, though, just might prevent hearing loss, a new study finds.

Wearing earplugs at a 4.5-hour music festival reduced the risk of temporary hearing loss and ringing in the ears, a study found. Reducing how often such temporary changes occur can prevent permanent damage to the ears.

Most people have no idea how serious hearing loss is until they experience it, notes Wilko Grolman. He’s an ear, nose and throat doctor in the Netherlands at University Medical Center Utrecht.

Some 1.1 billion teenagers and young adults are at risk of hearing loss, the World Health Organization estimated last year. A main cause is their exposure to loud recreational sounds. This includes listening to music too loudly on mobile devices and attending live music events.

To understand how loud music can affect hearing, Grolman, his colleagues and several companies (including MTV Europe and Soundkeepr Earplugs among others), set up an experiment. Their field tests took place at a Dutch music festival in Amsterdam, last September 5. Through social media, the researchers recruited 51 people. The volunteers all got a free ticket to the event.

The team tested each participant’s hearing before the music festival started. Then it split the group in two. Half were given earplugs to wear during the 4.5-hour concert. The rest listened to the music normally.

And the music was loud. Measurements showed sounds routinely hovered at around 100 decibels. That’s a level within the range at which hearing loss may occur — especially if the noise level is persistent.

After the festival, the researchers tested each volunteer’s hearing again. Compared to those who wore earplugs, those listening with unprotected ears were roughly five times as likely to have some temporary hearing loss. They also had a higher rate of tinnitus (TIN-ih-tus) — ringing in the ears.

Grolman’s group published its findings April 7 in JAMA Otolaryngology — Head & Neck Surgery. Otolaryngology is the study of diseases of the ears and throat. (The American Medical Association publishes this journal.)

Hearing loss affects high pitches first

“It’s important to do studies on noise exposure, hearing and earplugs because hearing health is something that a lot of people don’t think about,” says Elizabeth Beach. She is a research psychologist at Macquarie University in Sydney, Australia. She says the new results match data from interviews she and colleagues had done for earlier studies.

The new study was designed to avoid any bias that might come from people choosing to wear earplugs or not, Grolman notes. Beach’s study, for instance, showed that some people wear earplugs to loud music events because of past hearing loss or because of the perceived protection they provided. In contrast, it was researchers that decided who would wear earplugs for the new study. And they made the decision solely based on random chance. That gave Grolman’s team high confidence that its results would hold true for the population at large.

The team tested the participants for hearing loss after the concert by measuring how well they could hear sounds at different frequencies. A sound’s frequency is what people think of as pitch — that is, how high or low it sounds. When hearing starts to go, people tend to lose an ability to detect high pitches first. Eventually, the loss can go down to the range of frequencies typical of speech.

People don’t usually notice temporary hearing loss. “For example, you may hear the birds singing before a loud event, but you may not hear them afterward,” Grolman explains. Scientists call this effect a temporary threshold shift. It can last for seconds, hours or longer. But repeated exposure to loud sounds can add up, causing permanent damage, he notes.

“Earplugs are an effective protective measure. They reduce the symptoms of hearing damage,” says Beach. There are, however, other ways to protect your ears. The easiest is to turn down the volume, to stay away from speakers and to take breaks from loud spaces.

Grolman agrees with these noise-prevention steps. Still, he wants to go a step further in his research. “Our ears are extremely important,” he says. “But it is almost impossible to convince people to protect them.” His team plans to investigate why people resist using earplugs and other protective gear or controlling sound levels in the car and on the phone.

“We want to understand the emotional sensation, the rush loud music gives us,” he says. “We need to understand that in order to get people to do what they need to do to prevent hearing loss.”

Power Words

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bias   The tendency to hold a particular perspective or preference that favors some thing, some group or some choice. Scientists often “blind” subjects to the details of a test (don’t tell them what it is) so that their biases will not affect the results.

decibel   A measurement scale used for the intensity of sounds that can be picked up by the human ear. It starts at zero decibels (dB), a sound hardly audible to people with good hearing. A sound 10 times louder would be 10 dB. Because the scale is logarithmic, a sound 100 times louder than 0 dB would be 20 dB; one that’s 1,000 times louder than 0 dB would be described as 30 dB.

frequency   The number of times a specified periodic phenomenon occurs within a specified time interval. (In physics) The number of wavelengths that occurs over a particular interval of time. (in music) The pitch of a sound. Higher wavelengths are higher pitched than lower wavelengths.

psychology     (adj. psychological) The study of the human mind, especially in relation to actions and behavior. To do this, some perform research using animals. Scientists and mental-health professionals who work in this field are known as psychologists.

otolaryngology    A medical specialty for physicians who specialize in diseases of the ears, nose and throat.

social media   Internet-based media, such as Facebook, Twitter and Tumblr, that allow people to connect with each other (often anonymously) and to share information.

temporary threshold shift    (in medicine) A short-term inability to hear sounds above a certain frequency, usually a fairly high pitch. Here the “shift” is in the lowest pitch that the ears can detect. Such a shift can occur after exposure to loud noises, such as a gunshot, jet engine or loud music.

tinnitus    An uncontrolled and non-stop ringing or buzzing in the ears, usually triggered by tissue damage from exposure to loud noise. It can be short-lived, lasting hours or a day. In some instances, however, people may experience it for years or decades.