In an interview with Howard Stern, Foo Fighters frontman Dave Grohl revealed that he has noise-induced hearing loss (NIHL) and “had to read lips for the last 20 years” . Prior to playing guitar for the Foo Fighters, Grohl played drums for Seattle grunge band Nirvana.
Grohl admitted that his hearing hadn’t been tested by a doctor in many years – mainly because, he said, “I know what they’re going to say: ‘You have hearing damage, tinnitus in your left ear, more than your right ear.'”
Grohl maintains that he can still hear certain frequencies well, so when mixing an album in the studio, he can still hear if something is slightly out of tune, or “if a cymbal isn’t bright enough…in the mix, I can…hear the details of everything we did with this song.”
However, voices, especially in crowds, restaurants or even at the table, are more difficult for Grohl: “Even if you were sitting right next to me, I wouldn’t hear a [single] word you said to me all the time.” Wearing a mask during the pandemic has made things worse for him, he said, because he can no longer read lips.
Despite his hearing loss, Grohl refuses to wear headphones when performing on stage; he says they distort his spatial experience of music. He’s been using the same sound mixer for over 31 years and he knows what everything sounds like. Finally, he claims that he has “little ear holes” and the earbuds frequently pop out of his ears. Plus, he doesn’t like that wearing ear protection makes him look like “a praying mantis…I want to go out and go crazy,” he said.
NIHL is caused by exposure to excessively loud sounds. It can be a one-off exposure to a very loud sound, an explosion or a pulse, or it can happen when loud sounds are felt for a long time. Hearing loss may be immediate or may take a long time to be noticeable. It can be temporary or permanent and can affect one ear or both ears.
According to CDC estimates, about 10 million to possibly as many as 40 million adults under age 70 in the United States have hearing test results that suggest NIHL. Additionally, an estimated 17% of young people between the ages of 12 and 19 may have an NIHL in one or both ears.
Exposures that increase the risk of NIHL can be occupational and/or recreational. The National Institute for Occupational Safety and Health (NIOSH) monitors industries where there is a higher risk of NIHL and makes recommendations to reduce the risk to these workers, including the following:
Recreational activities that increase the risk of NIHL include target shooting and hunting, snowmobiling, listening to MP3 players at high volume through earphones or headphones, playing in a band, and attending loud concerts. Woodworking tools can also be a source of loud sounds.
Sound and Hearing 101
Sound is measured in decibels (dB) and is a measure of loudness. It can be measured in two ways:
- By frequency, the number of sound waves per second. This corresponds to the pitch of a sound as we perceive it. The high frequency is high-pitched, like a child’s voice; and the low frequency is serious, like a growl
- By amplitude, the amount of pressure produced by a sound wave. This is perceived as the volume of a sound
It is important to note that decibels increase either logarithmically or exponentially. Therefore, an increase of 10 to 20 dB is actually 100 times stronger!
According to data from the National Institute on Deafness and Other Communication Disorders (NIDCD), here are some common sounds and their average decibel range:
- Normal conversation: 60-70 dB
- Cinema sounds: 74-104 dB
- Motorcycles/mountain bikes: 80-110 dB
- Headphone music at maximum volume: 94-110 dB
- Sporting events and concerts: 94-110 dB
- Fireworks show: 140-160 dB
Sounds at or below 70 A-weighted decibels (dBA), even after long exposure, are unlikely to cause hearing loss. However, prolonged or repeated exposure to sounds at or above 85 dBA can cause hearing loss. The louder the sound, the shorter the time it takes for the NIHL to occur.
Sound waves entering the ear canal cause the tympanic membrane to vibrate. The vibrations are transmitted to the three small bones of the middle ear (hammer, incus and stirrup) which amplify the vibrations and transmit them to the adjacent cochlea.
The snail-shaped cochlea (or inner ear) contains a group of interconnected fluid-filled chambers. An elastic septum, the basilar membrane, crosses the cochlea and begins to undulate when its fluid vibrates.
The basilar membrane is lined with sensory cells, called hair cells, named after the stereocilia that cover them and protrude into the cochlear fluid. The bending of the stereocilia causes the opening of pore-like channels, located at the ends. When this happens, chemicals rush into the cell, creating an electrical signal that is transmitted to the auditory nerve.
Most NIHL is caused by the damage and eventual death of hair cells. Unlike the hair cells of birds and amphibians, human hair cells are unable to regrow. The damage is permanent.
What are the effects and signs of NIHL?
Exposure to loud noise for an extended period of time can cause gradual hearing loss. However, because the changes are slow, they often go unnoticed or ignored until they become pronounced. Sounds can become muffled or distorted and it can be difficult to understand speech, especially in crowded or noisy rooms. Often loved ones complain that a person with NIHL has turned up the volume on their television or radio.
Exposure to loud noise can also cause tinnitus – a buzzing, buzzing, or roaring sound in the ears or head. Tinnitus may subside over time, but may become continuous or intermittent throughout a person’s lifetime. Hearing loss and tinnitus can occur in one or both ears.
Exposure to loud impulsive or continuous noise can cause temporary hearing loss that resolves within 16 to 48 hours. Recent research, however, suggests that even if hearing loss seems to go away, there may be residual long-term hearing damage.
According to the CDC and NIDCD, hearing loss caused by exposure to loud sound is preventable. To reduce the risk of NIHL, they recommend adults and children do the following:
- Understand that NIHL can cause communication and learning difficulties, pain or ringing in the ears, distorted or muffled hearing, and inability to hear certain environmental sounds and warning signals
- Identify sources of loud sounds (such as gas-powered lawn mowers, snowmobiles, power tools, gunshots, or music) that may be contributing to hearing loss and try to reduce exposure
- Have your hearing evaluated by a licensed audiologist or other qualified professional, especially if you are concerned about possible hearing loss
- Adopt behaviors to protect hearing: (1) Turn down the volume of music systems; (2) Move away from the source of loud sounds when possible; and (3) Use hearing protection devices when exposure to loud sounds cannot be avoided or reduced to a safe level.
NIHL among musicians
Overexposure to sound, both in intensity and duration, is common among musicians. This not only includes performers, but also orchestral musicians, music teachers, conductors, DJs and sound engineers.
NIOSH has received several requests for assistance in measuring and mitigating exposures from several of the above groups. For example, the agency prepared a health risk assessment report for elementary and secondary school music classrooms, as well as a Workplace Solutions document: “Reducing the Risk of Hearing Disorders Among Musicians “.
NIOSH recommends that employers, concert hall operators, schools and colleges consider the following actions to reduce potential hearing damage for musicians, music teachers and students, and other exposed workers:
- Encourage participation in education and awareness campaigns on music-induced hearing loss
- Perform regular sound level assessments to determine if levels exceed 85 dB
- If sound levels are above 85 dB, implement a hearing loss prevention program that includes annual hearing tests and training
- Identify the hearing protection solutions that work best for the individual musicians or workers involved. Consider modifying the workspace, such as adding sound-absorbing materials to the walls or using rooms with higher ceilings for brass or percussion instruments
Musicians should consider taking the following actions:
- Monitor the level and duration of exposure to musical sounds. If no professional sound measurement equipment is available, some smartphone apps can provide useful and accurate information about sound levels
- Play music at lower levels during individual and group rehearsals, whenever possible
- Get an annual hearing evaluation from a licensed audiologist
- Give the ears a little rest; take breaks in quiet areas when possible
- Wear hearing protection if necessary; some hearing protectors are made and targeted specifically for musicians
Michele R. Berman, MD, is a pediatrician turned medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children’s Hospital. Its mission is both journalistic and educational: to report on common diseases affecting uncommon people and to summarize the evidence-based medicine behind the headlines.