Negative Effects of Headphone Usage
Cheri Moore
University of Missouri Saint Louis
Social Work Master’s Program
November 3, 2013
What kind of damage do headphones and earphones cause to the inner ear and to the auditory processing systems? The effect of “recreational listening” or “sound exposure” refers to amplified sound delivered through all forms of technology (1). Research has and continues to focus on the potential for temporary and gradual damage to one’s hearing as changes in technology continue to shape listening behaviors through the use of headphones, earphones, and portable devices such as MP3 players and iPods by teens and young adults. Numerous research studies found hearing loss among young people throughout the world, caused not only by listening to amplified sounds at a high volume, but also at a normal volume with prolonged listening in excess of seven hours a week (1). Most interesting was Harrison’s emphasis that speech dysfunction characteristics indicated problems within the auditory system; however, auditory testing solely relying on air conduction testing could be normal (1). Characteristics such as the inability to comprehend what a person says or the need to ask for information to be repeated may be caused by an auditory disability (1). Dr. Berard shared in his book, Hearing Equals Behavior, that characteristics of hearing loss may be explained by dysfunctional neurological responses affecting what the brain does with what is heard (2).
Evidence of concern regarding hearing loss due to headphone use is reflected throughout the world leading to the completion of studies in countries such as Canada, Israel, Korea, and the United States involving young people, teens, and adults through their early thirties (3,4,5,6). The results of these studies consistently confirmed the possibility of temporary and permanent hearing loss with headphone or earphone usage. The Canadian study found 3.2 {77d4898647b49139da30a0a7cc2019467f6d4a05f71893f9a5ca5bcca7b450f1} of participants were at risk because they maxed out their volume on their personal listening devices (3). The Israeli study found 25{77d4898647b49139da30a0a7cc2019467f6d4a05f71893f9a5ca5bcca7b450f1} of participants were at risk when there were high levels of background sound, because they turned up their personal listening devices to cover up background sound (4). A unique finding within the Korean study discovered all students, ages 13 to 17, which had used their portable listening device for over five years were too tolerant to sound (5). The greatest danger to increased tolerance of sound is the person’s failure to recognize dangerous listening levels; thus, increasing their risk for hearing loss (5). This emphasizes the importance of passing legislation limiting decibel output capabilities of portable players with earphones in addition to developing educational programs to prevent the development of poor listening habits among young people.
Research studying the negative effects of listening with earphones or headphones to music on portable players used Canada’s guidelines of “85 decibels, established by Canada’s center for Occupational Health and Safety (OSHA) to prevent hearing loss in the workplace as the maximum volume setting for safe listening (3, p.4227; 6, p. 1472; 7 p. 2756; 8, p. 646). According to Margaret Kenna, the National Institute for Occupational Safety and Health (NIOSH) in the United States uses the same guidelines established by OSHA and mandates use of ear protection devices when workers are exposed to sounds louder than 85 decibels (2007). These guidelines were established to protect people in the workplace and in public places of entertainment from “noise-induced” hearing loss; now the term “noise-induced” also applies to listening devices with headphone or earphone usage (1, 9).
Research shows many risk factors associated with the use of earphones when listening to music on portable listening devices. A review of existing legislation restricting decibel output capabilities of personal players with earphones is presented to the reader. Evidence-based research reveals significant findings explaining why today’s earphones and portable listening devices are increasing the risk of hearing loss. A review of people’s listening habits and influences of environments on listening volumes along with improvements in technology found evidence showing that these three factors compound each other leading to higher risk factors of hearing loss. Evidence was found showing that the type of earphone used with portable listening devices can cause unsafe listening levels. I believe the overwhelming evidence found should propel people to educate others and pass laws. More work needs to be completed to research
the extent of harm caused by earphone and headphone usage with personal listening devices upon the physical structures of the ears as well as upon the neurological development of the auditory processing center.
Literature Review
According to Keith, Michaud, and Chiu only France has created legislation limiting the maximum volume output of all personal stereo systems and portable players with headphones (sold as a unit) to 100 decibels (dB) (3). According to Harrison, a Finnish study completed by Jokitulppo, Bjork, and Akaan-Penttila found the maximum volume range of personal music players to range from 78 to 136 decibels (1). I believe a range this wide can cause confusion when determining safe volume settings. Keith found portable players with certain types of earphones reached a volume of 107 decibels (3). This is equally concerning, because OSHA guidelines indicate sound at this volume will damage hearing. At the time of this publication, January/February 2011, Kahari and Olsson reported laws similar to those in France were being established in other countries in Europe with discussion also focusing on even lower decibel limits of 80 decibels for portable music players designed for children. These laws will require manufacturing companies to invest in the creation of new technology and software to sell listening devices within Europe. Unfortunately, there are no recognized industry standards, legislation, or guidelines restricting decibel output for portable music players with earphones in the United States (10). The only guidelines, which are not widely taught or known by young people, are NIOSH’s industrial guidelines for decreasing one’s exposure to harmful environmental sounds. These guidelines are: for every three decibel increase in volume with a baseline of 85 decibels, NIOSH recommends a decrease in listening time by half (9). For example, eight hours of listening at 85 decibels is considered safe, but only four hours of listening at 88 decibels is considered safe (9). The listener can only listen safely to sound for two hours at 91 decibels (9). All researchers used OSHA guidelines of 85 decibels to discuss possible harm or lack of harm while listening with earphones or headphones to music. As listening habits are reviewed below, it is important to remember that recommended listening time above 92 decibels would be zero minutes, because it would be harmful.
A study completed in the United States of America focused on people’s reactions to background sound while listening to their personal listening player wearing earphones. Significant evidence was found showing that all participants chose louder listening levels in the presence of loud background sounds with an average range of 68 to 75 dB with peaks exceeding 110 dB as opposed to lower listening levels in a quiet environment averaging 58 dB with a peak of 87 dB (6). A similar study conducted in Canada found statistically significant evidence concluding that young people who used earphones with their personal listening devices increased their listening volume as background sounds became louder (11). Epstein also noted that music, as opposed to environmental stationary noise, is “highly kurtotic” and emphasizes the known fact that kurtotic noise causes sensorineural hearing loss (6). Sensorineural hearing loss occurs when there is damage to the hairs in the inner ear. I believe long-term research needs to be conducted to determine the validity of using OSHA guidelines when determining how loud a person may safely listen to music through earphones or headphones. These studies support the possibility that earphone usage may cause damage to the inner ear, because listeners chose volumes exceeding 85 decibels to cover up background sounds. This study found an increased risk for hearing loss depends on a person’s listening habits in different environments.
Compounding this issue is the availability of different types of headphones and earphones. Significant evidence was found showing that tighter fitting earphones as opposed to over the ear headphones increased sound transfer from the portable player to the ear by as much as seven to nine decibels (5). Keith studied the effect of tight earphone usage with nine different digital audio players and found significant evidence averaging an increase of sixteen decibels when used instead of loose fitting earphones, surpassing safety limits of 85 decibels set by OSHA with decibel levels reaching 101 to 107 decibels (3). Likewise, Epstein, Marozeau, and Cleveland discovered most personal players bought with prepackaged earphones do not provide sufficient quality to protect users from background noise; thus, causing a significant increase in volume by the user (6). Listening levels may be lowered by purchasing sound-isolating headphones and earphones which will filter out background sounds, but listeners still need to be educated about developing safe listening habits. One must remember that the ability to hear background sounds helps keep us from harm. Due to advances in technology and the prevalence of poor listening habits among young people, legislation needs to be passed in the United States restricting volume output of personal listening devices with quality earphones on an industry level and prevention programs need to be more widely publicized.
One may wonder why this concern was not addressed when personal listening devices and earphones were first invented. According to Keith, Michaud, and Chiu, there are four studies, from 1996 through 1998, accessing the impact of portable compact disc players upon listening habits, which discovered subject’s listening times were minimized due to the bulky size of player, short battery life, and limited song capacity (p. 4227). In comparison, today’s portable audio players are easy to transport, have a lengthy battery life, and large song capacities, which when combined with high performing earphones, engage listeners for longer periods of time with potentially louder maximum sound capacities (3). These variables all increase the risk factors of hearing loss due to prolonged, loud sound exposure to music (3 ). Guidelines established by OSHA for environmental sounds may not provide enough protection for users of personal listening devices with earphones due to prolong listening capabilities and the kurtotic nature of music. Research is generating an awareness of the numerous factors contributing to the increased risk of hearing loss revolving around earphone and headphone usage with personal portable players
According to Harrison, evidence of the danger of hearing loss may have been found in a study completed in China by Peng JH, Tao ZZ, and Huang ZW where 14{77d4898647b49139da30a0a7cc2019467f6d4a05f71893f9a5ca5bcca7b450f1} of 120 young people in the study experienced a temporary hearing loss exceeding 25 decibels when given an air conduction test after listening times were increased while using personal listening devices with earphones (1, p.380). According to the prolific otolaryngological research of Dr. Harrison, temporary hearing loss is recognized in the audiology community as a temporary threshold shift (TTS), and that repeated TTS experienced by an individual may possibly cause permanent changes within the inner ear, thecochlea, and ultimately cause hearing loss (1). Some audiologists believe hearing is being damaged by the repeated use of headphones and earphones. Gu Kim assessed the frequency of TTS by conducting a mixed methods study assessing preferred listening volumes of students 13 to 18 years of age, comparing males and female as well as comparing data based on years of listening (5). Significant evidence was found showing that male students listened to music approximately three decibels louder at 4000 Hertz than female students; thus, showing a higher threshold shift level (5). Significant evidence was also found showing students 13 through 15 years of age listened to music louder than students who were 17 and 18 years of age; thus, revealing higher risk behavior with younger students (5). Higher risk behavior can increase the frequencies of TTS, which will increase the risk of hearing loss. Most concerning were Gu Kim’s findings that students who used personal listening devices for more than five years showed significant preferences for higher listening volumes than students who did not use personal listening devices (5). Needing to listen to music at a louder volume provides additional evidence showing the presence of a permanent threshold shift, which is an indication of hearing loss.
Developing Safe Listening Habits
There are numerous prevention options available for parents to help them protect their child’s hearing. Parents may download software from www.support.apple.com onto their child’s Apple iPod Nano or their Fifth Generation iPod; this enables parents to set a maximum volume limit and lock the personal listening device. Dr. Harrison encourages parents to teach their child how to protect their hearing as well as the consequences of hearing loss by playing with their child or teen on two interactive computer websites called Dangerous Decibels (www.dangerousdecibels.org) and Sound Sense (www.soundsense.ca) (1). Parents can also encourage their child’s school to purchase an educational program called “Sound Sense” (1). All teens 12 to 18 years of age in a qualitative, focus group study did not object to warning labels being put on MP3 players, but they also did not believe warning labels would cause people to change their listening habits and use safer listening volumes (12). Young people in this study group also shared that they would purposely look for a personal player that did not limit their choice of volume and would not buy one restricting their choice of volume (12). The results of this study validate the need for laws regulating the production of earphones and personal listening devices. I also believe free educational material will need to be included with these new personal listening devices to help people accept the regulations and change their listening behaviors.
Dr. Harrison states that each person is born with a specific number of cochlear hair cells in their inner ear, and when hair cells are damaged it prevents them from transmitting enough sound (1). When hair cells die they are not replaced; cochlear hair cells do not regrow (1). Noise-induced hearing loss usually leaves the nerve (hair) cells damaged rather than dead; they typically bend and may break (1). Thus, hearing aids are a viable option for teens with noise-induced hearing loss, because they amplify enough sound to transmit energy across bent hair cells and provide the additional stimulation necessary for hearing (1). I believe air conduction tests given by license audiologists as part of a young person’s physical would offer an additional, effective prevention program against noise-induced hearing loss.
I recommend people learn different ways to enjoy listening to their music out in the room. This can be accomplished by using an iPod dock, wearing an armband designed to hold an iPod, and by plugging an iPod into an automobile’s stereo system or computer. According to Dr. Fligor, if people chose to listen to music through earphones, they should use sound-isolating earphones to prevent users from increasing volumes on their personal players when background sounds become louder (9). However, I encourage you to remember there is no research showing that the use of sound-isolating earphones changed people listening habits in noisy environment resulting in lower listening volumes. Dr. Fligor advises people to listen to music on their personal listening devices no louder than 60{77d4898647b49139da30a0a7cc2019467f6d4a05f71893f9a5ca5bcca7b450f1} of the player’s potential output and to limit their listening time to no more than an hour and a half each day (9).
Hearing is an integral part of everybody’s life and should be fiercely protected. Professionals and parents should advocate for the child or young person who cannot advocate for themselves. Society needs to acknowledge a profound statement written by Dr. Kenna, which when summarized essentially states that hearing loss occurs so gradually that once it is severe enough to be measurable; it is too late to reverse (9). It is imperative to create and pass laws to protect hearing by regulating decibel volume output capabilities of personal listening devices, including earphone output (3, 4). This need is validated by a study that found students 12 to 18 years of age revealed they were not personally motivated to lower their listening volumes, even after parents had warned them about possible hearing loss, because they did not internalize the consequences (12). I believe the best solution to ensure that young people are protected is the implementation of educational programs and the passing of laws. Schools need to teach safe listening habits by incorporating hearing conservation programs into their health curriculum and using educational materials such as Sound Sense. Homework should also be sent home requiring parents to use the web-based program called, Dangerous Decibels, to encourage discussion and role modeling in the home (1). This will benefit young parents in their twenties and early thirties who used MP3 players and iPods during their teen years with earphones that exceed safe listening volumes (6, 11). Due to the relative newness of personal listening devices, the long-term consequences of earphone and headphone usage with personal listening devices will not be known for another twenty or more years (10). However, existing research clearly shows it is vital to prevent “noise-induced” hearing loss in young people because once these hair cells are destroyed, it is permanent and the consequences are numerous and life-long (5). The best way to protect your hearing is to listen to music out in the room using safe listening levels.
References
- Harrison, R. (2008). Noise-induced hearing loss in children: A ‘less than silent’ environmental
danger. Paediatrics & Child Health, 13(5), 377-382.
- Berard, G. (1993). Hearing Equals Behavior. New Canaan, Connecticut: Keats Publishing.
- Keith, S., Michaud, D., & Chiu, V. (2008). Evaluating the maximum playback sound levels from portable digital audio players. Acoustical Society of America, 123(6), 4227-4237.
- Muchnik, C., Amir, N., Shabtai, E., & Kaplan-Neeman, R. (2012). Preferred listening levels of personal listening devices in young teenagers: self reports and physical measurements. International Journal of Audiology, 51, 287-293.
- Gu Kim, M., Min Hong, S., Joon Shim, H., Doe Kim, Y., II Cha, C., & Geun, Y. (2009). Hearing threshold of Korean adolescents associated with the use of personal music players. Yonsei Medical Journal, 50(6), 771-776.
- Epstein, Ml, Marozeau, J., & Cleveland, S. (2010). Listening habits of iPod users. Journal of Speech, Language, and Hearing Research, 53(6), 1472-1477. doi:10. 1044/1092- 4388(2010/09-0059).
- Keith, S. E., Michaud, D. S., Feder, K., Haider, I., Marro, L., Thompson, E., & Marcoux, A. M. (2011). MP3 player listening sound pressure levels among 10 to 17 year old students. The Journal of the Acoustical Society of America, 130(5), 2756-2763. doi:10.1121/1.3641406.
- McNeill, K., Keith, S. E., Feder, K., Konkle, A. T. M., & Michaud, D. S. (2010). MP3 player listening habits of 17 to 23 year old university students. The Journal of the Acoustical Society of America, 128(2), 646. doi:10.1121/1.3458853.
- Kenna, M. A. (2008). Music to your ears: Is it a good thing? Acta Pædiatrica, 97(2), 151-152. doi:10.1111/j.1651-2227.2007.00655.x
- Kahari, K., Aslund, T., & Olsson, J. (2011). Preferred sound levels of portable music players and listening habits among adults: A field study. Noise & Health, 13(50), 9-15.
- Hodgetts, W., Rieger, J., & Szarko, R. (2007). The effects of listening environment and earphone style on preferred listening levels of normal hearing adults using an mp3 player. Ear & Hearing, 290.
- Vogel, I., Brug, J., Hosli, E., Van Der Ploeg, C., & Raat, H. (2008). Mp3 players and hearing loss: Adolescents’ perceptions of loud music and hearing conservation. The Journal of Pediatrics, 400-404. doi: 10.1016/j.peds.2007.07.009
- Dreossi, R., & Momensohn-Santos, T. (2005). Noise and its interference over students in
a classroom environment: literature review. Pro-Fono Revista de Atualizacao Cientifica,
Barueri (SP), 17(2), 251-258.
- Faculty of Medicine & Dentistry at the Univ. of Alberta. (2011). Human brain development does not stop at adolescence: Research. University of Alberta Faculty of Medicine & Dentistry,
- Fligor, B., (2009). Personal listening devices and hearing loss: seeking evidence of a long term problem through a successful short-term investigation. Noise and Health, 11(44),
129-131.