Hearing Damaged by Headphone Use

Summary
Researchers have found that listening to music through portable music systems by plugging in earphones may be convenient, but comes with health hazards. This study attempts to identify the impact that such loud music could have on a person’s hearing. Tests conducted revealed that while basic hearing function is unaffected, there is loss of ability to discard unwanted frequencies, which leads to reduction in the clarity of hearing. Also, this problem is a significant indicator of possible hearing difficulties in the future.

Introduction
A by-product of present-day lifestyle is the lack of time for recreational activities, such as music. Many individuals, specifically those from the younger generation, compensate for this loss by listening to music with the help of earphones while at work or while traveling. It has been found that in an environment with a high noise level, the person inadvertently tends to play very loud music. This could lead to damages in auditory perception. The neurons that weed out unwanted frequencies are affected and so, the sharpness of fine-tuned listening is diminished. Although the overall listening capacity is not affected, the quality of sound perception is reduced.

Methodology
* Participants were designated into two groups — the ‘‘exposed’’ group and the “control” group, each consisting of 13 subjects.
* The first group was habituated to listening to music through portable music players for over 2 years while the control group was not.
* Behavior–related data and hearing capacity were measured in two conditions — distracted and focused hearing. Statistical analysis was done to evaluate the differences between the auditory capacities of both groups.

Results/Key Findings
* The basic hearing tests reported no differences between the exposed and control groups in hearing ability, particularly in focused condition.
* In the exposed group, however, the response in the distracted listening test was late and of less amplitude, as compared to the focused condition.
* This study proves that the playing of loud music into earphones on portable music players could adversely impact the range of audible frequencies in the auditory cortex.  Overall hearing remains good, but the clarity of hearing is affected.

Next Steps/Shortcomings
The current study showed that listening to loud music in earphones causes harm to the hearing apparatus by weakening the neurons that filter out unnecessary frequencies. This finding was more valid when the participants were given a distracted environment for the test, where more hearing precision is required. Still, further research is warranted to zero in on the exact area of the problem where the widening of frequency tuning occurs.

Conclusion
Listening to music on earphones more often than required, not realizing the high decibels in a noisy atmosphere, damages the auditory organs to some extent. Although there is no variation observed on regular hearing tests, more sensitive tests show adverse effects. There is a set of neurons that aid the auditory neurons in cutting out harmful or unwanted frequencies. This mechanism is affected by loud vibrations so all frequencies start becoming audible. This leads to loss of quality in sound perception. The same aspect has been linked with tinnitus. Thus, it is important to spread awareness about such side-effects of loud music in earphones among young people to check the habit of listening on earphones.

For More Information:
Misuse of Portable Music Player Causes Disturbances in Human Auditory Cortex
PLoS ONE, March 2011
By Hidehiko Okamoto; Henning Teismann
From the National Institute for Physiological Sciences, Okazaki, Japan and Westfalian Wilhelms-University Muenster, Muenster, Germany

*FYI Living Lab Reports Are Summaries of the Original Research.