It seems like nearly everyone you encounter, from kids to seniors, is constantly interacting with their cell phone, computer, MP3 player, game console, e-book reader or tablet computer. And while it may be the social norm now, scientists and researchers are watchful to figure out whether our hypeconnectivity could have adverse effects on our health.
A recent study by scientists from the University of Leicester found that listening to high volume on your headphones can damage the coating of nerve cells in your ears, causing temporary deafness. While it depends on the type of headphones you use, how loud and how often you use them, you could be subjecting your ears to noise levels similar to that of a jet engine.
The study showed that exposure to loud noises 110 decibels and higher can strip the cells of a coating within our ear called the myelin sheath, which helps the electrical signals travel along the cell. The excessive noise disrupts the electrical signals which means the nerves can’t efficiently transmit information from the ears to the brain. So if you’ve ever turned your iPod up near maximum volume for extended periods of time , you’ve likely been listening to your music at 110 decibels, the same noise level as a jet engine.
Sound is measured in decibels and it may surprise you how some of your daily activities may be noisier than you think. Here are some decibel levels of common sounds:
- Firecracker: 150 dB
- Ambulance siren or airplane taking off: 120 dB
- Nightclub: 120 dB
- Jet engine: 120+dB
- Movie theatre: up to 117 dB
- Rock concert: 110-125 dB
- Listening to music with headphones: 105-120 dB if the volume is cranked up to the maximum setting (earbuds, which you insert directly into your ear, can add 6-9 dB to the volume)
- Motorcycle: 95 dB
- Noisy restaurant or heavy traffic in the city: 85 dB
- Normal conversation: 60 dB
- Fridge humming: 40 dB
- Whispering: 30-15 dB
Believe it or not, being exposed to anything louder than 85 dB for extended period of time can cause permanent hearing loss and it’s often irreversible. Also, an occasional loud noise may cause you less loss then extended exposure of a much quieter sound. For example, 8 hours at 85 dB causes as much damage as 4 hours at 88 dB, 2 hours at 91 dB, or just 15 minutes at 100 dB.
However, the study also showed for the first time that the coating surrounding the nerve cells can reform, letting the cells function again as normal. This means hearing loss can be temporary, and full hearing can return, the researchers said. In an article by Science Daily, Dr Hamann explained:
“We now understand why hearing loss can be reversible in certain cases. We showed that the sheath around the auditory nerve is lost in about half of the cells we looked at, a bit like stripping the electrical cable linking an amplifier to the loudspeaker. The effect is reversible and after three months, hearing has recovered and so has the sheath around the auditory nerve…The work will help prevention as well as progression into finding appropriate cures for hearing loss.” Read More…
The new research could lead to the first drug treatments to prevent the development of tinnitus (ringing in the ears)and/or cures to hearing loss but it is still an ongoing project. Regardless, we should always protect our ears, limit our headphone use and keep the volume below sixty percent.