Short term hearing loss a protective mechanism
After excessive noise exposure, short term hearing loss (temporary hearing loss) is the body’s way of protecting itself and coping with the loud noise, according to study.
The study revealed a physiological adaptation mechanism that allows the cochlea to perform normally when exposed to heavy noise.
A measure to adapt
Professor and lead author of the study Gary Housley from the University of New South Wales and his research colleagues from the University of Auckland and the University of California found that cells in the cochlea release a hormone named ATP as sound levels rise. This in turn causes a temporary reduction in hearing sensitivity.
"It may explain why we lose our hearing for hours or days after we have been exposed to a rock concert or listen to music at high levels using our personal music players," said Housley.
"Our research shows that the ear can adapt to high noise levels and keep operating. But there is a catch - because our hearing adjusts, we think the sound has a lower volume than it actually has and we can easily exceed the capacity of the ear,” Housley added.
Only protective in small doses
However, researchers warn that this defence mechanism cannot guard against continual high-frequency exposure to noise.
"It's like sun exposure. It's not the acute exposure, but the chronic exposure, that can cause problems years later," explained Housley.
They are hoping that their results may help them in finding new ways to better protect the ear against noise in loud surroundings.
The research was published in the scientific journal Proceedings of the National Academy of Sciences (PNAS).
Sources: http://www.sciencedaily.com and http://www.theaustralian.com.au