If you have ever been exposed to a sudden loud sound that caused your ears to ring and everything sounded muffled for a little bit then consider yourself lucky. If that sound had been a little bit louder it might have caused changes to your ability to hear that would have been permanent and irreversible. At least that was the general consensus until the results of the following study were released.
The increasingly common use of improvised explosive devices, or IEDs, around the world provided the impetus for a new study, funded in part by the U.S. Department of Defense. Researchers from Stanford University School of Medicine, led by senior author John Oghalai used a mouse model and determined that loud blasts actually cause hair-cell and nerve-cell damage, rather than structural damage, to the cochlea, which is the auditory or hearing portion of the inner ear.
“The theory now is that if the ear could be treated with certain medications right after the blast, that might limit the damage. Much of the resulting hearing loss after such blast damage to the ear is actually caused by the body’s immune response to the injured cells, Oghalai said. The creation of scar tissue to help heal the injury is a particular problem in the ear because the organ needs to vibrate to allow the hearing mechanism to work. Scar tissue damages that ability. There is going to be a window where we could stop whatever the body’s inflammatory response would be right after the blast,” Oghalai said. “We might be able to stop the damage. This will determine future research.”
This could be good news for the millions of soldiers and civilians who suffer long-term hearing damage as a direct result of exposure to a sudden loud noise.