Monday, November 30, 2015

Go Ahead and Turn Up Your Music



As most of us know, blasting loud music can damage your hearing, but researchers at Rockefeller University may have found the solution. But first, lets have a small refresher on how loud music can damage our ears.

Sound waves are a form of energy that are collected and funneled by our auricles and travel down our external auditory canal to strike the tympanic membrane. The vibrations from the tympanic membrane in turn vibrate the auditory ossicles and transfer the energy to the oval window. The oval window then transmits the pressure waves down into the fluid filled, scala vestibuli. Finally, the waves go through the cochlear duct to vibrate the basilar membrane and cause the hairs on inner hair cells to move.  Movement of those hairs cells causes neurotransmitters to be released and an action potential is generated. That action potential is transmitted to the brain where it makes sense of those sweet Bieber tunes.

The one downside to this wonderful system is that loud noises, prolonged exposure to loud music, and just growing old can damage or destroy those inner hair cells. Here’s the kicker; they don’t grow back and once they’re gone and you’ll be left with only the memories of sounds.

This is where Ksenia Gnedeva’s research at Rockefeller University can save the day.  Her team discovered two genes that are crucial for hair cell growth and proliferation within the utricle of newborn mice. Newborn mice, like newborn people, also stop producing inner ear hair cells just after birth. They found that those genes, Sox4 and Sox11,  (both transcription factors) were down regulated at the end of hair cell proliferation. The next question then is what happens when you up regulate them in adult mice? Well, Ms. Gnedeva’s team did just that and found they were able to not only restore hair cell function but also to generate new hair cells. These are of course in vitro studies but the findings are very promising for all of us on the road to hearing loss and those who are deaf.



No comments:

Post a Comment