Light-wave implant for the hearing impaired

As we learned in class, different nerves can be stimulated by stimuluses that aren't intended for them. Similar to occular nerves producing random bright spots when exposed to pressure, auditory nerves can be stimulated with light. This is by no means an easy task, however.

Researchers at Northwestern University have found that shining light at a guinnea pig's auditory nerves produced a greater response at the relay between the inner ear and the brain (much better than cochlear implants).

The norm for implants for hearing impaired is a cochlear implant which can only stimulate around 20 out of over 3000 auditory sensors. This clearly means that hearing scope will be limited in sensitivity. But by using IR light, sensors can pinpoint better more of those auditory nerves. This will allow an individual to pick up different frequencies of sound over a broader range much better, giving them an overall better scope of hearing.

One of the most interesting things about this, and also most difficult things, is the idea behind converting one type of stimulus into another. Since the auditory range of the human body is quite large and complex, understanding how to essentially translate the language of light into the language of sound, and do so in a way that allows the body to understand this translation. Simple intensity increases probably won't be enough since auditory nerves sense both frequency and amplitude of a signal. Obviously this is a difficult task.

If researchers can just correlate light signals to a corresponding auditory signal, and ensure that the auditory nerves pick it up in the same way, the rest will be easy.

http://news.bbc.co.uk/2/hi/health/7737307.stm