Cochlear Implant in India
What is Cochlear Implant ?
A cochlear implant (CI) is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing.
Cochlear implants may help provide hearing in patients who are deaf because of damage to sensory hair cells in their cochleas. In those patients, the implants often can enable sufficient hearing for better understanding of speech. The quality of sound is different from natural hearing, with less sound information being received and processed by the brain. However, many patients are able to hear and understand speech and environmental sounds.
Basic research
In 1961, G von Bekesy (1899-1972) received the Nobel Prize for demonstrating that sounds trigger vibrations of the basilar membrane which spread from the base to the apex of the cochlea in the form of longitudinal waves; peaks occur at various points depending on the frequency, resembling the keys of a piano, with low frequencies towards the apex and high frequencies towards the oval window. The terms "cochlear keyboard" and “cochlear tonotopy” are often used to describe these phenomena.
In 1975, EF Evans showed that each sensory afferent fiber of the cochlear nerve handles a specific frequency, making it electively sensitive to a very narrow frequency band.