The cochlea is a small, fluid-filled, ice cream swirl-shaped structure in the inner ear. Its inner canals are covered in tiny hair cells. After sound travels through the outer and middle ear, converting from acoustic to mechanical energy, it reaches the cochlea. The mechanical energy from the middle ear bones converts to hydraulic energy when it creates pressure waves on the inner ear fluid of the cochlea. The fluid puts pressure on the tiny hair cells, which activate the auditory nerve. It is at that point that the final conversion of energy occurs, from hydraulic to electrical. The electrical impulses are sent to the brain and interpreted as information.
Like other organs in the body, the cochlea performs an astonishing and uniquely human function. However, unlike other organs in the body, when surgery is performed on the cochlea there is limited concern for bodily rejection.
There is a common misconception that cochlear implants are like eyeglasses. An implant allows you to hear, much like glasses allow you to see. However, the important distinction is that cochlear implants have direct interaction with the brain. As Humphries et. al. (2012) state, cochlear implants involve not only progression in technology, but the biological interface between technology and the human brain. And, while the equipment itself may function perfectly, there is no way to predict the reaction of a child’s brain to the technology.
The intentional disregard for this crucial fact is the most dangerous mentality. This type of blatant overlook is not typical with other surgeries, for obvious reasons. When a pacemaker is placed, the recipient is educated extensively on the potential complications, including failure of the device. When an organ is surgically replaced, the chance of the body rejecting the new implant is openly discussed. Recipients of surgically implanted prostheses of any kind are always informed of the risks of failure or rejection. They are never informed that their artificial structures are seamless replacements for the original organ.
We owe it to implanted children to do the same when educating their parents. Because a child’s brain is still developing and learning language, device rejection or failure of any kind can result in stunted brain development and language deprivation. Parents must be informed that it is still impossible to know how a child’s brain will react to the implant. Because of this, cochlear implants are not sufficient as a standalone approach for language intervention (Kral et. al, 2016). Implanted children must be taught sign language as a preventative measure to ensure proper brain development.
A cochlear implant is a man-made device that is surgically implanted. Just as a pacemaker does not replace the function of the heart, a cochlear implant can never fully replace the function of the cochlea. And just like a pacemaker, its recipients must be properly educated about the repercussions of its potential rejection.