How do Cochlear Implants work
A cochlear implant is an artificial, electronic replacement for the malfunctioning parts of the natural ear. While it cannot match the quality of natural hearing, an implant comes very close to restoring or establishing natural hearing in a hearing impaired person. Cochlear implants consist of a set of external components and internal components. The external components consist of a microphone, a battery, magnet, radio frequency transmitter and a sound processor. The processor converts the surrounding sounds into signals that can be transmitted to the internal components, which contain a receiver/stimulator, a micro-computer, radio antenna, magnet and an electrode array. The magnets are of reverse polarity to hold the external component in place over the internal components. The internal and external parts communicate digitally through the radio frequency devices.
Despite the variances among the brands, the fundamental functioning of cochlear implants is the same. The microphone on the outside serves to pick up sounds. The level of sounds that can be picked up depends on the quality of the microphone. The more sensitive it is, the higher the quality of the sound. Next, the speech processor filters and analyzes the sounds that are picked up by the microphone. Usually speech is given a higher priority over other sounds. The sounds are converted into signals and are sent to the transmitter. The transmitter works just like a radio and sends the signals, in fact as FM radio signals, to the cochlear implant i.e. the internal component. Once the signals are received, they are decoded and corresponding electrical signals are sent to the array of electrodes that are in the implant under the skin. The electrodes, depending on the electrical energy that they receive stimulate the auditory nerve that they are connected to. This is why a functioning auditory nerve is essential for the success of a cochlear implant. After this, it is the same as natural hearing where the nervous system transports the signals to the brain for interpretation and a sense of sound is created.
Cochlear implants pack sophisticated technology into a small size. Based on the cause of deafness, the right tuning and relevant implants are needed to be inserted into the ear. In addition, the number of electrodes that are to be put into the ear is also dependant on the extent of deafness. Severe and profound deafness needs about 24 electrodes in the cochlea to recreate a sense of natural hearing. On the other hand, mixed and conductive deafness can be treated with around 10-14 electrodes.
It is a known fact that foreign objects do not always coordinate with the body. Cochlear implants are known to pose a risk of meningitis and it is therefore advisable to be vaccinated against the same prior to obtaining an implant. In addition, these implants are very delicate and sensitive and maintenance is needed. Information regarding these aspects can be obtained at the time of purchase and the brand that manufactures the implant will have services pertaining to the same.