Cochlear implants (also known as 'Bionic Ears') are devices that transform auditory acoustic information into an electrical signal delivered directly to the auditory nerve. They are mainly used to address profound bilateral hearing loss, particularly in adults that have become deaf and children born with congenital deafness, providing them with the possibility of oral communication.
Cochlear implants: how they work
The outer part :
Sound is received by a microphone and passed to a processor (1), which converts it to an electrical signal. Then, an antenna (2) transmits it across the skin to the internal part (3).
The internal part:
Surgically implanted, this part (3) captures and sends the electrical signal to an array of electrodes (4) that have been placed in the cochlea. This array delivers tiny electrical impulses which stimulate the auditory nerve.
The neural signal created is then sent to the brain where it is analysed and interpreted.
Responsibility and the decision to implant
The decision to implant, the intervention itself and the patient's follow-up is carried out by a multidisciplinary team, which is generally composed of ENT doctors, speech and language therapists, audiologists and psychologists. The characteristics of the hearing loss, age, the desire to communicate and using which methods, and other potential problems (such as autism, hyperactivity…) are all factors that are taken into account before deciding to implant.
Understanding speech with a cochlear implant requires both time and a fundamental re-education to integrate the received auditory information. This training occurs with help from speech and language therapists, audiologists, but also in the day-to-day by personal exercises (CD, internet, listening to environmental sounds...)
Cochlear implants: their limitations
Beyond the implantation criteria, cochlear implants also present perceptual limitations. Worldwide, comprehension in silence is achieved by a large majority of people that use an implant. However, having a conversation in a noisy environment or perceiving music are difficult sound situations. For example, listening to music generally leaves a divide in implant users: some will be able to appreciate music and may recognise some words or melodies; whilst others, on the other hand, will find this very difficult.