Cochlear implants (CIs) are complex electronic devices surgically implanted under the skin behind the ear. These devices use electrodes placed in the inner ear (the cochlea) to stimulate the auditory nerve of individuals who have significant permanent hearing loss.
Not all types of hearing loss can be addressed by cochlear implants, and benefits vary greatly among individuals. Because users must learn to interpret CI sound, it can be difficult to predict how effectively an individual’s brain will be able to decipher the implant’s new auditory signals.
How do cochlear implants work?
Cochlear implants are not high-tech hearing aids. Hearing aids amplify sound for those who still have some residual hearing (for example, damaged hair cells in the cochlea). Cochlear implants bypass the damaged area by providing direct electrical stimulation to the auditory nerve.
A CI has a sound processor, signal coupler, internal receiver and electrode array(s).
How Does a CI Produce Sound?
- The sound processor captures sound and converts it into digital code.
- The digitally coded sound goes through the coil to the implant.
- The implant converts the digitally coded sound to electrical impulses and sends them along the electrode array, which is positioned in the cochlea.
- The implant’s electrodes stimulate the auditory nerve, which then sends the impulses to the brain where they are interpreted as sound.
Cochlear implants will not restore hearing to “normal.” Audiologists and otolaryngologists advise patients that hearing with an implant is not the same as biological hearing. Some CI users can pick up on environmental sounds only, while others regain enough hearing to use a telephone or listen to music. CI recipients and the people they interact with should be aware that cochlear implants do not enable a deaf person to function as a hearing person. Consequently, some CI users may still require accommodations like interpreters or real-time captioning.
Accommodation for CI Users:
CIs can be implanted as early as infancy or as late as adulthood. Users may have one implant or two. In addition to the many variations in CI function listed above, users themselves vary with a broad range of listening, speech, speechreading, sign language, literacy, and cognitive abilities.
This variety means that there is no single formula that works for everyone. Room acoustics play a major role in the intelligibility of speech for CI and hearing aid users. Other factors include:
- The strength of the signal
- Clarity of speech
- Distance from the speaker
- Competing noise
- Familiarity with vocabulary
- Whether the speaker is organized or rambling
- Number of speakers?
- How experienced the individual is with the CI
- Whether individual was exposed to spoken language before or after the hearing loss occurred
Some CI users prefer to use sign language interpreters; others prefer real-time captioning. The service coordinator can check with the individual to find out what kinds of communication environments s/he is comfortable with, and which are problematic. After CI users have some experience in the particular classroom or work setting, it’s a good idea to invite them back for further discussion. Some students are skilled advocating for themselves; others may need additional support, especially in a secondary or postsecondary environment.
Tips for working with CI users
- Face the person when talking
- Speak clearly
- If a repeated sentence is still not understood, try alternative phrases
- Provide preferential seating if requested
- Monitor environmental noise and light
- Point out who is talking
- Repeat questions/comments when leading group discussion
- Familiarize yourself with assistive listening devices
- Find out what kinds of communication environments work best for the student
- Speak while you are writing on a board
- Turn away from the person’s view when speaking
- Shout or exaggerate your speech
- Assume a CI user doesn’t use sign language or doesn’t want an interpreter
- Attempt to talk over loud environmental noise; wait for the noise to stop or move to a quieter location
- Speak with objects in front of your mouth.
- Pace around the room while speaking
- Assume anyone is aware of all available support services; make referrals if possible