My 4 year old son has been diagnosed with severe sensorineural hearing loss in both ears. He was not born this way; we believe he lost his hearing sometime between 2.5 and now. He was just diagnosed in June and he will be getting his first pair of hearing aids at the end of July. I’ve been told by his ENT and Audiologist that we need to make a decision about cochlear implants (CIs) very soon. My son had lots of vocabulary and speech sounds; he now is a little difficult to understand but communicates with family and friends. My question is where can I find good information about CIs and also why must I rush to make a decision?
It sounds as if your child’s loss predominantly occurred after he acquired verbal speech and auditory language, so his deafness is categorized as “post-lingual.” This means your son’s brain has a memory of what speech sounds like, even if that memory and how to reproduce it are fading a bit. That is one reason why implantation is recommended sooner rather than later – research has demonstrated that the shorter the lag between onset of the hearing loss and input from a cochlear implant, the better the child does. We believe that is because the auditory memory (part of that auditory path design) has had less time to “forget” the sounds of speech. There are lots of research articles that talk about keeping that time-frame short between onset of hearing loss and use of the CI, although outcomes are more variable than they might appear.
The signal from the hearing aid is amplified speech and other sounds, so your son will hear things at a louder level with his aids. The sounds will be distorted and some sounds may not be transmitted very well (sounds like /sssss/ and /shhhhhh/). His brain and his ears are connected by a path of nerves (the auditory path), and the signals that the ears receive must be interpreted by the brain. There is big difference between the signal provided by a hearing aid (loud speech) and the signal transmitted by the cochlear implant (kind of like Stephen Hawking’s electronic speech).
Without knowing more details as to the cause of the hearing loss, it is unclear whether there are specific reasons for recommending earlier implantation – some audiologists and ENTs simply believe that CIs are for almost every deaf children and the sooner the better. However, I can tell you that there are some conditions that can cause a bony growth to happen in the cochlea (which is the organ if hearing) and, if so, this growth begins after the hearing loss in a gradual and slow manner. If this occurs, the longer one waits, the more difficult it can be to insert the electrode of the cochlear implant.
There may be other reasons your healthcare providers are wanting you to make a decision, but you need to do your homework first. One of the predictors of children’s success with CIs, literally, is how much time their parents spend getting information on the subject. Here are two links that let you compare what the signals of a hearing aid sound like and the signals of a Cochlear Implant sound like
Here are some article review links:
[Ed. – For more, very objective information visit the UK's Ear Foundation]