So you now have your new cochlear implant. After waiting a few weeks for the surgery site to heal, you have your first ‘mapping’ session, the process of the implant being made active and adjusted for you. We have all seen or read about the experience of a child, for example, hearing for the first time. The impression given is that the new implantee now hears everything and recognises the sounds coming through. This is completely WRONG. This impression is very misleading and often gives rise to unrealistic expectations by both the implantee and more importantly, their family and friends.
I can tell you how it has been for me and I suspect, the majority of cochlear implantees. The audiologists who work with you in this process do every thing possible to explain how it is likely to work. Getting used to and adapting to a cochlear implant is very much an experiential thing - no hearing person is going to be able to adequately explain what actually happens. Every individual is different of course and the level of progress you make will vary.
I have been going deaf since I was a baby and thanks to much hard work, over decades, I have developed a significant level of skill that has enabled me to communicate effectively in the hearing world. Naturally, I assumed that I would do very well with my new implant - which I have - but only after months of ongoing work and effort on my part.
The first impression I had of the impulses being transmitted to my brain was of noise, just that, with no clue of what I was hearing. For a start, your brain is subjected to what is really a bombardment of sound, none of which makes any sense. Your head is now filled with ‘noise’ and it can take a huge toll on you, mentally and emotionally. For me, it was about 2 months before my brain began to convert all this new sound into meaningful words and even then it was very patchy. I was advised that it usually takes about twelve months for full integration and that was indeed my experience. In essence, the brain has to learn a whole lot of new things and this can be very disorienting.
The implant contains 22 electrodes which transmit sounds in the high, mid and low frequencies. Compare this with the normal number of hair cells in each ear (cochlear), anywhere from 17,500 to 23,500. So an implant is simply not capable of transmitting the full range of sound frequencies that a normal hearing person can receive.
In my case, the high frequencies had been missing for a very long time and I imagine my brain had even forgotten what these sounds were like, let alone know what I was now hearing. It is interesting to me that the very first sound I was able to clearly identify, was the ticking of a clock. Now it seems that I cannot avoid hearing ANY ticking clock!
I am enormously grateful for my cochlear implants. I was recently fitted with a second one, just on two years after my first, so am going through the same adaptive process. This time around my brain seems to have the ability to recognise the new sounds very quickly, which is a huge bonus. It will still take 12 months for full integration. Like all implantees, it is a gradual process of adjusting the sound thresholds and bit by bit, turning up the sound levels in the speech processor. This is something that cannot be rushed, as the auditory nerve has to gradually get used to the new stimulation. Otherwise it can be too uncomfortable if too much is done too soon.
Even with the implants it still takes a lot of mental effort and concentration to be able to function in the hearing world and that will always be the case. The cochlear implants help, but they cannot replace our natural hearing.