Having been assessed as deaf enough for a cochlear implant, and passing the associated tests, I was wondering how much of an improvement in hearing the implant has given me. Lots of new high frequency sounds have been popping up whilst low frequency sounds have only just started coming back. It has been exactly two weeks since my cochlear implant has been activated and my world has certainly changed in that short time.
I went for another mapping session to increase the volume and tweak the settings. I can hear music fairly well, rock and piano music sound scratchy with the singer sounding as if he has laryngitis. Not a good sound. However, I discovered that opera sounds good and there is plenty of that on YouTube. I am able to follow a melody and detect when there are words, but not understand them. Japanese music also sounds passable at the moment. I spent a long time on iTunes trying out different styles of music to discover what was pleasant to listen to, as I believe in the power of music to help achieve great things. I have purchased Ravel’s Bolero, Grooploop – Piano (Japanese Animation: Studio Ghibli Soundtrack), John Kaizan Neptune & Také Daké : Asian Roots.
Remember my activation video, two weeks ago, when I couldn’t hear the bells? I can hear those bells now, no problem! I can hear the blackbirds in the trees outside my house. I am now hearing the trains and traffic that have been missing for the past two weeks, as my brain focused on the new high frequency sounds. The tinnitus has largely disappeared in my bionic ear but is still present in my unaided ear (mostly mad musical performances).
Today, I had a hearing test, and I’m jumping bananas. Speech bananas, that is. Whoop!
A speech banana is the shape on the audiogram of all the sounds of speech or phonemes of all the world’s languages. I have never been able to hear most of the speech sounds within the banana, even with hearing aids, so I relied on lipreading and became very good at this.
My new audiogram had my jaw hitting the floor in shock. For once, I was speechless.
Blue circles : my left ear as it was up until two weeks ago.
Green circles : bilateral hearing with hearing aids (Note: bilateral scores higher than unilateral)
Red circles : left ear with cochlear implant.
NR : No Response
I have yet to be tested wearing a cochlear implant plus hearing aid together, which will increase my speech comprehension scores.
CUNY test (lipreading with sound) > Nov 2009 : 91%
CUNY test (lipreading with sound) > Apr 2010 : 85%
BKB test (listening only) > Nov 2009 : 24%
BKB test (listening only) > Apr 2010 : 18%
As everyone still sounds like Donald Duck, I was not expecting to do very well in my speech perception tests. With daily practice at listening, these figures will improve. I also have yet to receive a lot more increase in sound stimulation, I’m about half way to my target in this respect. So …. *shrugs*
So why am I showing good results in the hearing test, yet a poor performance in speech perception? And how do these results translate to the real world? A hearing test is always carried out in a soundproof room. A hearing test is performed using pure tones, but speech is made up of complex sounds. Add background sounds in the real world, and speech perception becomes even more difficult. Add the cocktail party effect, and it’s not easy to manage in noisy environments with a hearing loss, as you then lose the ability to discern speech in noise. Such measurements however do offer audiologists a way of measuring progress. I now have a baseline to start from (BKB 18%, CUNY 85%) and can monitor my progress against my new figures. Later on, I also expect to be tested in noise. In the real world, Advanced Bionic’s new ClearVoice software is going to help me with the cocktail party effect, and I expect to get this next month.
Donald Duck aside, it is going to take some time for my brain to decode the new stimulation, especially in the high frequencies where I had no sensation before. An analogy would be (re)learning the roman alphabet, only to have written French instead of English on the page. According to my audiologist, the best strategy to manage this is to practice daily listening to an audio book and follow the unabridged text at the same time. I have collated several links for such rehabilitation work on my cochlear implant rehabilitation page. My audie says, the more work I do, the more new pathways my brain will create, and the better my brain will become at deciphering the strange new sounds. For someone who was born deaf, like me, this process can take up to two years. I need to remember three key things – patience, persistence and practice. It really has helped to have a mentor throughout the whole process to ask questions of, to give you encouragement at every stage of your cochlear implant journey. You can find a UK mentor here and a US mentor here.
My world is opening up and all the colour is flooding in – at last!
(I still can’t get over that darn audiogram!)