Music makes my heart sing

19 06 2010

I’ve just had my 3 month checkup. The first person I saw was my surgeon who is a very happy bunny. All looks good! My internal implant is a little sore along the side of the bump, this turned out to be where it touches the processor. I’ll need to hop along to my opticians and get the arm of my glasses (and sunnies!) adjusted so it doesn’t press against the area behind my ear and weaken the skin.

I then went to see my audiologist. She was also very happy at my progress. I had all my electrodes set again to maximum comfort levels and was given a slight increase in sound. I asked for ClearVoice (high) to be replaced with a normal program with a wider IDR (Input Dynamic Range) of 70 for music. With a wider IDR (explained here), you gain a wider range of sound. For the last two weeks, music has sounded pretty much perfect. When I listen to my iPod with the 70 IDR, it sounds even better, it’s so beautiful that I don’t want to stop listening. If I close my eyes, I can pretend I am hearing in stereo, as I sit enveloped in this wonderful sound that is in-my-face-listen-to-me, full and rich, swirling around my head and making me feeeeel the emotion. Vocals sound normal and some are so beautiful that they make me want to cry. Isn’t this what music’s all about?

I had a hearing test and have improved in the last 2 months so this was great news. The decibel range of zero going down  to -30db is considered to be a normal range of hearing for a hearing person (above the red line).

Red dots : My hearing 3 months after activation
Blue dots : My hearing 2 weeks after activation
Black dots : My hearing before the cochlear implant

My speech and language therapist tested me on my language comprehension, in the left ear with cochlear implant only. Here’s an updated progress chart from pre-implant through 2 weeks post-implant, to my current 3 month status. I’m aiming to get all speech comprehension scores close to 100%.

KEY:
Sentences in quiet = Listening to sentences without lipreading
Words in quiet = Listening to single words without lipreading
Lipreading & sound = Lipreading and listening to a speaker’s sentences
Lipreading in quiet = Lipreading a speaker’s sentences with no sound

The biggest change has been my ability to hear sentences in a soundproof booth, it has jumped from 24% with a hearing aid to 43% with a cochlear implant. If I did not have the cochlear implant, this ability would have continued to decline. I have been able to understand some words when listening to my Harry Potter audio book, it’s so exciting when I am able to pick out a bit here and there. It’s hard work, it’s almost like concentrating but trying not to concentrate too hard – like when you look at those magic eye 3D pictures and try to see what’s hidden there. My ability to hear words in quiet hasn’t changed, as this is very difficult to do without context to help.

My lipreading in quiet scores, at 43%, are very high. I spoke to a professor whose area of interest is forensic lipreading, and she said most people would score 5% in lipreading in quiet. Deaf people get to practise lipreading every day of their lives but as there are so many homophenes and unseen phonemes, it is not possible to score 100%. It’s great that I can still lip read well – and thank goodness I can, or I’d be stuffed trying to get through all of this! I’ve been worried that my ability to lipread would decrease as I learn to hear and try to break the habit, but my audie reassures me and academic studies show this is not usually the case. However, some of my implanted friends say they cannot lipread any more, discovered when they run out of battery power and are forced to rely on lipreading. So I don’t really know if I’ll be able to hang onto my lipreading ability.

I have experienced some new sounds in the last month. The beeping as the green man (walk/don’t walk) sign flashes when I cross the road, and I can hear it All The Way Across The Road. Amazing! I went to see a ballet, Swan Lake, at the Royal Albert Hall.  This was my first visit to a ballet. I was able to hear the orchestra very well and was surprised to see the ballet dancers enter and exit stage very beautifully and gracefully, but with an incongruously ungraceful THD THUD THUD THUD THUD THUD at the same time! I peeled a banana this morning and was surprised by the loud SSSSSSSSSSS sound it made. I then popped out to the shops and another new sound had me jumping in fright so much so that I almost threw myself into the nearest wall. I heard this very loud and deep roar right behind me, I could almost feel it and it jumped out of nowhere, I didn’t know what it was, and it frightened the crap out of me. I used to be scared of dogs that jumped and barked at me so maybe this is where that fright came from, apart from it being so loud and unexpected. I then saw a Harley Davidson go past, obviously it revved just before it reached me. SHEESH!

Although singing voices sound normal, speaking voices don’t sound normal yet (when people talk to me directly) although they are not far off.  I feel as if I am living on Planet Cartoon as people walking past still sound like Minnie Mouse or Donald Duck.

And my shoes squeak all the time! Bah!





Cochlear implant mapping

4 05 2010

I’ve had 5 “mapping” sessions since activation. A mapping is a reprogramming of the cochlear implant, to readjust the electrical stimulation limits of the electrodes as each user’s brain adapts to sound and fibrous tissue grows over the internal implant. Mappings are typically carried out once a week for the first 6 weeks, then every few months, then twice annually.

At each mapping I was given increased volume and it was an opportunity to address any concerns with the audiologist. This was followed by a coffee break in the hospital cafe then a speech therapy session. I have one more mapping session this week, then my next one is in June when I have my 3 month check.

It’s been a rollercoaster ride. I’ve started with beeps and pushed so hard that I got a constant whine when I put the implant on. This set me back and I had to slowly build up my tolerance again of high frequency sounds from zero, bit by bit, and have successfully avoided a reocurrence of the whine. I have not yet reached full volume, there is still some way to go, which is kind of scary. I found last week quite difficult as everything seemed too loud and I started feeling stressed, but I hung in there and carried on wearing the cochlear implant until I got used to the increased sound levels.

Increased sound levels can be problematic for cochlear implant users because they are more sensitive to loudness changes. A normal hearing person can hear a wide range of sounds from very soft whispers to loud rock bands; this dynamic range of hearing is about 120dB (normal speech is within the 40-60dB range). However, a cochlear implant processor’s input dynamic range (IDR) or sound window is limited to an electrical current of 20dB, and 120dB of sound needs to be compressed into this. Therefore the cochlear implant user is more sensitive to changes in loudness than a hearing person.

If the IDR is small, sounds outside the IDR need to be omitted or compressed; sounds that are too quiet will be cut off, and sounds that are too loud will be compressed and will sound distorted. The 3 main brands of cochlear implants have different IDRs; Advanced Bionics has 80dB, MedEl 55dB, and Cochlear 45dB but with autoranging. I currently have my IDR set at 60dB.

What actually happens in a mapping session? I replace my processor’s battery with a direct connect input lead to the audie’s computer and put the processor back on my head. (Yeah, this freaked ME out the first time I did this).

The audie’s software will reprogramme my implant’s Harmony external processor.

My cochlear implant has 16 electrodes and when each one is stimulated, I will sense each stimulation as a beep.
The audie will set the Threshold (T) levels [to access soft speech and environmental sounds] and Comfort (M) levels [the amount of electrical current required to perceive a loud signal] for each electrode by judging the most comfortable and the highest stimulation I can tolerate – the most comfortable and loudest beeps I am happy to listen to.

I use the loudness scaling chart to indicate to the audiologist which level each stimulation correlates to, ranging from ‘Just Audible’ to ‘Too Loud’.

Then the audie ensures the M levels are similar in terms of my perception, so that the volume is the same in each electrode – I was able to tolerate very high levels of high frequency sounds this week but she brought these back down, otherwise everything would have sounded weird and unbalanced.

This mapping method is rather tedious and drawn out over several months. Clarujust is new software (currently in FDA trial) from Audigence Inc where the patient and processor are interfaced to a computer and words are played and repeated as heard, the software adjusting the map accordingly. Mapping this way reportedly takes 30 minutes. This software can be used by all hearing aid and cochlear implant companies except Advanced Bionics, however Phonak signed up with Audigence Inc this year prior to the Advanced Bionics/Sonova acquisition.

When a mapping is new, it tends to sound louder, until I get used to it. It takes 3 days to get used to a new mapping, then I find loud sounds have become softer and more tolerable, and I can hear a wider range of soft sounds. It is uncomfortable turning up the volume of life to the max every few days. I still have to brace myself for the jolt first thing in the morning, making the transition from complete silence to a full technicolour river of loud sounds pouring into my brain. Amanda’s Tip of the Day: If you wake with a hangover, take your time to put on your CI and turn down the volume. It helps. A little.

It’s an amazing learning process as I am also trying to identify sounds as well, discovering amazing new ones, and learning to discriminate between things that sound similar to me. My hearing is like a baby, it needs time to learn and grow, but it can be fun too.

Erber’s model set forth 4 levels of auditory skill development;

    Awareness of sound (presence v absence)
    Discrimination (same v different)
    Recognition (associating sound/word with meaning)
    Comprehension (using listening for understanding)

I have now reached the second level, I am hearing things but finding it difficult to discriminate between some sounds. Obviously, this means I am still lipreading. In my speech therapy session this week, I discovered I can’t distinguish between Gear v. Dear, tIme v. tAme. I can listen and fill in a word missing in a written sentence, but listening to a whole sentence and being given one written word is more difficult. With hearing aids, both tasks would have been impossible.

In addition to mapping, my progress is occasionally evaluated with an audiogram and speech perception performance with the cochlear implant in a soundproof booth. These tests assist the mapping process and indicate any further adjustments required. I expect I’ll have this done this week, and hope to have improved upon the 18% I achieved in my last speech perception test.

I was programmed with ClearVoice last week but am still adjusting to my new mapping, so I have just been ‘tasting’ this wonderful addition. I tried it on the train; the roar of the train engine and clashing sounds (brakes or pressure pads? – haven’t worked this sound out yet) dropped away significantly and I could clearly hear voices around me. It was awesome. Yesterday, I was sitting by a window and became conscious of this sound. I realised it was the rain spitting outside. In the garage, I could hear the drumming of the rain on the roof and the traffic outside. With ClearVoice on, the traffic became very quiet and the rain became a very clear high PLINK PLINK PLINK, and a lower PLONK PLONK when it came through a hole in the roof and landed on an object. Again, awesome!

Try out the ClearVoice demo for yourself. Don’t forget to say the mandatory WOW!

Shanti is waiting for her cochlear implant operation date and works as a personal trainer and complementary therapist. She gave me a super aromatherapy massage yesterday and I left feeling very relaxed. As soon as I left, I plugged into my iPod and was amazed to hear that the tinny / Donald Duck tone of vocals had gone from a lot of songs. Perhaps there is a link between relaxation and better hearing. Today, voices sound largely normal and it’s so so so NICE to have some normality again!

Photos courtesy of Byron