Whew! I was right in the middle of the process of writing a new post when it hit me: I woke up Sunday morning, and had severe vertigo and nausea. I had trouble getting to the bathroom, and when I got there I was so sick I had to puke. It took a few hours before I realized that it could be connected to the implant, and that it would be a smart move to call the hospital. Once thought, action was made. They wanted me to come in for a checkup, and when I got there, I was immediately admitted for observation and tests.
Two days later I was released and relieved. I was much better. They found no infection, and the most probable diagnosis to my illness was “benign paroxysmal positional vertigo” (BPPV) which can affect anyone. I recently had a new mapping, and up until the attack of this BPPV I felt as if the sound had gotten worse (after an initial wow-sensation and a feeling of it being much better).
These following thoughts of mine are merely theories and are in no way substantiated by any data or real tangible facts: there is a possibility that there was a minor leak from where the implant enters the cochlea, and that the sudden drop in the pressure inside the cochlea/vestibular/canal labyrinth caused the symptoms I experienced. I have very much the same balance/vertigo feeling as I had in the weeks after the implantation. It’s not very bad, but it’s ever present, and it is only felt when I actually move my head. I sleep more, and have more troubles fixating my eyes to text or smaller objects. I do exercises every day.
OK, enough about that, now over to what was meant to be my original post:
Date of writing: 18.11.09
Got a new mapping yesterday, and that was an interesting experience, both during and especially after. Evidently AB has upgraded both the console software as well as the CI-software. Yeay, I have been software upgraded for the first time in my life!
They had added enhanced ability to control the width of the sound waves produced by the Harmony processor. The software has two automatic settings, and as an extra feature, the possibility to manually manipulate these values. In short it is about how much energy that the sound waves deliver. The amount of energy is calculated by a simple (very simplified) formula: “Total amount of Energy” = “Sound wave width” x “Sound wave height”. This is sound physics ABC.
The shorter the wave width, the more waves per second is possible to expose the cochlea nerves to. That is a good thing, it means more information, and perhaps closer to mimicking mother nature? The downside of more narrow waves, is that the height has to increase similarly. If not increased height, the total amount of energy delivered is less, and it will be perceived as lower in sound strength (ie. lower volume). In order to compensate for that perceived low sound, one has to increase either the width or the height. If the height is increased too much, the sound may sound distorted or otherwise imperfect (I don’t have real data on this effect), and also the impedance will get too high, meaning that the battery will have to deliver more power to push trough the sound, thus making each recharge lasting for shorter time…
Anyway, we use one of the automatic settings, and went with the wave width that the software recommended based upon the historical data about my CI-development. Aside from that techie nerd stuff, we lowered the high-pitch sounds, increased the bass and middle area. I have no problems hearing the high pitch sounds, and I understand what they are, mostly. What I have trouble with is voices, sounding high-pitchy still, and bass-sounds in music. Program 1 is based on maximum level on all frequencies, program 2 lowered high pitch and program 3 is same as 1 without AGC (yes trying to figure out the impact of AGC again… [Edit: Had to trade program 3 back to the old program 1 after the incident in order to rule out the possibility of some weirdo implant-induced disturbance to the balance. Not so.]
On the way home, in my car, with the music blaring helped by my subwoofer, I listened to my “control”-music, and could actually pick up a few bass-guitar sequences for the first time! That was good 🙂 I have been missing that aspect of the music. Voices sound better, music sound better, and irritating sounds (mostly from high pitch sources) have subsided a little bit. We did a little test to see if I could distinguish between two words that was impossible for me to distinguish prior to this mapping: (they are Norwegian, meaning “nun” and “many”, the important thing to have in mind here, is that both words have two syllables, and they are very similar in pronunciation, despite their very different meaning) nonne [‘nɔnə] and mange [‘mɑŋə]. I caught the right words many times enough to say that this mapping fixed the problems for me distinguishing between [n] and [ŋ]. Also the difference between wovels like ɔ and ɑ, has been really hard to pick up. Don’t know yet how of if that has improved. (have a newly throat operated 4 year old, so haven’t had the luxury of training properly the last week…)
I’m now leaving the post-CI-calendar and go back to the regular calendar, too much to keep track of, better to simplify things 🙂