The Borg are coming!

Life as a bilateral cochlear implant recipient. If the topic is new to you, check out this background information on cochlear implants; while the article is somewhat dated (1998), it does cover a fair amount of history.

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Location: San Francisco, California, United States

My opinions are my own, unless they would get me into trouble; in that case I don't know whose they are.

Sunday, October 27, 2002

A couple days of observations of new settings

[Warning: heavy technical jargon follows. For more information about the various programs and settings, check out Cochlear Corporation's website]


Body Pack:


1) 900 Hz with low emphasis and ADRO
2) 1800 Hz with low emphasis and ADRO
3) 900 Hz with neutral emphasis and ADRO
4) 1800 Hz with neutral emphasis and ADRO

[Adaptive Dynamic Range Optimization (ADRO) is a pre-processing algorithm designed to improve access to low-level sounds to increase the salience of the softer phonemes of speech, while keeping louder sounds comfortable. ADRO is only available with the SPrint (body worn) processor.]

BTE:


1) 900 Hz with low emphasis
2) 1800 Hz with low emphasis

Low frequency emphasis works great :


I used the body pack all day Friday (office) and most of Saturday (morning doctor's appointment, afternoon at a picnic). I experimented with programs 2 (1800 Hz with low frequency emphasis) and 4 (1800 Hz neutral). In all situations, both programs resulted in similar speech comprehension, though in outdoor settings and with program 2 I had to concentrate more to pick up voices over the environmental sounds.

The real benefit for speech comprehension from low frequency emphasis surfaced while listening the computer CD player and using the AV patch cord with sensitivity set to 0 (I have the book and CD set of the Night Listener by Armistead Maupin):
• I tracked easily
• I could start the CD at an arbitrary point in a chapter and find the location in the book
• I could take my eyes off the page and get the gist of what was being read to me, sometimes to the extent of understanding full paragraphs
• With the neutral setting I could only track, and even then sometimes lost my place.

Low frequency emphasis and the joy of music:


For listening to music -- with and without singing -- I love the low frequency emphasis. This morning I listened (and sang) along to my favorite songs from Les Miserables. With one in particular, the mix of voices and music was so beautiful, I cried. Without the low emphasis, I'm able to better separate the lyrics from the music, but everything sounds tinny, and the the voices mask the music, making the listening experience incomplete.

900 Hz is enough (compared to 1800 Hz):


I've come to the conclusion that 1800 Hz does not offer better information than 900, either for speech comprehension or music. I did notice that at 1800 Hz:
overall sounds are shifted toward higher pitches; this is not a desired effect.
less volume; e.g., 1800 Hz at volume 9 is roughly equivalent to 900 Hz at volume 6.

Discomfort with 900 Hz programs on the body pack:


I started out with volume 7 on all programs on the body pack. I quickly shifted to volume 9 on all 4 programs, and that turned out to be a mistake. I related in a subsequent email that pain started in the back of my head; it only surfaced with the 900 Hz programs and spiked with certain sounds like "sh."

I realize now I was trying to get the sound input with the 1800 Hz that I was receiving with the 900 Hz. I had erroneously assumed that I was building up tolerance and I would want the same volume across the board. With the 1800 Hz rates, my brain can handle the extra volume - and likes it! On the 900 Hz programs I'm now keeping the volume between 5 and 7; the discomfort is still present but tolerable.

The puzzling thing is that on the BTE I don't have any pain with the 900 Hz program, and in fact can tolerate loud volume without discomfort. In fact, using the computer CD player and AV patch cord jacked into external speakers, everything set to maximum was comfortably loud. The only sounds that are annoying with the BTE are the crinkling of paper.

With the body pack, focusing on low frequency emphasis programs:


I'm staying mostly on the low frequency emphasis programs to see how well I do with it in noisy surroundings. So far, while voices are not as easily distinguishable from ambient noise as without the low frequency emphasis, I still appear to be understanding people well, especially when I reduce sensitivity. The biggest problem is being out in the street; god, do environmental noises sound loud! Next week at the office, I will explore more how much low frequency emphasis provides better speech discrimination in noisy environments.

With the BTE, focusing on program 1:


Thus the rest of Saturday and Sunday I went around with the BTE using the low frequency emphasis program at 900 Hz, especially since it conserve battery compared to the 1800 Hz. I would like to try something else in the other slot, perhaps a program without low frequency emphasis?

Thursday, October 24, 2002

One month adjustment: introduction of low frequency emphasis and using ADRO

After the mappings, I was tested on speech comprehension and I'm up to 30%, as compared with 18% with the hearing aid. Granted that these are simple sentences in a controlled setting, but it's a great sign of how much more I'm understanding speech.

I've now switched to the body pack and will be testing out the various settings for the next few days. A few observations I wanted to note for future reference:

• I'm using volume 7 for all 4 programs. It's great to have such high sound input with no facial twitching.
• Music sounds wonderful now!!!
• With either low emphasis setting, whistling high notes sound strange; they sound very breathy and too much of the high pitch is lost. • On the other hand, music sounds richer and more full with the low emphasis settings.
• With either low emphasis setting, the computer fan is once again noticeable and somewhat distracting. I assume I will get used to it with time.

I haven't had a chance yet to experiment with listening to books on CD, and I will do so in the next few days.