I teach the Cochlear Implants class at my university and so have occasion to stay "up" on this; 8 channels is still what typical CI users are getting. Basically a CI is a string of electrodes floating in a electrolyte solution, and so the current spread is significant no matter the number or spacing of the electrodes or even how close to the modiolus the array is placed.
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Sarah Hargus Ferguson, Ph.D., CCC-A
Assistant Professor
Department of Communication Sciences and Disorders
University of Utah
-----Original Message-----
From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxxxxxxxxx] On Behalf Of Bob Masta
Sent: Tuesday, October 15, 2013 6:11 AM
To: AUDITORY@xxxxxxxxxxxxxxx
Subject: Re: How to speak to people about hearing loss and more
On 14 Oct 2013 at 15:04, Kevin Austin wrote:
The new [sic] generation is in the middle of this "plague of silence".
Implants?
what do they sound like?
http://www.youtube.com/watch?v=SpKKYBkJ9Hw
http://www.youtube.com/watch?v=00WOao4kpwM
There may be examples of 128 and 256 channel reconstruction somewhere
out there. Consider that 256 channels only yields about 1/3 semitone
bandwidth, probably ok for speech and autotuned music.
http://www.youtube.com/watch?v=OvHmrShrmaM
My understanding (which may be a few years out of date) is
that cochlear implants rarely get more than 8 or so useful
channels in actual patients, no matter how many channels
there are on the prosthesis itself. Partly this has to do
with insertion and positioning issues, but mostly it's due
to the fact that the closer the electrodes are spaced, the
closer they have to be to their targets in order to be
separately resolved... and you just can't get all that
close.
Best regards,
Bob Masta
D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Signal Generator
Science with your sound card!