Re: Fwd: AUDITORY On cochlear implants (CI) and hearing

Subject: Re: Fwd: AUDITORY On cochlear implants (CI) and hearing
From: David Hirst (
Date: Wed Mar 09 2005 - 17:16:22 EST

An ex-honours student of mine, Thomas Stainsby, went on to do his PhD at
the Bionic Ear Institute here in Melbourne and his project was specifically
how to extend their models, which had been developed to assist with speech
recognition, into the realm of music perception.

For those who want to follow up this issue further, Thomas is now in the
Dept of Experimental Psychology at Cambridge University in the UK. His PhD
thesis is entitled "The perception of musical sounds with cochlear
implants" and is available at the University of Melbourne Ballieu Library.



At 12:10 AM 10/03/2005, you wrote:
>Some background:
>>>A cochlear implant is a small, complex electronic device that can help
>>>to provide a sense of sound to a person who is profoundly deaf or
>>>severely hard of hearing. The implant is surgically placed under the
>>>skin behind the ear.
>Date: Wed, 09 Mar 2005 00:01:27 -0500
>From: Automatic digest processor <LISTSERV@LISTS.MCGILL.CA>
>Date: Tue, 8 Mar 2005 12:20:13 -0500
>From: Ray Goldsworthy <raygold@SENS.COM>
>Subject: CI Music Perception
>Dear list,
>Hello, I am a new member. A colleague pointed out this list to me since
>I am a CI user as well as a research scientist interested in CI
>psychoacoustics. I thoroughly enjoy listening to and playing music. I
>play drums and keyboard. I lost my hearing suddenly to meningitis at 12
>and was implanted at 13. As a child, I did not have a good sense of
>harmony, nor could I sing in tune, but I began playing drums around the
>age of 11. I am now in an amateur band and listen to several hours of
>music every day. Preferences tend towards rhythmic pieces such as Indian
>music (I also play tablas) and bluegrass (love the finger-picking), but
>I my interests vary.
>The greatest deficit that I have noticed is that I don't feel a strong
>percept associated with chords. I do experience a weak percept allowing
>me to classify a strong harmonic diad such as tonic and fifth, or tonic
>and octave, versus tonic and major 7th. But in a controlled study, I
>think I would fail to classify majors versus minors.
>A couple comments related to previous threads. First, I think I know a
>CI user who can sing in tune. I've always felt that I was one of the
>stars of the implant world, but this guy is phenomenal and is more of a
>professional musician than me (i.e. he gets paid gigs). He is a
>keyboardist, but is trained so well, that I wouldn't be surprised if he
>can match his voice.
>Second, and this is huge. Please do not think that the CI simulations
>currently used are accurate is transmitting the percept of sound. At
>best, they are accurate indicators of the information content
>transmitted by a generic CI sound processing strategy. The moment you
>use either a noise carrier or sinusoids or even band-limited impulse
>trains, you are producing a percept that is fundamentally different from
>what music sounds like to me. As a musician dances upwards in a scale,
>the individual notes produce distinct electrode amplitude patterns that
>in turn produce a percept (hopefully pitch matched). But for a NH
>listening to a CI simulation, two adjacent bands being bombarded with
>band-limited noise carriers is not going to produce the same percept at
>all. To begin with, using noise carriers will introduce temporal
>fluctuations in the envelope signal that is distinctly interpreted as
>noise. I could go on, but I feel I am going to fast to make a cohesive
>statement, so will stop.
>I hope these comments prove interesting since they are my introduction
>to the list....
>Sensimetrics Corporation
> 48 Grove St.
> Somerville, MA 02144
> Tel: 617-625-0600 x240
> Fax: 617-625-6612
> email:
> web:

David Hirst
Senior Lecturer, Educational Design
Information and Education Services
University of Melbourne
Victoria, 3010
ph +61 3 8344 7568
Fax +61 3 8344 4341

This archive was generated by hypermail 2b27 : Sat Dec 22 2007 - 01:46:07 EST