Re: Implicit human echolocation

[Thomas G Brennan <g_brennantg@xxxxxxxxxxxxxxx>]

I did o&m training to be a trainer but never bothered to pay the certification
etc.  That gave me a much better handle than just having had o&m training myself
as to the kinds of things you must consider.  It seems the ideal would be for
someone with o&m training, a blind person, and a psychoacoustics expert to work
together to design such experiments and run them on blind people, preferably
congenitally blinded people.  Of course, any time you're doing environmental
testing you have the problem of uncontrolable variables but that's a bit of what
the real world is all about when we echo locate.

I've also done some work with hearing aid clients and echo location and have
found some frequency issues and that, in general, once you get above a moderate
loss you're not likely to be able to do anything useful with echo location no
matter how good the training.  For truly good passive location you really pretty
much need to have no hearing loss.

My wife just had her eyes removed on Valentine's Day this year.  That has really
made me wonder about research concerning echo location in such cases and its
changes.  Obviously there is an extremely small population to work with.
Spacial issues would also be interesting to investigate.  She and I both found
major alterations in our spacial worlds after surgery and mine has never gone
back to what it was.  Dee's is too new but other blind folks I've talked to who
have had some form of removal of the eyes (filling with oil is a different
issue) have had varying degrees of spacial alteration and all who use it have
reported to me changes in echo location mapping and how they use the information
they obtain.

Tom


Tom Brennan  KD5VIJ, CCC-A/SLP
web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html