I heard an intresting program on the cbc today about a program that aloows people to see images with their ears. the link is here the sections about 20 minutes
http://www.cbc.ca/quirks/archives/04-05/apr02.html
It raises the issue that brain may not even have cortex specialized for visual or auditory information but that it just has pecial areas designed to to intrept information regardless of the sensory input it receives.