The EP of This American Life is that basically with a little practice most blind people can learn to see with echolocation. Yes I know it sounds incredible but listen to the episode. The TL;DL version would be
(1) blind people can learn to echolocate
(2) MRI scans prove they are actually seeing, no colors but shapes
(3) People that could see but then went blind and learned to echolocate confirm they can see.
(4) The fact that most people think blind people can't do anything and need and then offer so much help prevents most blind people from learning to echolocate and start seeing.
don't shoot the messenger.
http://www.thisamericanlife.org/radio-archives/episode/544/b...