Blind people echolocate with visual part of brain

When a blind echolocation expert (left) hears the clicks and echoes of his echolocation, his brain lights up in the fMRI scan. The brain of a seeing man who does not echolocate (right) does not light up. University of Western Ontario
Blind people who navigate using clicks and echoes, like bats and dolphins do, recruit the part of the brain used by sighted people to see, a new study has found.
While few blind people use echolocation — emitting a sound and then listening for the echo to get information about objects in the surroundings — some that do are so good at it that they can use the ability to hike, mountain bike and play basketball, said Melvyn Goodale, one of the co-authors of the study published Wednesday in PloS One.

Goodale, a psychology professor and the director of the Centre for Brain and Mind at the University of Western Ontario in London, Ont., said he was amazed by the abilities of the two blind men in the study.
"They can tell a flat thing from convex. They can tell a bush from a wall, a car from a lamp post," he said. One of the two subjects, Daniel Kish, 43, could localize objects to within three degrees — "incredibly accurate," Goodale said.
Both Kish and a 27-year-old male subject trained by Kish could also tell which way objects were moving. Goodale and his research team wanted to find out what was happening in the brain while people like Kish were echolocating...

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Emily Chung @'CBC News'