May 30, 2011 
Blind people can become highly skilled in listening to the sounds of echo…
Some blind people become so skilled in listening to the sounds of echo, that they produced by clicking with their mouth, that they can literally use this ability to ride a mountain bike or play ball games.
It is known that bats find their way at night by using a biological version of sonar, called ECHOLOCATION. So far it was only suspected that the blind man can develop the same skill, but nobody has proved it.
However, Canadian scientists have proven that they can. It is interesting how a blind person can do this by using a part of the brain that is normally involved in processing visual information.
This discovery was achieved with the brain scan of two male volunteers who were both blind since childhood, aged 43 and 27, reports the Telegraph.
Both of them were asked to go out and try to distinguish different objects such as a car, the flag pole or a tree, all with clicking sounds that they produce with their mouth, and then by “capturing” the echo signal.
Small microphones were placed in the ears of volunteers to record the outgoing and incoming sounds.
Later, these sounds were reproduced to the volunteers, and at the same time their brain activity was monitored using magnetic resonance imaging (MRI).
During the playback, the volunteers were able to identify individual objects using only the echo.
MRI scanner showed that the echo is actually processed by a brain region that is typically used to process visual information.
Any activities associated with the echoes were not observed in the area of ??the brain responsible for hearing, for which one might expect to process sound.
43-year-old, who lost his sight in an earlier part of life, showed better results. His eyes were removed with only 13 months due to a rare form of cancer which is called retinoblastoma.
The same test conducted on people who are not blind did not demonstrate the ability of echolocation, and any activity connected with the echoes was not observed in the visual brain regions.
Lead researcher, Dr. Mel Goodale from the University of Western Ontario, concluded this awesome discovery: “It is now clear that echolocation allows blind people to do things that are normally thought to be impossible without the vision and that this way helps the blind and visually impaired to provide high degree of independence in their everyday life.”
Taken from: www.centar-zdravlja.net