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Blind Man Navigates Obstacle Maze Unaided
iammani writes "The NYTimes runs a story about a blind man (blind because of a damaged visual cortex) successfully navigating an obstacle maze, unaided. Scientists have shown for the first time that it is possible for people who are blinded because of damage to the visual (striate) cortex can navigate by 'blindsight,' through which they can detect things in their vicinity without being aware of seeing them."
"Without a working visual cortex, nothing from the eyes enters the brain. At all."
Whoopsie. Apparently you didn't know about the body of work showing that there are connections between the retina and subcortical areas as well as the striate cortex. Of course, if you'd read the article, you would have noticed they mentioned that.
Yes, I read your other comments, including the one where you claim to have read the article. To summarize: you don't think it's possible... because .
Maybe the problem is that TFA tried to make the science more approachable to people, but you obviously don't understand a single thing about blindsight. This is nothing new at all. In layman's terms, the participant still experiences visual sensation but not visual perception -- they can still see, but they are unaware of it. What is significant in this case is the extent of the damage to the visual cortex. The sensory compensation of congenitally blind people is incredible, but this is an entirely different phenomenon.
Sight doesn't "occur" in the eyes, but there are a number of subcortical structures the information passes through before it gets to the visual cortex. Which, oddly enough, is exactly what they say in TFA, which you claim to have read. They specifically say that the "visual areas of the brain" did NOT "light up", so I have no clue what you're babbling about.
The entire point of the article is that the extent of subcortical visual processing (which we are unconscious of) is greater than most people realise. So feel free to read it again and appreciate what is actually a well-established neurological phenomenon.
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Username: arizonafrank
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No existe.
I call it being able to hear the "sound shadows" of objects, because that's really what they are - an object blocks sound, and that blockage is projected to the ear. With a good cane, I can navigate around tables, columns, and even position myself relative to peoples' voices to keep myself from running into them. It's quite amazing what you can tell with a good hallway, and a constant sound source (soda/vending machines are good). For example, an open, echoy space usually means a stairwell.
Also, randomness ... the first time I went to post, my screen reader was very sluggish and crashed. I guess Slashdot hates blind Linux users.