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Blind, Yet Seeing: The Brain’s Subconscious Visual Sense
NY Times ^ | December 23, 2008 | BENEDICT CAREY

Posted on 12/23/2008 10:55:58 PM PST by neverdem

The man, a doctor left blind by two successive strokes, refused to take part in the experiment. He could not see anything, he said, and had no interest in navigating an obstacle course — a cluttered hallway — for the benefit of science. Why bother?

When he finally tried it, though, something remarkable happened. He zigzagged down the hall, sidestepping a garbage can, a tripod, a stack of paper and several boxes as if he could see everything clearly. A researcher shadowed him in case he stumbled.

“You just had to see it to believe it,” said Beatrice de Gelder, a neuroscientist at Harvard and Tilburg University in the Netherlands, who with an international team of brain researchers reported on the patient on Monday in the journal Current Biology. A video is online at www.beatricedegelder.com/books.html.

The study, which included extensive brain imaging, is the most dramatic demonstration to date of so-called blindsight, the native ability to sense things using the brain’s primitive, subcortical — and entirely subconscious — visual system.

Scientists have previously reported cases of blindsight in people with partial damage to their visual lobes. The new report is the first to show it in a person whose visual lobes — one in each hemisphere, under the skull at the back of the head — were completely destroyed. The finding suggests that people with similar injuries may be able to recover some crude visual sense with practice.

“It’s a very rigorously done report and the first demonstration of this in someone with apparent total absence of a striate cortex, the visual processing region,” said Dr. Richard Held, an emeritus professor of cognitive and brain science at the Massachusetts Institute of Technology, who with Ernst Pöppel and Douglas Frost wrote the first published account of blindsight in a person, in...

(Excerpt) Read more at nytimes.com ...


TOPICS: Culture/Society; News/Current Events; Testing
KEYWORDS: cva; health; medicine; vision
Intact navigation skills after bilateral loss of striate cortex
1 posted on 12/23/2008 10:55:59 PM PST by neverdem
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To: neverdem

bttt


2 posted on 12/23/2008 11:00:40 PM PST by RebelTex (:^D)
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To: neverdem

That’s pretty cool

I imagine that would be pretty devastating to anybody. I couldn’t imagine not being able to weave through pedestrian traffic, floating on my feet. Or being able to navigate a down hill on my bike.


3 posted on 12/23/2008 11:06:08 PM PST by wastedyears (In Canada, Santa says "Ho Ho, eh?")
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To: neverdem

I wish someone would test me for something similar, but different.

I lost my sense of smell in an accident yet my sense of taste is more acute than most “normal” people.

[i.e. I got food poisoning from chicken salad that *I* thought ~tasted~ weird but hubby had ~smelled~ and declared “perfectly fine”]

My crazy theory is that my “wires got crossed” and that I *can* smell but the signals that process a smell into consciouness are not being recieved normally, any more.

No neuro-doc has ever been able to explain it and I know several people who lost their sense of smell to similar injuries and they can’t taste *anything*.


4 posted on 12/23/2008 11:12:32 PM PST by Salamander (Cursed with Second Sight.)
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To: neverdem

my wife says I drive like that...


5 posted on 12/24/2008 1:56:16 AM PST by rusureitflies? (OSAMA BIN LADEN IS DEAD! There, I said it. Prove me wrong.)
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To: Salamander

I too have lost my sense of smell — I can’t even smell a skunk.
But I can taste food — while taste uses the sense of smell, the taste buds in the mouth are an independent system from the smell receptors.

So - why do you think it’s unusual that you can taste things? I realize, i.e., that you (like me) can’t taste some things, i.e., I can’t detect sour/spoiled milk, for instance.

But I have great appreciation for spicy foods, curries, pepper, etc.


6 posted on 12/24/2008 2:28:47 AM PST by WL-law
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To: neverdem

Can anyone spell synethesia?

http://en.wikipedia.org/wiki/Synethesia

Cheers . . .


7 posted on 12/24/2008 3:31:22 AM PST by admiral52 (Vanity license plate: IMGPNG)
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To: Salamander

Talk about useless super powers:

I can identify a person by their voice after hearing them once - even when they purposely alter it. People freak when I instantly name actors voicing animated characters. It’s not perfect - Mark Hamill’s control over his vocal cords makes most everyone astonished when he does the Joker.

This ability to navigate without inherent sonar reminds me of the DareDevil, a comic book character who’s power to see without sight is usually laughed off as too preposterous for suspended disbelief.

Who’s laughing now?


8 posted on 12/24/2008 5:24:41 AM PST by NewRomeTacitus (Cat Juggling!)
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To: admiral52

Thanks for the link. Merry Christmas - Happy Chanukah!


9 posted on 12/24/2008 10:30:52 PM PST by neverdem (Xin loi minh oi)
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