Posted on 12/23/2008 2:18:56 PM PST by decimon
Scientists are reporting the remarkable case of a blind man who can see.
The case involves a middle-aged male physician living in Switzerland, who is known only by the initials "TN." A few years ago, TN had two strokes, one on either side of his brain. The strokes severely damaged the part of the brain primarily responsible for vision, known as the occipital cortex.
Extensive testing of TN confirmed that even though his eyes were just fine, he was completely blind. He couldn't see objects held in front of him and used a cane to get around. Ask him if he could see, and TN would reply, "No, I'm blind."
But neuroscientist Beatrice de Gelder wanted to study TN further. She is affiliated with Tilburg University in the Netherlands as well as Massachusetts General Hospital in Boston. First, she and her colleagues repeated tests on TN to satisfy themselves that he was indeed blind.
Then they laid out an obstacle course in a hallway. The obstacles consisted of everyday objects.
"One was a typical paper basket; one was a stack of books," says de Gelder. "They all had different shapes and sizes."
She then told TN to walk down the hall.
"We didn't give him information about obstacles or anything. So he was not aware that there were obstacles."
So TN walked down the hall, but instead of walking straight ahead, he carefully stepped around each of the obstacles.
"He never touched any of it. We were like totally amazed," says de Gelder, who reports her finding in the journal Current Biology. You can see this test by clicking on the video link above.
For his part, TN was surprised that the scientists were surprised.
"Since he had not seen any object, he wasn't aware of having achieved anything sensational," de Gelder says.
TN has what is known as blind sight, according to de Gelder. Even though the primary part of his brain that processes visual information is destroyed, he still has more primitive parts of his brain intact, and these are capable of doing some visual processing. After all, one of the most basic functions of the visual system is to help an animal avoid obstacles or predators. TN still has some visual abilities — he's just not aware he has them.
Steven Hackley, an associate professor of psychological sciences, says studying patients such as TN will tell scientists about the nature of consciousness.
"The idea is that by comparing the same mental process when it is conscious and when it is not, it will be possible to determine which parts of the brain are essential and how consciousness arises," Hackley says.
Amazing that brain of ours!
Slightly off topic...
I wonder which part of the brain processes and visualizes Man Made Global Warming or other delusions Tree Huggers suffer from? Their afflictions may be treatable.
Science is Awesome
evolutionary biology can be pretty amazing. way cool.
Sounds like a neighbor of mine who when he drives knocks his own mailbox down about once a year.
The cerebedlam.
I know this is a post to myself... I’m not blind!
This guy has an interrupt, a functioning eye and ocular system but has no way to process the info into what we call sight, but can process the info into usable data to avoid obstacles... this is what I thought the article / piece was trying to or did actually say... that being said
What else do we or can we see or not see as determined by or with our “normal” Brains.
Einstein saw things that others could not and described them mathematically so that others could see them as well.
I just love Science, “if” may be for children, “what if” is for Scientists (I wish I were one), but I can be a fan
There is also “echolocution,” in which we use sound to tell the distance from objects, like a bat does.
If the tests were done with his ears plugged, then I’d be impressed, otherwise, it was done, at least in part, by echolocution.
What about Demrats to help them with their mental condition. What a wonderfull world it would be ...
As long as we are being funny... this guys condition is not all that unusual, my Wife has it as well, my proof
(1) She married me, and even without glasses you can tell there must be a disconnect somewhere
(2) Just look at her car, she has to be blind... she can run into things that never even thought about being in the way
The cerebellum (Latin for little brain), Cerebedlam must refer to a really really little brain? ;)
I'm not sure where it is, but I'm 100 % sure it's connected to the part that processes BDS syndrome
That is amazing. Gotta give all the credit in the world to a kid who won't be hobbled.
I recall a guy who made a device with 'fingers' that he attached to his back where the skin is sensitive. The device was connected to sensors that would trigger the device to tell him if there was anything solid ahead of him. He blindfolded himself for, IIRC, two weeks with this device attached and said he was developing a sense akin to sight.
Certainly a confused brain.
Even though the primary part of his brain that processes visual information is destroyed, he still has more primitive parts of his brain intact, and these are capable of doing some visual processing.Yeah, okay.
Is he collecting disability checks? That would explain it.
;-)
"The idea is that by comparing the same mental process when it is conscious and when it is not, it will be possible to determine which parts of the brain are essential and how consciousness arises," Hackley says.
Here's a tip. Mind does not arise from the brain.
"...We were like totally amazed," says de Gelder,...
It's nice to see that Valley Girl Speak has not only made it to Switzerland but into a scientist's vernacular. /s
bmflr
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