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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."
I don't doubt it all. Lots of people can. The brain automatically enlists your other senses when one of them isn't working. That's why I think the article is a just a load of BS. I don't think the man saw anything. I think his brain was just able to use his other senses to accomplish the same goal.
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Without a working visual cortex, nothing from the eyes enters the brain. At all.
It would be really nice if hypothesis and biology worked like that, where biology followed our hypotheses, but it doesn't. It would be interesting to see an fMRI, or see if he could navigate the maze with earplugs or some way of throwing off air pressure. Assuming it can't possibly be his eyes connecting to some other part of the brain simply because textbooks say the eyes connect only to the visual cortex is not a safe conclusion.
There's only one way to be certain: repeat the experiment.
I would suggest having the blind man and an average-sighted man separately walk down a very well-lit corridor with randomly positioned (i.e., changing every iteration) obstactles 10 times, recording the amount of time each takes and the number of collisions. Reduce the amount of lighting by some increment and repeat the experiment. Continue reducing lighting until total darkness is achieved.
If the blind man is truly navigating by blindsight, both his course times and collision rates should roughly scale positively with those of the sighted man and inversely to the light levels. But then, that would be using the scientific method like the international team of neuroscientists in TFA (whom you are accusing of incompetence) did, so of course you wouldn't believe it...
Take away a 50+ yo man's sight, and in most cases he won't be compensating all that well with hearing. It's partly accuity -- us old farts don't hear all those nice directional high frequencies as well as we used to; and it's partly about what it takes to learn a skill.
Best to start early, because it will take years of practice to do it well and it may well be that your adult mind, after 50 years of primarily visual processing of spatial information, will have a hard time using auditory inputs for that purpose.
It should be no surprise that a blind man can navigate a maze. Blind men have successfully navigated mazes faster then others for quite a while.
That's because their navigational algorithm is much simpler. put your hand on the right wall and follow it.
You'd be surprised how much easier things can get when you eliminate useless data. This, however, seems to be a more noteworthy experiment in that it was more than just a regular old maze with two ends.
Perhaps this will be the first step in discovering psionic potential? If so, sign me up for multiclassing.
If you can read this, I forgot to post anonymously.
Isn't it obvious or am I missing something here??
Blindfold the blind man and repeat the experiment with/without the blindfold. That will tell if vision is being used in any way.
What about the faces?
The sound hypothesis does nothing to explain how the man reacts to various faces presented to him.
Why is redundancy a mess? A unitary design would be prone to complete failure at even minor damage, so would be selected against.
I would think the blindfold might have a psychological effect. I like the idea with lights much better, so he wouldn't know which is which.