TIL about blindsight, a phenomenon by which visually blind people can apparently see or detect objects without using their visual cortex
TIL about blindsight, a phenomenon by which visually blind people can apparently see or detect objects without using their visual cortex
It was a footnote in an article I read about a monkey using blindsight and that there had been several experiments with humans proving blindsight existed and that surprised me. As a footnote.
There have been several experiments that indicate people can see without using their visual cortex.
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This would've made a nice chapter in books by Oliver Sacks
Also, there's the "Controversy" that states some scientists consider blindsighted people to not be blind. I'd say it is the same as with other cognitive issues, one may technically not be blind but how would you call that when one cannot use their sight if not blindness
I looked into the controversy articles that people wrote, and they were mostly saying that if certain conditions were satisfied then it might not be blindness, even though they did replicate the experiments the other scientists did and got the same results.
The scientists objecting are, as I understand, saying that because of a third test they devised, then it could be argued that it isn't technically "sight".
But the controversy is a lot weaker in my mind from what I've read the repeated abstracts and experiments over the last 50 years that document blindsight.
One of the articles specifically mentioned a part of the brand that isn't the visual cortex that frogs and animals can use to see objects even if they are completely blind, and that's why they did the tests with the chimpanzee in the first place, because of a frog can do it, why not a chimpanzee.
I can't tell from what I've read if humans are supposed to have this same ancient component that lower animals do, but I assume I'll be able to find out if I keep digging.
Thank you for providing insight.
What I mean is more that things related to consciousness, subjectivity, and qualia are rather loosely defined and aren't guaranteed to have any measurable and good definition
You're right, something vaguely defined can definitely have that problem.
Blindsight stood out to me a significant because the visual cortex is damaged, not functioning or missing all together and there's a part of the brain that works with lower(and higher) animals that apparently allows them to see still, somehow.
If it was a matter of definition, like "degraded sight" versus "partial blindness", I would nou have found this as compelling and certainly not noteworthy enough to post.
But if you are missing the part of the brain that processes sight, or are missing an eyeball... I believe one of the test participants had his actual eyeball destroyed.
If it's the physical lack of a processing unit and still we get the result of apparent sight and there is no conclusive scientific objection to half a century of scientific experiments measuring how much blind people can see, that's fascinating to me.
Actual eyeball destroyed should not allow to percept anything I think, but I don't know of course
Other than that, as a layman, I would expect there to be some automatic and autonomous stuff related to vision but not requiring conscious results. After I learned of some processing done right in the eye (can't find the link, it was some experiment on cat eyes) I'm more inclined to think that a lot of processing is done out of consciousness, or sometimes even brain