Hi everyone,
Here is a BBC article about blindsight....about how the unconscious makes us see things we are not even aware of.
http://www.bbc.com/future/story/20150925-blindsight-the-strangest-form-of-consciousness****************************************************************************
Daniel turned up saying that he was half blind. Although he had healthy eyes, a brain operation to cure headaches seemed to have destroyed a region that was crucial for vision. The result was that almost everything to the left of his nose was invisible to him. It was as if he were looking out of a window, with the curtains drawn across half of his world.
And yet, as Sanders began testing him, he noticed something very strange: Daniel could reach out and grab Sanders’ hand, even when it must have fallen right behind his blind spot. It was as if some kind of “second sight” was guiding his behaviour, beyond his conscious awareness.
They placed a screen in front of Daniel’s blind spot, for instance, and asked him to point at a circle, when it appeared in different places. Daniel was adamant that he could not see a thing, but Weiskrantz persuaded him to just “take a guess”. Surprisingly, he was almost always right.
Clearly, despite his blindness, Daniel’s healthy eyes were still watching the world and passing the information to his unconscious, which was guiding his behaviour.
Just how many of our decisions occur out of our awareness, even when we have the illusion of control? And if the conscious mind is not needed to direct our actions, then what is its purpose? Why did we evolve this vivid internal life, if we are almost “zombies” acting without awareness?
“What you want to do is to look at something that is as close to consciousness as possible, but which is lacking that specific quality, that subjective experience,” says Christopher Allen at Cardiff University. “And that’s what blindsight gives you. The participant is still perceiving, but they lack awareness of perception.”
..he was blind across the whole of his visual field, and normally walked with a white cane. But the team took away his cane and then loaded a corridor with furniture that might potentially trip him up, before asking him make his way to the other side. “Despite saying he wasn’t able to see, we saw him shooting by on his very first attempt,” says Tamietto. You can watch it for yourself, on the video below.
Importantly, the participant claimed that not only was he not aware of having seen anything; he was not even aware of having moved out of the way of the objects. He insisted he had just walked straight down the hallway.
To understand how, imagine that you are part of a strange puppet show. You have been blindfolded, and your limbs are tied to invisible strings. Every so often, they are tugged here or there by a hidden puppet master, leading you through a complicated dance. To the audience, it looks like you are in full control of your actions, but you don’t have the foggiest idea of what you’ve just done.
“It shows that awareness isn’t the whole story,” says Tamietto. “Very often we believe we have decided something, but our brain has made the decision for us before that – in many ways, and in many contexts.”
The results were a kind of paradox: even though the participant was still not able to actually see anything, his subconscious discrimination seemed to be quicker. In other words, the subject really was “paying attention” – but without being conscious of exactly what he was attending.
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For information.
Cheers.
Sriram
