Hi everyone,
Here is a CNN article about a peculiar condition of seeing without 'seeing'. The Unconscious mind again.
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?
“And that’s what blindsight gives you. The participant is still perceiving, but they lack awareness of perception.”
Weiskrantz’s team put another blindsight patient through the most gruelling test yet. Unlike Daniel, 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.
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.
one subject was able to distinguish movement in fast, high-contrast films; he described it as being like “a black shadow moving against a completely black background” – a “sense of knowing” that there was something beyond. But even then, he could not describe the content itself, meaning that his experience lacked almost everything we would normally associate with vision. “There’s a lot of controversy about whether those reports truly reflect visual experiences,” says Kentridge.
Picking apart the experience may also reveal further clues about the power of unconscious mind. 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.
That puppet show is essentially what happens when someone with blindsight navigates their way past obstacles – with the non-conscious mind acting as the puppet master. “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.”
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For information.
Cheers.
Sriram
