Home_____Blindsight: Graham Young Is Blind But Can See

What is consciousness? You may say that it is to be aware. But what does it mean to be consciously aware of something? I can type this paragraph while outside my window a bird chirps, shadows dapple the window ledge, and here, inside, my fingers move on the keyboard, music plays on the radio, and so many other events also happen as I focus only on these words. I stop for a moment, and there they are, all these other things. Then I return my attention to the computer screen. In a sense, I see but I don't see. I am aware but I am not aware. Things are part of conscious and, so to speak, they are not.

Graham Young of Oxford, England is a case in point. When eight years old, he suffered a head injury that damaged the visual cortex of his hind brain, and this experience rendered him unable to see on his right hand side, while he can see on his left. This blindness affects both eyes.

He has a condition called blindsight, a term coined by Professor Larry Weiskrantz of Oxford University, and it has made Young a prime candidate for neuroscience experiments, particularly because his damage is quite specific and localized, making his situation one of the purest examples of a very rare condition.

If you put an object on his right side and ask, "What is it?" he cannot say.

If you move it, and ask "What direction?" he can tell you. Up, down, left, right. He can do this even though he cannot see the object.

If a neuroscientist moves an object to his left side, he will see it. As the experimenter moves it to his right he will announce the point at which the object disappears from his view. So long as the object remains motionless, Young can only say nothing is there. When a tiny light is moved, he can announce its direction, although he cannot see it. More



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