Saturday, December 11, 2010

Weird: Dillard's Insight into Sight


In a recent post, I looked at how sight and meaning develop together, that we only ever see a thing with our physical eyes if there’s a corresponding knowledge of it in our brains. But what if the brain develops apart from sight? What if we’re born blind? What then?
What happens then is just downright weird.

If I had to cite only one writing influence in my life it would be Annie Dillard. And if I had to recommend only one of her books, it would be her break-out, Pulitzer-nabbing Pilgrim at Tinker Creek. In it, she writes, among many other things, on the phenomenon of seeing. She refers to an account by Dr. Maurice von Senden of surgeries done in the early 1960s on congenital cataract patients (blind from birth) and writes,

“...The vast majority of patients, of both sexes and all ages, had, in von Senden's opinion, no idea of space whatsoever. Form, distance, and size were so many meaningless syllables. A patient ‘had no idea of depth, confusing it with roundness.’ Before the operation a doctor would give a blind patient a cube and a sphere; the patient would tongue it or feel it with his hands, and name it correctly. After the operation the doctor would show the same objects to the patient without letting him touch them; now he had no clue whatsoever what he was seeing.”

It sounds crazy. A blind person touches a ball and a cube. He’s given sight but can’t tell by looking which is which. The problem with our understanding of what’s going on here is that we can’t separate out the experience of shape without sight. The two are too closely tied. Try it yourself. Put something in your hand and close your eyes. The skin of your fingers and palm, the muscles of your arm holding the object’s weight are drawing on visual sense memory to “create” an image of the thing in your hand. Your brain can do that because the visual information is there and retrievable. For a person blind from birth, there are no such files to draw from. But there are plenty of touch files. So the newly-sighted patient looks at the sphere and cube, and shrugs. But he reaches out a hand and touches them, and knowledge is there, as instantly as turning on a light in a dark room.  

Their perceptions of themselves occupying physical space were just as bizarre as the ball and cube. Dillard writes:

“Of another postoperative patient, the doctor writes, ‘I have found in her no notion of size, for example, not even within the narrow limits which she might have encompassed with the aid of touch. Thus when I asked her to show me how big her mother was, she did not stretch out her hands, but set her two index-fingers a few inches apart.’ Other doctors reported their patients' own statements to similar effect. ‘The room he was in ... he knew to be but part of the house, yet he could not conceive that the whole house could look bigger. . .Those who are blind from birth . . . have no real conception of height or distance. A house that is a mile away is thought of as nearby, but requiring the taking of a lot of steps. . . . The elevator that whizzes him up and down gives no more sense of vertical distance than does the train of horizontal.’”

Reach out and touch the screen or the coffee cup in front of you. The thing only exists for you in space because you know space visually. Your arm is extended out, slightly down, and touching the coffee cup, and you can imagine it sitting on your desk 18 inches away because the knowledge of physical space is already there. You know the context. But what immediate knowledge does a blind person have of such an object? The knowledge of hard, smooth, and cool, of arm muscles contracting a certain way--all touch sensations that don't have anything at all to do with space. Imagine, if you can, a brain formed in that way, for which sensation is primarily touch and feel. There could be no perception of space (as the sighted know it) because space is purely perspective and perspective is purely visual.

I look at my screen now, and can see the edge of a picture frame. I know the monitor hides the rest, the image of Elizabeth, because the idea of space and that something can exist behind something else is a visual thing. Now try to imagine--and you can't, but try anyway--by sense of touch alone, something hidden behind something else. If you're a seeing person, or even if you've not been blind for life, you can't do this without bringing in the visual. You can't do it because the whole phenomena, for us the sighted, is one of perspective. And your perspective is based on visual perception. Even with your eyes closed, it’s based on memory of your visual perception. Ideas like behind, in front of, and hidden only exist as a function of perspective.

One more thing. Of the accounts of Jesus healing folks while he was here on earth, I’ve always thought this one strange: In Mark 8, Jesus heals a man of blindness. He does it in stages, and after the first round of spitting and laying on of hands, the man says to Jesus, “I see men, but they look like trees walking.” Like trees? Until I’d thought about these matters of sight and blindness and perception, that always sounded strange to me. Trees. It doesn’t anymore. It makes perfect sense. A tree to a person born blind is man sized, limbed, up and down. So I thought this especially fascinating: Dillard, quoting von Senden, writes, “One girl was eager to tell her blind friend that ‘men do not really look like trees at all.’” hmmm.

Told you it was weird.



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