You may not have heard of Oliver Sacks (or your knowledge of him may be limited to a brief mention in psychology 101) – but most people have heard of the movie Awakenings (with Robin Williams and Robert De Niro). The movie was based on one of many real-life cases he worked on and wrote about during his long career as a neurologist. He has produced a few books, I believe. I’ve read two of them (An Anthropologist on Mars and The Man Mistook His Wife for a Hat) – and find them absolutely fascinating. They shed light – odd light – on the inner workings of the human brain. Explanations are not always forthcoming in his books (because they often are not known); indeed, the only thing they clarify for me is how very unclear our understanding of the brain is!
But I’m getting off track (in the first paragraph, of all places!). This post is about some thoughts I had as I read a case in An Anthropologist on Mars. The particular case is about a man who was born blind, then received his site as an adult.
I’d actually wondered, as I’m sure many people have, about how wonderful it would be to have your sight “restored” after being blind for years. It must be the most indescribably amazing feeling in the world – to see the world in all it’s blazing, colorful glory, after being stuck in darkness for years and years.
So…. it turns out that is a pretty naive thought. Would you believe that in cases where blind-from-birth people receive site, suicide is common? I don’t remember the statistics exactly. But the thing is – the brain learns to interpret the reams of data streaming from the eyes from day one. After a dozen or so years of age (again, don’t remember exactly, it’s been awhile since I read this), the brain “solidifies” into an adult brain. If certain abilities have not been established before the point of “solidification,” then the “set” brain will not be able to learn them. We’ve all heard of the cases of “wild” children locked in closets with no human interaction for the first 5.. 10… 15… years of their lives. These people never will learn to speak. They can’t learn to speak. Why? Because speech is something that must be learned in the first few years of life, before that solidification point. The same is true for sight. If the brain matures before it learns to interpret “sight” – it will be missing the basic infrastructure necessary to process sight. Therefore, no matter how much “practice” the individual performs – it’s simply impossible to learn those tasks later in life.
Back to the case I read about. The fellow was born blind, and sometime late-ish in life, had the opportunity to undergo sight restoring surgery. I don’t remember the exact circumstances. Obviously, very few blind-from-birth people have a corretable problem like this man did. For some reason, even though his condition was treatable, he slipped through the cracks, and remained blind until adulthood.
So they did the surgury. The big moment came, and they removed the bandages from his eyes. I don’t know what it was like right then, but a year ago I would have imagined the scene to be something like… it was a fairly dark room – wouldn’t want to expose them never-used retinas to anything very intense. He blinks a few times, clearing the blearyness away. The image comes into focus. For the first time, his wife’s face comes into focus, and smiles at him… in wonderment, he looks around. A tear – rolling down a face… “mother? Is that you?”
Sadly, that’s not very realistic. In actuality, it was more…. They take the bandages off. He opens and closes his eyes a few times. An unknown sensation floods his brain. A complex swarming of irritating flashes overwhelm him. He closes his eyes, breaths for a few moments, slowly opens them – in the mess of stimulation called “vision” he sees a smudge that stands out from the rest. He focuses on it. Suddenly, the smudge changes – it’s moving. Simultaneously with the movement, he hears his wife saying his name. Suddenly it registers – that smudge is his wife’s face, and she’s talking to him. He is again overwhelmed, and closes his eyes.
Again, I don’t remember exactly how it went, but it was something along those lines.
The brain does not have the infrastructure necessary to process the signals from the eyes, and so it is simply overwhemled by the onslaught of information.
It might be easier understand the problem if you consider this. Someone who is blind from birth does not simply “not know what things look like.” Someone who is blind from birth has a far more severe issue: he has no concept of what “look like” is. Color has no meaning. It’s not like he knows what colors are, and simply can’t see them. He has no concept of the very idea of color. Visually, he has no concept of curves or angles. Light and shadows. He has no sense of visual distance. If he sees two cars, and one is 10 times smaller than the other, then it may very well be a nonsensically small car (as opposed to simply “far away”).
When “normal” humans see an object from one angle, we can generally recognize the object from any angle. We take this ability for granted – in fact, we never really notice it, but it is actually a result of astounding computational capabilities of the brain. The ability to utilize light patterns, color, past experience and more to subconciously generate fuzzy transformations of the object, and then run incoming data from the eyes through the “database” to see if the current visual image can be associated with any of these tranformed objects – is unthinkably complex. How many terabytes – petabytes – zettabytes – of information does the brain have to sift through? How many nanoseconds does it take to sift the data, making these fuzzy comparisons?
Man, I wonder what programming language…. no no, I wonder what bloody logical paradigm the brain is based on. It sure is heck isn’t binary.
