| Having congenital Glaucoma, I've always had to live with the possibility of one day being blind. My left eye is already pretty much there. What has always fascinated me about sight is how our brains augment and outright invent things you think you see with your eyes. It's not at all about believing what you see, but about seeing what you believe. The Glaucoma has steadily been eating away at my retina and optic nerves over the many years. Causing blind spots to form all over my visual field. In daily life, I can't see those spots. As in, there are not actually black holes in the images I perceive. The brain somehow manages to fill in those gaps with visual information directly surrounding those gaps and combine it with what my experiences/memories tell me should be there. It's only when I start concentrating on really small details, that these holes become apparent. Particularly when looking at small LED lights in a dark environment. The LED keeps disappearing and reappearing as I slowly turn my head in various directions. Everybody has a single blind spot like this in the center of their visual field which behaves in the same way. Imagine this, but multiplied over 60 - 80% of your visual field. Additionally, my almost-blind left eye has caused me to lose depth perception all together. This means those fancy stereoscopic 3D things are pointless to me and one would expect I would have a hard time in traffic. Not being able to judge the distance to an oncoming car can be deadly. But again, the brain seems to draw on its memories and years of experience and somehow manages to account for the lack of depth perception. It's not perfect, but enough to cope in daily life and safely move from A to B. At least on foot, that is. I am not allowed to drive a car for obvious reasons. A moped is technically permitted, but I don't. It moves too fast for me to accurately judge my surroundings in time. The same even goes for a bicycle. I only ride those in daylight. Not at night. As far as blindness goes, I've had this once. As a kid, I fell out of a tree and landed flat on my back. For the following 45 minutes I was completely blind. It freaked me out to no end, as I was terrified it would not go away. Luckily it did. Not looking forward to that again! |