Sunday, March 21, 2010
You've got one, so do I. All humans have an anatomical blind spot, a section of the visual field where there are no rods or cones, hence no sight. According to wikipedia, the anatomical blind spot is:
The optic disc or optic nerve head is the location where ganglion cell axons exit the eye to form the optic nerve. There are no light sensitive rods or cones to respond to a light stimulus at this point. This causes a break in the visual field called "the blind spot" or the "physiological blind spot."
So why isn't there a blank spot when I look up at the tulip magnolias or stare at the Capitol Dome?** The cool thing is, the brain adds very substantially to the data it receives from your eye. Your brain decides what you should be seeing, what you would be seeing if you could see with your blind spot. In fact, the brain goes far beyond the blind spot while creating the visual field. A lot of what you see is made up by the brain. A lot of what you don't see is "invisible" because your brain decides you don't have to see it or it doesn't matter or doesn't fit in with your world view. These facts beg the question, is there any such thing as an objective reality? I think not!
We are such creative beings, we humans. We make (and later sweep up) sand mandalas, we knit, spin, take photographs, write poems, paint paintings, draw, cook, garden, sing, play instruments. A part of every endeavor involves a blind spot of one kind or another that we compensate for in some way as part of the creative experience. It is our habit to fill in the blank spots, to make our lives seem continuous, to make our personal stories seem fully fleshed out. Perception, in fact, involves a whole lot of conjecture.
This talent of ours, and our tendency to believe the stories we tell ourselves, gets us through the day, so that's a good thing, right? I say yes. Maybe the important thing to remember is that no one else shares exactly the same perception of the complexities of this world. Do you think any member of Congress can remember that today? Hmmm....
**I'm staring at the Capitol dome because I really really really hope Congress passes the health care bill today. I believe if I stare hard enough, they'll HAVE to. I'm certain there's a blind spot in this concept you could drive a truck through. Oh well.
Two lovely pregnant women at Lincoln Park, with their partners.