Chapter 6

I think our vision is so easily tricked because all of the many complex and interacting systems we use to see and perceive have been so specifically refined and trained to do what they do. Once figured out, an optical illusion can be tailored to trick any one of those particular systems. An optical illusion is immediately taken in by the eye and processed by the brain. I think it’s only then that as the brain thinks about it, what we were tricked into initially seeing would be realized by our brain as it works through the information and fills in the blanks or corrects what we are seeing. Like those dark spinning tubes with dotted light and a bridge going across. Even though I know what they do, I still find myself falling over every time before my perception has time to adjust. Then I can walk fine. But one time I glanced over my shoulder after I had stepped off the bridge, and even though I was standing fairly still, I immediately started falling over again.

It goes to show how incredibly adaptive our vision is. The length of the section dedicated to explaining vision alone, with the many subsections to the subsections explaining structure, processes, constancy, how it’s all organized, and finally how it is interpreted. Our eyes work to adapt quickly, whether its an optical illusion, catching a ball, adjusting from dark to light, recognizing a familiar face in a crowd, walking through a world flipped upside down, even just recognizing motion or three-dimensional objects. The brain adjusts accordingly.