What Illusions Tell You About Your Eyes and Mind
March 15, 2008
Looking at the illusion above, it appears that two “donut holes” are changing in an opposite pattern -- when one is light, the other is dark. But the two holes are actually changing together.You see the illusion because your visual system relies not just on color information, but also on contrast information to make judgments. In fact, far from being a minor side effect of color vision, contrast perception is fundamental to the process of vision itself.
I love to look at optical illusions, but did you know that the reason you’re able to see them is because your eyes are making mistakes? Or, put another way, your eyes are doing what they’re supposed to so you can see clearly, and survive, in a fast-paced world.
What You See is Based on Your Past Experiences
Your perceptions of the world, including your sight, are based on your experiences. Without a context to put them in, for instance, the patterns of light that reach your eyes would be meaningless.
Yet, according to an intriguing study in Computational Biology, robots given the ability to process visual cues as humans do were also fooled by optical illusions. The study suggests, then, that the way you perceive the world around you is not hardwired into your brain. Rather, it is continually shaped by what you have seen in the past.
This concept is alluded to in the movie What the Bleep Do We Know!? There’s a segment when a Native American tribe is unable to see the first ships approaching the land because it isn’t something that has ever been in their experience before.
This is true, too, for every one of us. Think about how different YOUR perceptions of the world are from your neighbor’s, your mother’s, or your child’s. And they are different because each of us has experienced different things along our journeys. Someone who spends their free time watching television will, for example, have a greatly different worldview than someone who spends theirs out in nature, or absorbing different cultures.
So when I look at an optical illusion, I first enjoy it just for the fun of it. But then I like to dig deeper, and remember that every moment gives you a new chance to alter and broaden your perception of the world. Ultimately, how you spend each moment will drastically change what you are, or are not, able to “see.”
If you liked the optical illusion above, its creator, Arthur Shapiro, has a Web site with many others that is worth checking out.