The great and powerful Richard Wiseman has been working overtime in keeping me thrilled with his illusions. Here's his latest, and he posted it with the question, "Does this move for you?"
Everything the man throws out there jumps all over the page for me and it never occurred to me that my experience of his illusions isn't universal. Well, it turns out they're not. According to the polls he runs on his blog, up to half of his audience can't see any movement in some of these illusions. While hardly a scientific finding, he's been able to see that these illusions are are not an either/ or proposition. In other words, predicting who'll be able to see them and who won't can't be predicted. So I'm going to throw a bunch of them up here and and you guys if they move for you. I picked these ones specifically because they move for me. If you click on them, they'll show up full-size in another window.
My obsession with these "animated" static images started with this one.
I've been sorting around for an answer for why this image moves so much and I found it. The National Academy of Science has a library of scholarly papers that deal with visual perception. The archives of the National Academy are an information geek's treasure trove. If that weren't enough, I found a great science blog called Neurophilosophy that talks about this stuff less formally.
Now, I've always known that human visual perception is a function of the way our brains are wired. True, it's our eyes that feed the visual stimulus to our brains, but it's our brains that knit the whole mess of stimuli into a coherent narrative. Therein lies the rub.
Human brains evolved to keep us alive as primates first and foremost so they use our eyes to look for patterns and novelty. Just as the T. Rex in Jurassic Park could only see movement, our eyes work in much the same way. Unlike a T. Rex though, we have a brain to oversee the proceedings. When an object stops moving, the visual perceptors in our retinas stop seeing the object and our brains take over. The actual cells receiving the stimulus take a break and the brain steps in and uses what it assumes to be true about a scene to fill in the blanks. Stare at a beige paint chip for long enough and you can see this retinal fading in real life. The minute the view changes though, the cells in the retina spring back into action and send new information to the brain.
Well it turns out that this rentinal fading may save energy, but it can be an evolutionary disadvantage too. If a predator is stalking you, it doesn't really go away when it stops moving. To compensate for retinal fading, our brains evolved an ability to to issue a wake up call to those napping retinal cells and that wake up call is called a microsaccade.
Microsaccades are rapid, imperceptible (the brain adjusts for them), jerking eye movements. Human eyes exhibit these microsaccades all the time and they allow us to perceive stationary objects, among other things. It's also these microsaccades that are making these images move. Sometimes, an image has the right combination of fine lines and contrasting colors to override the mechanism the brain uses to adjust for the microsaccades it triggered in the first place. The result is a static image that appears to move.
Pretty slick. So what's this have to do with designing interiors? Everything. Design plays with perception, not vision and understanding perception is the name of the game. When you know where the chinks in the armor of perception are, you can exploit them. Besides, this is fun.
Now back to my original question, who sees which of these images move?