Moving Non-GIF pictures

Beware: Headache causing images ahead!


Niether of these pictures are GIF's, but they still move nonetheless. Just try staring straight into the middle of the first picture...and then in the second picture look at each circle individually and then just look at the side of the picture (note that they'll move more for some people than others). Ouch.

So, if you're wanting an explanation...I'm not giving one.

...Kidding. ;-) Carl Zimmer from Discover Magazine will explain for me though:

"As you’ll notice, the circles seem to rotate in response to where you look at the illusion. So [Stephen] Macknik and his colleagues tracked the movement of people’s eyes as they gazed at two of these wheels on a computer screen. Their subjects kept a finger pressed on a button, lifting it whenever they seemed to see the wheels move. Macnick and his colleagues found a tight correlation between the onset of the illusion and a kind of involuntary movement our eyes make, known as microsaccades. Even when we’re staring at a still object, our eyes keep darting around...the pattern of colors and contrasts in the Rotating Snakes Illusion causes our eyes to send rapidly changing signals to the brain even during microsaccades. The motion neurons switch on, and the snakes start to slither."

Pretty neat, huh?

- Via Mighty Optical illusions