When you were a kid, doodling away in your art class, there wasn’t too much variation when it came to patterns. You could draw squiggles and you could draw zig zags; these two line patterns were easy to repeat and didn’t look half bad on a piece of construction paper. Now, at first glance, the photo below appears to have a tame variation of both the squiggle and the zig zag, right?
Wrong. This image, first written about by Digg, was discovered by psychologist Kohske Takahashi. It’s known as the “curvature blindness illusion.” As the name suggests, you become blind to the curves illustrated above because of the contrast created by the gray background. (If this image is messing with you, do not look at this carpet.)
Takahashi dug deep into the illusion in an article published in i-Perception. He explains two of the factors why the phenomenon occurs in the study’s abstract.
“First, the luminance contrast polarity of the wavy line against the background is reversed at the turning points,” Takahashi writes. “Second, the curvature of the wavy line is somewhat low; the right angle is too steep to be perceived as an illusion”
This isn’t any old visual puzzle; Takahashi uses over 20 references in his research. He theorizes that our the human mind defaults to visualizing corners instead of curves when it becomes confused. (Still hungry for more optical illusions? These 8 stunning photos will definitely keep your attention.)