This illusion, created by cognitive neuroscientist Ryota Kanai, then at Utrecht University in the Netherlands, was a top-10 finalist in the 2005 Best Illusion of the Year Contest (http://illusionoftheyear.com). Explore the image freely, and you will see a regular pattern of intersecting horizontal and vertical lines in the center, flanked by an irregular grid of misaligned crosses to the left and right. Choose one of the intersections on the center of the image and stare at it for 30 seconds or so. You will see that the grid “heals” itself, becoming perfectly regular all the way through. The illusion results from both perceptual fading and the ensuing neural guesstimates that our brain imposes to “fill in” the outer parts of the image based on the available information from the center, in addition to our nervous system's intrinsic tendency to seek structure and order, even when the sensory input is fundamentally disorganized.
Beauty in the Eye of the Beholder
Artwork may contain “errors” that are obvious to our central vision but become invisible when viewed from the corner of our eye. Neuroscientist Denis Pelli of New York University discovered that Pablo Picasso's Maquette for Guitar (1912) appears absurd only when we look at it directly: the strings are torn and twisted, the neck is crooked, and the body is split into disconnected pieces. But now focus on the cross, while still paying attention to the guitar: all you can see is the smooth curves and elegant angles of a beautiful instrument. Pelli hypothesizes that the illusion works because our peripheral vision confuses the locations of the parts. Failure to notice the errors in the maquette produces the perception of a real guitar. Picasso's paintings of Nusch Éluard, a French acrobat, show a similar phenomenon. When viewed directly, the portraits are grotesque, but when seen peripherally, the young woman looks exquisite. Pelli suspects that Picasso was well aware of this effect.
This article was originally published with the title Vanished without a Trace.