The Best Illusion of the Year was just announced, and the grand prize goes to a trippy demonstration of how curve balls flummox batters. Four visual researchers--Arthur Shapiro, Zhong-Lin Lu, Emily Knight and Robert Ennis--collaborated on the illusion.
The winners resolve a conundrum that baseball players have always faced: The "break" in a curveball. A curveball occurs because of the ball's topspin, but it curves gradually during the baseball's flight, and by just a couple feet. But for batters, the ball seems to jump several feet nearly instanteously. The illusion by Sharpio et al shows that crazy things happen when you switch from your peripheral vision to your central vision; objects can appear to move more than they actually do. A curveball can appear to break. Still images can't convey how bizarre the effect is, watch the animation here.
The award, which is given away each year at the Vision Sciences Society Meeting, wasn't just a lark for the the participants. Illusions have long been used to test exactly how our vision works, and the competitors were mostly scientists who've recently published their illusory findings in academic journals. Second place went to an experiment in creating "afterimage" colors; third prize went to a demonstration that simply changing the contrast on an androgynous face chances whether we see it as female or male:
You can see the list of ten finalists here.