No such thing as a break in a curveball?

The answer to the question of whose curveball breaks harder -- that of the Yankees' A.J. Burnett or the Phillies' Cole Hamels -- may be neither. Zhong-Lin Lu, a professor of cognitive neuroscience at USC, along with USC alumni Emily Knight and Robert Ennis and Arthur Shapiro, associate professor of psychology at American University, developed a simple visual demo that suggests a curveball's break is, at least in part, a trick of the eye.

Their demo won the Best Visual Illusion of the Year prize at the Vision Sciences meeting earlier this year.

Try it at http://illusioncontest.neuralcorrelate.com/2009/the-break-of-the-curveball/.

The idea is that the effect is due to the batters being forced to switch between peripheral vision and central vision during a swing.

Source: University of Southern California