PeerJ launched today (congrats!) and one of their very first published papers is about the science of magic! “Perceptual elements in Penn & Teller’s “Cups and Balls” magic trick” studies how people are fooled by a sleight-of-hand trick involving cups and balls.
The magician makes balls suddenly appear underneath cups, or has them move through the bottom of a cup. Here’s a video of Penn and Teller performing the trick in question:
In this study, researchers replaced the standard opaque cups with transparent cups, and research subjects were asked to watch videos of Teller performing the trick and report whenever a ball was removed from cups or placed under cups. Unsurprisingly, this was easier with transparent cups than opaque ones, but for two variations of the trick, people still had a difficult time spotting where the ball went. Those were not the variations that Teller thought would be the most difficult to spot, and the researchers conclude that “Our combined results have implications for how to optimize the performance of the “Cups and balls” magic trick, and for the types of hand and object motion that maximize magic misdirection”
Rieiro H., Martinez-Conde S. & Macknik S.L. Perceptual elements in Penn & Teller’s “Cups and Balls” magic trick, PeerJ, DOI: 10.7717/peerj.19