From Science:
Adventure stories and horror movies ramp up the tension when hapless characters walk in circles. The Blair Witch Project, for example, wouldn't have been half as scary if those students had managed to walk in a straight line out of the forest. But is this navigation glitch real or just a handy plot device? A new study finds that people really do tend to walk in circles when they lack landmarks to guide them. The idea for the study came from a German science television show called Kopfball (literally, “head ball,” as in soccer), which tries to answer viewers' questions, says the study's first author, Jan Souman, a psychologist at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany. The producers contacted Souman and his colleagues, who study perception and action, to find out if the common belief about walking in circles was true. “We didn't really know, but we thought it was an interesting question,” Souman says. So the researchers collaborated with the program, resulting in an episode that aired in 2007.
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