What Fuels Urban Legends?

You've probably heard the one about heavy metal singer Ozzy
Osbourne decapitating rats (or was it puppies?) during concerts in the
1980s.

Urban legends are fantastical stories that spread like syrup among
urban and not-so-urban areas alike. But these anecdotes contradict
sociologists' beliefs about the survival of stories—that they provide
insightful social commentary.

Psychologists at Stanford and Duke universities had another theory.
"We proposed that ideas are selected and retained in part based on their
ability to tap emotions that are common across individuals," explains
Chip Heath, Ph.D., an associate professor of organizational behavior at
Stanford. Heath and his colleagues decided to examine anecdotes that
inspire disgust (some 25 percent of urban legends fit the bill). They took
12 urban legends and presented undergraduates at Duke University with
three increasingly revolting versions of each story. For example, someone
develops vacation photos and discovers that their toothbrush has been
photographed in close proximity to a hotel-worker's (a) fingernail, (b)
armpit or (c) anus.

Amused undergrads consistently repeated the version that elicited
the most disgust. "Emotion matters," says Heath. "It's not informational
value alone that causes these things to succeed."

Many urban legends up the emotional ante by acting as cautionary
tales. "There's the story of sadistic people booby-trapping Halloween
candy," offers Heath, who published his findings in the Journal of
Personality and Social Psychology. "That's classic emotional selection.
It made people less able to trust their neighbors."