One study found that watching funny films may improve your job performance if your work involves creativity and solving problems with more than one possible answer—and if you happen to be male. Allan Filipowicz, of INSEAD, showed students a short comedy tape—a clip of Bill Cosby or the movieLiar, Liar—or a neutral video, then had them build a styrofoam bridge or tower that was as long and aesthetically pleasing as possible. Men who viewed the funny film did better than men who viewed the neutral one, but women who saw the comedy tape performed slightly worse than those who didn't. Unlike women, men became more alert after watching the comedy clips, sparking creativity.
Bruce Avolio, directorof SUNY-Binghamton's Center for Leadership Studies, notes that telling jokes can boost leaders' skills, too, if their managerial style is transformational—meaning they urge workers to question norms—or if it's laissez-faire—that is, they leave workers alone. But his office surveys also show that humor hurts "contingent reward" leaders—those who ask workers to obey explicit instructions—since it distracts employees from following strict orders, says Avolio.
The punch line: "Humor's effect depends on the task," says Filipowicz. "If you're doing something creative, you might want to use it. Otherwise, you might not."