In a recent study published in the journal Sex Roles, researchers gave 293 college students a lengthy behavioral questionnaire and hooked some of them up to a (secretly non-functioning) lie detector. While the polygraph had no effect on reports of writing poetry, wearing dirty clothes, or telling obscene jokes, it made a difference for sexual behavior. When not connected to the lie detector, men reported more sexual partners and women reported fewer. But when they were hooked up and thought they had to be truthful, women reported having more partners than men!

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