If you want women to do poorly on a math test, tell them they're genetically inferior to men.

That's the finding of a new study in the journal Science (not yet available online) that confirms the existence of a "stereotype threat" that disrupts the performance of people who are reminded of a stereotype about them.
"They end up performing worse and 'proving' the stereotype," a study co-author told HealthDay News. "In this way, theories about how people behave can end up influencing how they behave."