Remember that scene in the movie "Meet the Parents" where Robert De Niro gives his soon-to-be son-in-law, Ben Stiller, a lie detector test? Stiller's character is nervous and flunks the test even though he didn't really do anything wrong. Well, that's long been a problem with polygraph tests. They are pretty good at catching liars, but they sometimes wrongly accuse honest people too.
Now science is trying to come up with a better test. For tonight's show, we talked to two doctors at Temple University Hospital in Philadelphia, Pennsylvania, who recently put 11 volunteers into an MRI machine and asked six of them to lie and five to tell the truth to a series of questions. The results are remarkable.
When the volunteers lied, twice as many parts of their brains were active -- about 14 unique areas. But when the volunteers told the truth, only seven areas of the brain were active. Turns out it takes much more concentration to lie and doctors can see the difference using an MRI machine.
The doctors are excited about their research, but stress it is still in the early stages. Nonetheless, I can think of a lot of situations in which this test would be pretty useful -- cheating spouses, criminals, lying politicians. I'll bet you can too.
