Human brain activity is key in deception research
Vendemia's research attracted immediate interest from the federal government in the wake of the 2001 terrorist attacks.
"Screening employees is the federal government's No. 1 motivation for supporting deception research," said Vendemia, whose work has been funded by the U.S. Department of Defense's Polygraph Institute and the National Science Foundation. "The goal is to keep terrorists from infiltrating and undermining the nation's security agencies."
Vendemia's research group used EEG instruments in its early research to map out brain activity; now they also use a powerful Tesla 3 fMRI machine purchased with a research grant and housed at the McCausland Center for Brain Imaging. More than 200 people have been scanned with the device to further the deception research.
What have they found so far?
"We know that someone with a large, active memory has the ability to hold lots of new information, and that person is better at being deceptive," Vendemia said. "Their fMRI scans show that the areas of the brain associated with deception don't light up as fast as with someone who doesn't have the same memory ability."
But the brain activity associated with the decision to tell a lie is revealed on the brain scan, and even the most practiced and casual of lies--telling someone you're fine when you're really not--still shows up on an fMRI scan.
"Quite simply, it takes longer to lie than to tell the truth," Vendemia said. "Of all the studies I've done, this one has produced some of the strongest data I've ever had."
Vendemia's brain scanning can distinguish between someone who is incorrectly remembering something and deliberately deceiving. In fact, a person can be tricked into unintentionally lying by erasing bits of their original memory. Research experiments that involve replacing key details of a crime scene with false information, for example, can alter someone's memory of what they saw. "It shows how key witness testimony can be false," Vendemia said.