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Collaborators seek way to detect deception
By Sheila Watson
Contributing Writer
Researchers at the Medical University of South Carolina, collaborating with the South Carolina Research Authority’s Biomedical Applications Research Institute, have completed a series of studies on functional magnetic resonance imaging to detect deception in individuals.
Published results of the fMRI studies show a 90% accuracy rate in successfully distinguishing truthfulness from deception in more than 60 participants.
“This is a high-end MRI machine,” said Dave Ramsey, BARI’s vice president of research services. “It’s a much more powerful magnet and gives a better signal quality. As a result, we can see things a regular MRI cannot.”
Moving pictures
Ramsey explained that while a regular MRI is used to produce structural images, such as abnormal tissue growth, a functional MRI is like seeing a movie rather than still photos.
“We look at what happens over time, how blood that is highly oxygenated goes to a low concentration of oxygen,” he said.
When that occurs, it signifies that the brain is consuming oxygen, which indicates a particular area is being activated.
“We’re looking at the blood-oxygen levels over a period of time,” Ramsey said. “When someone is lying, the brain will sort out consequences, what the person has to gain by lying. If there is a spot in the brain making a ‘go or no-go’ decision in a lie, that’s when that area would use a lot of oxygen.”
Dr. Andy Kozel was the principal investigator in the studies. Now an assistant professor at the University of Texas Southwestern Medical Center at Dallas, he remains active in the studies and continues to hold a position as adjunct assistant professor at MUSC.
Kozel was co-author of two papers on the subject, one published in the Journal of Neuropsychiatry and Clinic Neuroscience and the other published in Behavioral Neuroscience. He said he believes the fMRI is more accurate than standard polygraphs.
“It’s hard to get true lie detector results,” Kozel said. “The reason we think it’ll be an improvement is because we’re actually measuring what’s going on in the brain instead of in the peripheral areas. A polygraph measures physiological reactions, such as anxiety, when confronted with a lie.”
The subjects tested were generally considered “healthy,” meaning they were not taking medications and were not determined to have psychological or psychiatric conditions, Kozel noted. Future studies will include subjects with those criteria.
Number crunching
In its support role in the fMRI study, the SCRA’s BARI division has been doing much of the heavy lifting through its Computing and Communications Infrastructure Technology department.
“Deception detection work generates tremendous volumes of data,” said Ramsey. “In the past year, we’ve generated half a terabyte of data. And to then subsequently analyze the data is also an enormous undertaking.”
Ramsey said BARI and CCIT are not only storing, but also sifting through MRI scans to determine which portions of the brain are active and which are inactive during the studies.
“All that processing is done here at SCRA,” he said. “We provide the computing and the tools, and we assist in executing analyses and helping out with statistics.”
The study is being funded in part by the Department of Defense and will be used by the DOD’s Polygraph Institute at Fort Jackson.
“What we’re discovering through this study has applications in terms of counter-terrorism,” said Ramsey. “The users would be intelligence agencies to determine deception in individuals. The types of issues they’re dealing with have worldwide consequences and are potentially life-threatening. It’s important to know whether the data and the person giving it can be trusted. Is this person sending us down the wrong path or giving us accurate information? It’s something we need to know and decide on now.”
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