From the website:
"While many studies have shown the ineffectiveness of polygraph lie detectors for determining people’s truthfulness, courtrooms still look to science for help in assessing the testimony of suspects and witnesses. Now, neuroscience may be the key, enabling a new breed of lie detectors that look directly into subjects’ brains.
"An fMRI (functional magnetic resonance imaging) device registers blood flow within a subject’s brain to map its activity—the more blood that an area of the brain is getting, the more active it is. This differs completely from a polygraph lie detector, which measures pulse, heart rate, breath rate, and any perspiration.
"In a paper for the International Journal of Liability and Scientific Inquiry, law professors Edward Johnston and Daniel Jasinki of University of the West of England discuss the use of fMRI in criminal proceedings. They suggest that investigators could use fMRI to evaluate which areas of a witness’s brain light up during an interrogation: More activity in the memory area could indicate honesty; more activity in the creativity area would suggest fibbing. Such tests could also gauge jurors’ emotional responses, thus detecting bias."
Link to full paper provided in article.