Functional Magnetic Resonance Imaging may promote theoretical understanding of the Polygraph Test

Concerns about the validity of the comparison question test (CQT) will continue to create controversy until a well-validated theory is developed that explains how the polygraph test detects deception. One theory that provides a plausible explanation states that deceptive behavior on the CQT and corresponding physiological arousal on the polygraph are associated with neural activation in areas of the brain that process personally-relevant, emotionally-arousing information. Although the literature on functional magnetic resonance imaging (fMRI) and the detection of deception suggests that certain brain areas may be active when someone lies, no study has examined whether deception on the CQT produces activation in specific areas of the brain and corresponding physiological arousal as measured by the polygraph. Using fMRI to test Kleiner's theory may provide support for his theory of how the polygraph detects deception and may also improve the predictive validity of the CQT.