New Study Suggests The Stomach -- Not The Heart -- Offers Greater Lie Detection Accuracy

To test their hypothesis that the gastrointestinal tract is uniquely sensitive to mental stress because of the communication between the central nervous system and the enteric nervous system, researchers at the University of Texas Medical Branch recruited sixteen healthy volunteers to undergo simultaneous electrogastrogram (EGG) and electrocardiogram (EKG) recordings for three periods.

The researchers found that both lying and truth telling affected cardiac symptoms, while the act of lying was also associated with gastric symptoms. The EGG showed a significant decrease in the percentage of normal gastric slow waves when the subject was lying that corresponded to a significant increase in the average heart rate during the same situation.

"We concluded that the addition of the EGG to standard polygraph methods has clear value in improving the accuracy of current lie detectors," said Pankaj Pasricha, MD, University of Texas Medical Branch. "The communication between the big brain and the little brain in the stomach can be complex and merits further study."