This is the VOA Special English SCIENCE REPORT.
Scientists say they have developed a camera that can help identify when a person is not telling the truth. The new camera measures the heat released by a person's face.
The scientists say the camera correctly identified lying in more than eighty percent of the people they tested. They say the device might one day be used in high-level security operations at airports or border crossings.
James Levine of the Mayo Clinic in Rochester, Minnesota led the study. Nature magazine reported the findings.
The scientists based their work on the theory that people who plan to trick someone release physical or chemical signals. They say these signals can help security officials prevent wrongdoing.
The Mayo Clinic researchers worked with scientists at Honeywell Laboratories to develop the new, heat-imaging technology. Doctor Levine says the camera is designed to measure small changes in the body. He notes that the flow of blood to the surface of the skin increases around the eyes when a person lies.
The scientists used twenty people to test the heat-sensing camera. Eight of the people took part in a crime that was not real. They attacked a human-like object and stole money from it. They were asked to lie and say they were innocent of the crime. The twelve other people in the study were told nothing about the make-believe crime.
The researchers used the special camera while questioning the twenty people about the crime. The camera showed that six of the eight people who carried out the crime had increased heat around their eyes when they lied. Eleven of the twelve people who knew nothing about the crime were correctly identified as innocent. When they told the truth, the area around their eyes remained cool.
The researchers say the rate of success of the test was similar to the current polygraph method of lie detection. Polygraph tests measure changes in heart rate, breathing and the wetness of a person's skin.
However, a polygraph test requires a person willing to be tested. And it takes time and skill to examine the results. Lie detection experts say the new camera could be used without suspects knowing they are being watched. The researchers say more testing and development of the device are needed.
This VOA Special English SCIENCE REPORT was written by George Grow.