Part of the show Around The World Yacht Race Medicine
Traditional lie detector tests measure blood pressure and sweat on the surface of the skin to work out when someone is lying, but scientists writing in this week's Nature magazine have come up with an even simpler technique - thermal imaging. When a person lies they rapidly increase the temperature of the skin around their eyes. Although these changes are not visible to the naked eye, a high definition camera can pick out the tell-tale warming signs in at least 75% of people. It also correctly identifies 90% of people who are telling the truth. Because the technique requires physical contact with the individual or expertise to operate, the inventors suggest that it might be useful at, for instance, airport check in desks.