Offering a powerful new tool against terrorism, researchers have found a way to detect lies in the liar's blushing  face. The technique, described in the journal   Nature, uses a thermal camera   to detect the sudden shift of blood flow in the face. The system performed as a traditional polygraph  , the scientists report. Pushed by technological advances and with fresh interest since Sept.11, the discovery is part of the development in the scientific study of detection. Although the lie remains a mysterious phenomenon, researchers in recent years have found a number of new methods that might take the place of the polygraph, from brain scans, to slight changes in eye movement, to sparks of electrical activity that signal a person has seen a victim or a crime scene before. The new finding says, when a person tells a lie, there is a sudden change of blood to the area around the eyes. Although the change is not ordinary visible, the blood warms the skin, causing bands of color1 to appear through a camera sensitive to heat.  One advantage of the camera can provide answers quickly, and doesn't require a highly trained expert to operate it or explain its results. In theory, this new technology could be used anywhere large numbers of people need to be quickly screened. But some scientists say the technology would need to be improved before it is ready for use, for it is possible that there are other reactions that cause a sudden change in blood flow in the face and there is also the danger that people will learn to fool the machine, the same way they try to fool polygraph examiners by controlling their breathing or taking drugs to relax themselves. It is NOT true that this new technology   _  .
is incomparable as a result of perfect development and necessary rests is likely to be used widely to screen large number of people faces the danger of being fooled by experienced and drug-taking liars needs to be improved before being put into use