Using the relationship between emotion and physiological changes to identify lies

There are two ways to identify lies by using the relationship between emotion and physiological changes. The first is to let the suspect eat rice cake and observe his performance of swallowing the cake under the pressure of strong guilt. If the suspect chokes on the cake, he is considered a liar. The second is the "trial of chewing rice", that is, let the suspect grab a handful of fried rice into his mouth, chew it and spit it out immediately. If the person can spit it out immediately, it is proved to be honest, otherwise it is a lie. The principle is: those who tell lies and worry about being detected are more nervous, their digestive function is inhibited, and their saliva secretion will be reduced, so it is more difficult to swallow cakes and spit out fried rice; those honest people will not feel nervous, so their digestive system will not be inhibited, and their saliva secretion is normal, so they can swallow and spit out food more smoothly.

The British judge whether the suspect is lying by observing how well he eats bread and cheese; the Arab nomads judge the truth of the testimony by licking the burned iron bar with his tongue before testifying. It can be seen that it is an effective method to use the other party's guilty heart to break his lies.