A lie detector can tell whether a person is lying. How does it work?

Lie detection is a different activity of lies. The word "lie" comes from "lie detector"; Directly translated as "multi-recorder", it is an instrument for recording various physiological reactions. You can use it to help check the psychological state of suspects in criminal investigation, so as to judge whether a criminal case is involved.

Because the real suspect lied this time, which is said to be a "lie". To be precise, it is the change of physiological parameters caused by stimulating the heart. So it should be called "multiplier psychological test" scientifically and accurately.

Polygraph structure

Modern time delays include sensors, mainframes and microcomputers. The sensor is connected to the surface of human body to collect the information of human physiological parameters; The host is an electronic component, which converts the analog signals collected by the sensor into digital signals; The microcomputer stores the input digital signals and analyzes the results.

For example, it is only 32 books in size and consists of three parts: sensor, host and microcomputer. The sensor has three tentacles: the skin electric sensor worn on human fingers is a stainless steel electrode, which is used to measure the change of skin resistance; Breathing sensor is a kind of stretching sensor, which measures the changes of human chest. Pulse and blood pressure sensor is a pressure-sensitive sensor or sphygmomanometer worn on a person's wrist or arm to measure his pulse and blood pressure.

The function of the upper computer is to convert the analog signals collected by the sensor into digital signals, which are stored and analyzed in the computer. It is precisely the deceleration technology, which is a psychological test technology. The so-called psychological testing technology is to combine bioelectronics with psychology and complete the analysis process of human psychology by computer means. According to psychological theory, everyone has experienced a certain event and left an inevitable mark without exception.

After the crime continues, the Committee will continue, and various crime scenes will be reproduced repeatedly in the heart. They think about what they might leave behind, even if they don't think they can't restrain themselves. Whenever the details of some cases are mentioned in the scene, the crimes of this brand will be exposed through various biological reactions, such as breathing due to shock, pulse and skin. After recording the test instrument, record this subtle reaction and form or inform or involve conclusions.