Why was the polygraph developed through criminal psychology?

Poly detection as a technology originated from early experimental research in psychology. In 1895, Italian criminal psychologist C. Lombroso used scientific instruments for lie detection for the first time. When the suspect was asked questions such as whether he was related to the case or whether he knew the crime, he used a water chart pulse recorder to measure and record the pulse and blood pressure changes of the interrogated person. In 1905, Weltheimer, the founder of Gestalt psychology, first used the psychological free association principle to conduct lie detection experiments. It uses the subject's reaction time after receiving the "key stimulus word" information as a physiological indicator for detection. In 1914, the European Benussi successfully used a spirograph to detect lies for the first time, believing that breathing patterns often changed with lying. In 1917, Marston, a psychologist at Harvard University in the United States, developed a pulse pressure meter, which was used to obtain periodic and inconsistent records of blood pressure changes during lie detection.

The first practical lie detector was invented in 1921 by John A. Larson, who was a medical student at the University of California. Larson's multi-recorder was invented as a combination blood pressure monitor and respirometer, capable of continuously recording blood pressure and respiration. In 1926, American inventor Leonard Kira patented another lie detector. Kira was successfully invented by combining the Larson polygraph and the GSR device. Among them, GSR is the abbreviation of galvanic skin reflex, which is the change in skin electrical conductivity caused by mental stress. The measurement technology of this physiological indicator was invented as early as the end of the 19th century. In the 1920s, Officer Kira was Larson's early assistant when he was taking polygraph tests at the Berkeley, California, police department. Kira polygraphs with three input channels were quickly approved for use in criminal pre-examinations and employee recruitment or theft control in commercial organizations. In 1945, Kira's assistant John Reed summarized the work of his predecessors and used a Reed-type polynomial recorder of his own design to conduct a polygraph experiment. This instrument can simultaneously record the blood pressure, pulse, respiration, skin current and muscle activity of the subject under interrogation. At that time, pneumography was used, and the Reed polynomial recorder was also called the second-generation polygraph.

In the early 1960s, due to the rapid development of electronic technology, modern recorders and polygraphs appeared. Thermistors, photoresistors, and piezoelectric crystals can all be used as transducers. The transducer, amplifier, filter and electromagnetic sensitive recording pen constitute an electronic multispectral recorder with strong anti-interference ability, which can be called the third generation lie detector. In 1966, a number of polygraph organizations combined to form the American Polygraph Society. The society helps examine the use of lie detectors.

In the 1960s, the U.S. military presided over the development of a covert lie detection device. It used a complex optical scanner to measure the degree of pupil dilation, an infrared scanner to monitor skin temperature, and a microwave interferometer to measure Smooth breathing and even a human odor detector. This polygraph is characterized by its complex equipment and high price. It can perform non-contact polygraph detection, but it cannot detect polygraphs on people who are not present. Among them, Bender discovered in 1933 that the iris of the eye is controlled by autonomic nerves, and strong emotions will cause it to expand. Eicher confirmed in 1951 that strong emotions lower the temperature of the hands and face. In the 1970s, a new breakthrough in the history of polygraph detection was the two-type voice stress analyzer called the fourth-generation polygraph. In 1972, three people including Alan Bell from the United States invented the psychological stress analyzer and obtained a patent in the mid-1970s. It detects frequency modulation caused by micro-jitter in speech for the purpose of interpreting polygraphs. A few years later, Frand Fleuris invented the Voice Stress Analyzer. It detects low-frequency amplitude modulation in the subject's speech. Vocal polygraph testing can use recording equipment, thus allowing the subject to be absent from the scene.

In 1981, the relevant departments of our country introduced two MARK-II sound analysis polygraphs from the United States and initially carried out polygraph experiments and research work. 10 years later, my country's first self-developed polygraph, the PG-I psychological tester, came out. .

In 2001, scientists from the U.S. Department of Defense were developing a laser lie detector that could record a person's level of psychological stress from a distance. At present, the forefront of polygraph research and design is all supplemented by computer processing, and the number of recorded and processed physiological indicators ranges from 2 to 12.

The director of the United States Federal Bureau of Investigation (FBI) came to Le announced on April 3, 2002 that the bureau would take management measures to strengthen internal security, including greater use of psychological testing techniques for employees. Miller said the FBI is studying how to expand the scope of psychological testing among bureau employees and will conduct a trial of the new psychological testing on more than 1,000 employees. Especially after 9·11, many civilian agencies have also begun to implement psychological tests.

For example, in the safety precautions proposed by the US Aviation Security Consultancy Services for aviation safety, psychological testing technology ranks third, with police dogs first and manual inspection second. (DogHanling/Canine Search, Manned Guarding, Polyraph Testing, Psychometric Testing, Recruitment, RisAnalysis, Training: Aircrew, Training: Airport Personnel, Training: Computer Based, Training Aids). Among the terrorist crime prevention measures proposed by South Africa, psychological testing technology ranks first.

In 2005, Israel developed a new lie detection technology that can determine to the greatest extent whether the test subject is lying. The polygraph technology was licensed to a U.S. company, which has now manufactured new polygraph glasses. It is understood that this kind of glasses integrates core lie detection technology and displays test results through built-in LED indicators. What’s more worth mentioning is that its lie detection accuracy is as high as 95%.