Lie detecting can be tricky. Sometimes, by observing behavioural patterns or mannerisms of body also, it gets difficult to detect lie of the people. Hence, many companies and law governing office perform polygraph tests. A polygraph test is also known as lie detector. It is used to calculate and record many psychological factors which are caused when a person tells a lie. According to psychologists, a person who speaks a lie, have some psychological and behavioural pattern changes in the body. Few factors such as changes in blood pressure, pulse rate, breathing pattern and skin differences can be observed when a person is questioned. This is how it works and helps in uncovering the truth.

lie detector tests

What is lie detecting test?

It is believed that, when a person lies, the psychological responses can be differentiated from abnormal changes in the body. These can be associated with misleading answers and, hence they can be assessed. The polygraph tests were first invented in 1921 by a medical student John Augustus, in California. He worked along with the police officer in Berkeley Police Department in Berkeley, California. Later this polygraph test was registered as one of the most helpful and popular inventions in Encyclopaedia Britannica in 2003. Since, this test is majorly used by police department; it has been seen as the turning point of investigation.

However, the efficiency of the test is always been a topic of debate. Many scientists have considered it to be counterfeit and termed it as a pseudoscience. Some countries have applied this test in their investigation procedures. They use it as an interrogation tool against people with criminal backgrounds or suspects. Apart from the police force, this testing tool is also applied for the use of employment in certain public or private sector offices. The countries like USA, European countries, Asian countries have applied these tests in their investigative procedures. The polygraph examination is also known as psychological detection of deception. This is popularly known as a lie Detector Test.

Polygraph testing Methods for employment verification and beyond  – Does it really work?

Polygraph testing has been designed to scrutinize physiological or functional response of the people. There are certain computerized evaluation methods, due to which any psychological factor is calculated. The validity of the test is often questioned regarding the relevant and irrelevant testing method. It is often not considered as an ideal testing method. The polygraph testing is the control question method. The investigators of FBI have used it time and again for questioning the suspects and completing the investigations.Polygraph test has been known to be done with the combination of medical devices. When a person is questioned about any certain event or incidents and corresponding changes in the body pattern is calculated.