A lie detector, also known as a polygraph, uses physiological indices blood pressure, pulse, respiration, and skin conductivity during the interview. When the interview is on, some of the reactions represent that the person is lying. This is formed on the hypothesis that if a person is knowingly lying, then it produces some reaction in the person’s body and this is used as an indicator. But the anomaly is that there are no particular physiological reactions that the person may show when the person is lying. More importantly, similar physiological reactions may also occur when a truthful person is afraid to be caught and misunderstood.
Some Facts about Lie Detectors
Sometimes the examiner uses a pretest by going through all the questions before time actual examination, but at times it is a general conversation that the examiner has with the person to be tested with the lie detector. This is done so that the person knows the baseline for the examination and understands what to expect. The examiner also tends to test the machine before starting the actual test by asking very obvious questions like whether the person has ever lied before or not. Continue reading