User:Drpartin/sandbox

While taking a polygraph test you wear a blood pressure device to measure your fluctuations, respiration is measured by wearing pneumographs around your chest, and finally electrodes are placed on the subject’s fingers to measure skin conductivity. In order to determine truth it is said the responder will show more signs of fear when answering the control questions over the relevant questions. If a person is showing a deception then there will be changes in then the autonomic arousal responses to the relevant questions, some data is considered inconclusive if there is no fluctuation in any of the questions.

There are many issues with polygraph tests because many people have found ways to try and cheat the system. Some people have been known to take sedatives to reduce anxiety; using antiperspirant to prevent sweating; and positioning pins or biting parts of the mouth after each question to demonstrate a constant physiological response.

"When a person lies, an involuntary interference of the nerves causes the vocal cords to produce a distorted sound wave, namely a frequency level which is different from the one produced by the same person when telling the truth" (Manes, 1998)