Essay On Polygraph Tests

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How Accurate are Lie Detectors (aka Polygraph Tests)?

To determine whether a person is saying the truth or a lie was a goal of mankind for centuries. The methods of Lie Detectors aka Polygraph Test use physiological activity of the individual’s sympathetic nervous system to detect deception by measuring changes of a sympathetic nervous system response.
In ancient China rice was used as a “Lie Detector” where a suspect had to fill his/her mouth with a dry rice and listen to a prosecutor. The purpose of this method was to detect deception, as an anxious person doesn’t salivate, therefore if the suspects didn’t salivate and the rice was dry at the end of the speech the person was found guilty.
I have always questioned the accuracy of the Lie Detectors. Are they really work or it is more of a pseudoscience. Why are Lie Detectors accurate, but not foolproof? How accurate are Lie Detectors (aka Polygraph Tests)?
I will examine the hypothesis that Lie detectors aka Polygraph tests would be the most accurate if verbal and nonverbal deceptive behavior were taken as indications of deception and the lies and truths are classified correctly.
Polygraph “many writings” is referred to a lie detector and it’s the most common method used to detect deception.
However, Lie Detector aka Polygraph Test has many advantages and disadvantages. One of the disadvantages could be a failure of the polygraph examiner properly establish a psychological set and preparation of the examinee to respond to specific questions which

Increase the arousal of the sympathetic nervous system that could lead to deceptive response and examiner’s misinterpretation of data on the polygraph graphs. Another great example when a polygraph examiner or observe...

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...ntain. For example: when deceiver forgets what she/he said at one point and contradicts him/herself on another occasion, or a polygraphist can play a “deceiver” by convincing an examinee in “seeing” a lie on the polygraph’s graph. The last might sound unethical, but it can help to reveal important information such as truth and confession. However, the issue with this approach to unfounded accusatory questions could be stressful for examinee and lead to a false positive.
Although the idea of a polygraph testing is comforting, the practical advice would still remain skeptical for the end results of the lie detector aka polygraph test. .
Advocates of Lie-detector aka Polygraph tests predict that a technological advances will improve accuracy of Lie detectors aka Polygraph tests and the results of the tests will be admissible in the courts as evidence.

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