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What Is a Lie Detector Test?

In an effort to determine if an individual is being honest, he or she can undergo a lie detector test. Such a test involves measuring the individual’s response to questions posed by an examiner. The answers provided are measured by physiological responses and are later evaluated and analyzed by a professional.

Also called a polygraph test, a lie detector test is usually done during a criminal investigation. The defendant in a court case or a relevant witness may be subject to a lie detector test to prove that he or she is stating only the truth. Multiple sensors are attached to the subject of a lie detector test in order to record any physiological responses the subject may make in answering a question. Such physiological responses include heart rate, perspiration, blood pressure, and respiration. It has been previously proven that an individual who is lying usually has an increase in heart rate as well as an increase in blood pressure. The subject also perspires excessively as well.

However, a lie detector test is not entirely accurate in determining if a response from the subject is a false statement or not. Some circumstances lead to errors such as a subject suffering from anxiety. It is also possible for the subject of a lie detector test to manipulate the results or the physiological responses he or she makes through sedatives and other chemical inducements. Despite these problems, lie detector tests are still used by law enforcement agencies in order to evaluate and question suspected criminals or witnesses.

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