The Truth About Lie Detectors
 

*Source: LiveScience (http://www.livescience.com/health/07...ad_lies.html)*
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Good liars have little to lose and everything to gain from taking a "lie detector" test. It's the truthful people who need to worry about polygraphs.

A polygraph not a lie detector; it never was. A polygraph detects physiological expressions associated with lying in some people, such as a racing heart and sweaty fingers. The determination of truth vs. falsehood is a subjective interpretation by the polygraph examiner.

Not surprisingly, the examiner is often wrong.

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