Polygraph (redirected from Polygraph examination)

lie detector

 or polygraph

Instrument for recording physiological phenomena (including blood pressure, pulse rate, and respiration) of a human subject as he or she answers questions asked by an operator. These data (recorded as graphs) are used as the basis for judging whether the subject is lying. The phenomena usually chosen for recording are those not easily controlled voluntarily. The types of questions asked, their wording, and the mode of presentation have a tremendous effect on the results and their reliability. Used in police interrogation and investigation since 1924, the lie detector is still controversial among psychologists and not always accepted as evidence in courts.

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polygraph

an instrument for the simultaneous electrical or mechanical recording of several involuntary physiological activities, including blood pressure, skin resistivity, pulse rate, respiration, and sweating, used esp as a would-be lie detector

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polygraph [′päl·i‚graf]

(engineering)

lie detector

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Polygraph 

a multichanneled oscillograph for simultaneously recording readings of several physiological functions, such as respiration, blood pressure, brain and muscle bioelectricity, and motor reactions. The most common type is the general-purpose polygraph, a multichanneled oscillograph that records with ink various bioelectric and nonelectric processes by means of appropriate biological sensors and adapters. The polygraph is used in physiological experiments to investigate interacting and interdependent bodily functions; it is also used in clinical diagnosis.