पॉलीग्राफ

Also known as lie detector, lie detector test

thumb|American inventor Leonarde Keeler testing his improved polygraph on [[Arthur Koehler, a former witness for the prosecution at the 1935 trial of Richard Hauptmann]] A polygraph, often incorrectly referred to as a lie detector test, is a pseudoscientific device or procedure that measures and records several physiological indicators such as blood pressure, pulse, respiration, and skin conductivity while a person is asked and answers a series of questions. The belief underpinning the use of the polygraph is that deceptive answers will produce physiological responses that can be differentiate