What does a polygraph test measure?

Answer Polygraph tests measure the body's physiological reactions to certain questions, according to the Skeptic's Dictionary. Theoretically, since people tend to get nervous when lying, you can tell if s... Read More »

Top Q&A For: What does a polygraph test measure

What does the polygraph test check for?

A polygraph test is meant to determine whether or not a person is being truthful. Sometimes called a lie detector test, the polygraph measures changes respiration, heart rate and sweat gland activi... Read More »

Who invented the polygraph test?

The polygraph machine was developed in 1921 by psychiatrist Dr. John A. Larson. Larson's machine was the first to measure blood pressure, respiration and pulse. The same year, Dr. Leonard Keeler,... Read More »

Reasons for Taking a Polygraph Test?

Over time, the polygraph test has lost its value in the American legal system. In fact, the polygraph test has always been a device that was almost entirely unique to the American justice system. N... Read More »

How to Cheat a Polygraph Test (Lie Detector)?

A U.S. patent sketch of a polygraph machine at work. The needles chart physiological changes, such as breathing and heart rate, over time. While this sort of machine is still frequently used, compu... Read More »