Polygraph, Risk Management & Investigations
PAV Polygraph Services

History of polygraph

The term "polygraph" literally means "many writings". The name refers to the manner in which selected physiological activities are simultaneously recorded.The attempt to detect deception is as old as mankind itself. Since time in history, different methods have been utilized to detect deception, for example pulse-taking by the Greeks in 300BC, or the swallowing of a rice cake in China in 220BC.
 In modern times, more scientific methods have been developed to uncover deception.

The first person to utilize an instrument for the purpose of detecting lies was C Lombroso in 1895. He measured changes in blood pressure and pulse rate with a hydrosphygmograph.   J Larson (1921) was the first person to use a continuous method of recording changes in blood pressure and pulse rate and more than one recording to detect deception. In 1926,    L Keeler developed a more complex recording instrument, utilizing blood pressure changes, pulse rate and respiration. He added the galvanograph in 1936. The first electronic polygraph was introduced in 1974 by Stoelting Co.

Today most examiners use computerized polygraph instruments.