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How Software Changed the Lie Detector Test

Explore the transformative journey of lie detection technology from mechanical marvels to digital accuracy. Delve into the pioneering work of Larson and Keeler, the digital revolution in the 1990s, and the cutting-edge advancements brought by software and AI. Uncover the controversies, the leaders in lie detection software, and the future implications of AI in uncovering deception. A must-read for enthusiasts and professionals in the field of lie detection.

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A Brief History of the Lie Detector Test

From ancient methods to sophisticated technology, the polygraph has evolved significantly. Originating with simple techniques in ancient China, it transformed through pioneers like Mosso, Larson, and Keeler. Today, digital advancements enhance its accuracy, making the polygraph a key tool in truth detection despite debates on its reliability.

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John Larson – The Innovator of Polygraph Science

John A. Larson, a true innovator, developed the world's first accurate lie detector device, laying the foundation for the modern polygraph machine. Larson's interest in deception detection began with the work of William Moulton Marston, where he measured changes in blood pressure, pulse rate, respiration, and electrical skin conductivity. Larson advanced Marston's work, modifying an Erlanger Sphygmomanometer to record changes in blood pressure using a smoked paper drum and a kymograph. Larson published several papers on his instrument, which served as the foundation for Leonard Keeler's advancements in the 1920s and 1930s, earning Larson a spot in history as one of the biggest contributors to the improvement of criminology and criminal interrogation techniques.

John Larson at right demonstrating his "polygraph" lie detector machine at Northwestern University about 1936