⏰ when
When was the first reliable human lie detection polygraph developed?
Quick Answer
Early polygraph devices appeared in the 1920s. John A. Larson’s version was developed in 1921.
The Full Story
The modern polygraph traces back to 1921, when John A. Larson developed an early device to record breathing, pulse, and blood pressure during questioning. The polygraph was intended to detect physiological signs of deception, though its accuracy has always been debated. Over time it became used in law enforcement and security settings, but it is not considered a perfect lie detector. Its history reflects the long search for a direct measure of truthfulness from the body and brain.
Key Facts
1.Early polygraph developed in 1921
2.John A. Larson built an influential version
3.Polygraph accuracy remains controversial
YouTube Angle
Suggested video title for this topic:
"Can a machine really tell when someone is lying?"
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