Polygraphs

Part of speech: noun

Definitions

1. An instrument used to measure and record physiological responses such as heart rate and blood pressure to detect deception
2. A device that assesses multiple bodily functions simultaneously, often employed in lie detection scenarios
3. A machine that captures various physical indicators with the aim of determining truthfulness or stress levels during questioning

Etymology: The word "polygraphs" is simply the plural of "polygraph," so the story belongs to the singular. "Polygraph" is built from "poly-," from Greek "polys," meaning "many," and "-graph," from Greek "graphein," meaning "to write." The name reflects the instrument's original design: it records several physiological signals at once, writing them out together as traces on paper. Those traces are the heart of the device. A polygraph attaches to a person and continuously draws lines tracking changes in heart rate, blood pressure, breathing and skin response, and an examiner reads the pattern of those lines against the person's answers to questions. The idea is that a truthful and an untruthful answer may produce different physical reactions, although the device measures arousal rather than lies directly.

Synonyms: lie detectors, truth machines, deception tests, physiological monitors, biofeedback devices