Which instrument is commonly used to assess truthfulness by recording physiological responses?

Which instrument is commonly used to assess truthfulness by recording physiological responses?

• A. Polygraph
• B. EEG Monitor
• C. MRI Scanner
• D. GSR Meter

Answer: (A)

Recording physiological responses to gauge truthfulness relies on the idea that deception can trigger measurable arousal. A polygraph is designed to capture several signals at once—breathing patterns, heart rate, blood pressure, and skin conductance. By comparing these responses during relevant questions to those during control questions, patterns are sought that might indicate deception. This multi-signal approach is why the polygraph is the instrument most commonly associated with lie detection. In contrast, an EEG monitor looks at brain electrical activity, an MRI scans brain structure and function, and a GSR meter measures skin conductance alone, which is only one part of what the polygraph assesses. Because deception can influence several bodily systems and the polygraph combines these signals, it remains the best-fitting choice for this purpose.

Recording physiological responses to gauge truthfulness relies on the idea that deception can trigger measurable arousal. A polygraph is designed to capture several signals at once—breathing patterns, heart rate, blood pressure, and skin conductance. By comparing these responses during relevant questions to those during control questions, patterns are sought that might indicate deception. This multi-signal approach is why the polygraph is the instrument most commonly associated with lie detection. In contrast, an EEG monitor looks at brain electrical activity, an MRI scans brain structure and function, and a GSR meter measures skin conductance alone, which is only one part of what the polygraph assesses. Because deception can influence several bodily systems and the polygraph combines these signals, it remains the best-fitting choice for this purpose.