Lie detectors, or polygraphs, are often seen as machines that can directly detect dishonesty. In reality, they don’t measure lies at all—they measure physiological responses like heart rate, breathing, blood pressure, and skin conductivity. Because of this, they can sometimes be fooled, misinterpreted, or produce misleading results.

In this episode, we explore how polygraph tests actually work and why they are not foolproof. We dive into psychology, physiology, neuroscience, behavioral science, interrogation techniques, signal interpretation, and forensic engineering. We examine how stress, anxiety, fear, and even calm confidence can all influence the same readings that are supposed to indicate deception.

We also explore why some people can manipulate their physiological responses through controlled breathing, mental distraction, or c ...