How Does A Polygraph Test Work?

In this video excerpt from NOVA scienceNOW, learn about polygraph tests and lie detection. Correspondent and New York Times technology columnist David Pogue commits a staged crime and undergoes a polygraph test to find out how it works. Lying can cause stress, which produces common physiological responses, such as an increased heart rate and sweating. Polygraph testing experts explain what the test measures, why the questions are reviewed in advance, and why the test doesn't always work. This video is available in both English and Spanish audio, along with corresponding closed captions. CREDITS: LICENSE:

LicenseCustom License

More videos by this producer

The Coriolis Effect Due to Earth's Rotation

Learn how Earth’s rotation causes the Coriolis effect, with this video from NOVA. Use this resource to visualize the abstract concept of the Coriolis effect and to provide opportunities for students to use evidence to support a claim about the influence of the Coriolis effect on hurricanes, jet stre

Personal DNA Testing

In this video from NOVA scienceNOW, take a behind-the-scenes look at the process of personal DNA testing, and hear more about the innovative Personal Genome Project. CREDITS: LICENSE:

How DNA Replicates

This narrated animation from Interactive NOVA: "The Secret of Life" shows the double helix structure of DNA and how the molecule replicates. The segment illustrates how DNA "unzips" to form templates for the new strands and how complementary nucleotides bind together like the rungs of a ladder. This