Movies like The Shining frighten most of us, but some brain-damaged people feel no fear when they watch a scary film. However, an unseen threat — air with a high level of carbon dioxide — produces a surprising result. Warner Bros./Photofest hide caption

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Chances are they already speak more languages than you: children from Papua New Guinea's Andai tribe of hunter-gatherers wait for their parents to vote in the village of Kaiam. Over 800 languages are spoken in PNG, a country of about six million people. Torsten Blackwood/AFP/Getty Images hide caption

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A visitor to the Wellcome Collection's 2012 exhibition "Brains: The mind as matter" looks at a functional magnetic resonance image (fMRI) showing a human brain as it listens to Stravinsky's "Rite of Spring" and Kant's third Critique. Miguel Medina/AFP/Getty Images hide caption

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The warmer orange colors show parts of the brain most active during improvisational rap. The blue regions are most active when rappers performed a memorized piece. NIDCD hide caption

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Matt Langione, a subject in the study, reads Jane Austen's Mansfield Park. Results from the study suggest that blood flow in the brain differs during leisurely and critical reading activities. L.A. Cicero/Stanford University hide caption

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Researchers are using MRI scans to learn more about the brains of people with extraordinary memory. iStockphoto.com hide caption

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Megan Lutz, left, and Justin Chun react to amateur comedian Robert Lynch at the Metropolitan Room in Manhattan, N.Y. Lynch is an anthropologist researching what laughing reveals about us. Melanie Burford for NPR hide caption

itoggle caption Melanie Burford for NPR

Researchers studying brains want to know what's happening in an area called the premotor cortex — the place in the brain that gears up for something the body is about to do, like swimming. Above, Michael Phelps dives off the starting blocks in the final heat of the men's 400-meter individual medley during the 2012 U.S. Olympic Swimming Team Trials in Omaha, Neb., on June 25. Jamie Squire/Getty Images hide caption

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Unrefrigerated brains in preserving solution are stacked high on shelves at the Harvard Brain Tissue Resource Center at McLean Hospital. Olin College of Engineering/Flickr hide caption

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This image shows the grid structure of the major pathways of the brain. It was created using a scanner that's part of the Human Connectome Project, a five-year effort which is studying and mapping the human brain. MGH-UCLA Human Connectome Project hide caption

itoggle caption MGH-UCLA Human Connectome Project