A new study from the Centers for Disease Control and Prevention finds no link between the number of vaccinations a young child receives and the risk of developing autism spectrum disorders. Jeff J. Mitchell/Getty Images hide caption

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People who are socially isolated may be at a greater risk of dying sooner, a British study suggests. But do Facebook friends count? How about texting? iStockphoto.com hide caption

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George McCann has been diagnosed with a subtype of bipolar disorder called the "fear of harm" profile, and finds that a prescribed dose of ketamine every few days alleviates his symptoms. Michael Rubenstein for NPR hide caption

itoggle caption Michael Rubenstein for NPR

Social worker Nuria Casulleres shows a portrait of Audrey Hepburn to elderly men during a memory activity at the Cuidem La Memoria elderly home in Barcelona, Spain, last August. The home specializes in Alzheimer's patients. David Ramos/Getty Images hide caption

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Scientists say that understanding how the cocktail party effect works could help people who have trouble deciphering sounds in a noisy environment. Guests make it look easy at a Dolce and Gabbana Lounge party in London in 2010. Paul Jeffers/AP hide caption

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Despite public health campaigns urging women in the U.S. to take folic acid, many are still not taking the supplements when they become pregnant. iStockphoto.com hide caption

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State Senator Jeff Klein (L-R), Assembly Speaker Sheldon Silver, Lieutenant Governor Robert Duffy and Senator Andrea Stewart-Cousins congratulate New York Governor Andrew Cuomo after he signed the New York Secure Ammunition and Firearms Enforcement Act on Tuesday. Hans Pennink/Reuters/Landov hide caption

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If you know some mice that took This Is Spinal Tap too literally, they might want to know about an experiment to restore hearing with a failed Alzheimer's drug. The Kobal Collection hide caption

itoggle caption The Kobal Collection

This satellite image from Oct. 28 shows Hurricane Sandy in the Atlantic Ocean before making landfall. NASA via Getty Images hide caption

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Brain scans using Amyvid dye to highlight beta-amyloid plaques in the brain. Clockwise from top left: a cognitively normal subject; an amyloid-positive patient with Alzheimer's disease; a patient with mild cognitive impairment who progressed to dementia during a study; and a patient with mild cognitive impairment. Slide courtesy of the journal Neurology hide caption

itoggle caption Slide courtesy of the journal Neurology

A person's DNA can say a lot about a person, but not why someone has committed a horrific crime like mass murder. iStockphoto.com hide caption

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A boy in Lima, Peru, receives a hepatitis B vaccine during an immunization drive in 2008. The United Nations is considering a ban on the preservative thimerosal, which is often used in hepatitis B and other vaccines in developing countries. Martin Mejia/AP hide caption

itoggle caption Martin Mejia/AP

A light micrograph image of telomeres, shown in yellow, at the end of human chromosomes. Women tend to have longer telomeres than men and tend to outlive men, according to new research matching genetic information with medical records. Peter Lansdorp/Visuals Unlimited/Corbis hide caption

itoggle caption Peter Lansdorp/Visuals Unlimited/Corbis