Shirley Mason was the psychiatric patient whose life was portrayed in the 1973 book Sybil. The book and subsequent film caused an enormous spike in reported cases of multiple personality disorder. Mason later admitted she had faked her multiple personalities.

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Dan Buettner spent years seeking out the happiest populations in the world to try to figure out what characteristics they shared. Tightly knit networks of family and friends were key, he found. In Mexico, for example, Buettner found a "family first" mentality that applied to both immediate and extended family helped Mexicans cope in otherwise stressful circumstances.

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Afghan men wait to receive psychiatric treatment in a Kabul hospital. Scarred by decades of war, social problems and poverty, more than 60 percent of Afghans suffer from stress disorders and mental health problems.

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Language drives Johnson's art since her illness, as depicted in her piece called Enthusiastic, created in 2009.

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Nikki Perez struggled after being diagnosed with mental illness. A course is training her how to help others in crisis.

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A child's room is seen in a destroyed home after the tornado passed through Joplin on May 26. The city's residents are still coping with losses from the storm, which damaged or destroyed an estimated 8,000 structures. Mario Tama/Getty Images hide caption

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Nengah, 35, suffers from schizophrenia. Until recently, her family on Bali in Indonesia kept her chained to a concrete pit for nearly a decade. Cokorda Bagus Jaya Lesmana/Courtesy of GlobalPost hide caption

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