Staci Moritz and her son Aidan, 11, play at a park in their neighborhood in Portland, Ore. Caring for three children and her injured husband exacerbated her health problems. Beth Nakamura for NPR hide caption

itoggle caption Beth Nakamura for NPR

Colleen Frainey, 16, of Tualatin, Ore., cut back on advanced placement classes in her junior year because the stress was making her physically ill. Toni Greaves for NPR hide caption

itoggle caption Toni Greaves for NPR

Stressed out? Who isn't? Stress can cause physical changes in the brain that may be linked to Alzheimer's. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Researchers tested the antidepressant Lexapro, or escitalopram generically, to see if it would protect the heart against mental stress. Joe Raedle/Getty Images hide caption

itoggle caption Joe Raedle/Getty Images

Though scientists have identified sleepwalking triggers, the condition is still a bit of a mystery. Victoria Alexandrova/iStockphoto.com hide caption

itoggle caption Victoria Alexandrova/iStockphoto.com

As Xtranormal advertises on its site, "If you can type, you can make a movie." fishbrain.randy@sbcglobal.net/Flickr hide caption

itoggle caption fishbrain.randy@sbcglobal.net/Flickr