Researchers at the Mayo Clinic have set up what they're calling a "living lab" to learn more about the effects of old age. The laboratory is part of the Healthy Aging and Independent Living Initiative, which tests strategies for extending the number of years that seniors live healthy, independent lives. U.S. Census data show that two-thirds of Minnesota counties have populations older than the national average. It is a trend that has broad implications for everything from the state's budget to health care. Molly McMahon, a designer for Mayo Clinic's Center for Innovation, wants to know how aging changes a person's life.