Alzheimer's disease has been described as health care's “ticking time bomb.” The degenerative disease slowly destroys the brain's ability to remember, reason or control simple bodily functions like swallowing food. While scientists have found compelling evidence suggesting possible causes, they still don't have a cure or a generally accepted way to screen for the disease. With the number of Americans age 65 and over expected to more than double by 2030, health-care experts are bracing for a surge of new cases that could devastate families psychologically and economically and strain the nation's health-care system. Researchers are hoping a series of new treatments may delay the onset of symptoms. But some experts say progress hinges on Congress providing more research funding.