Alzheimer's is a disease of the brain that causes a loss in memory. This results in dementia, loss of brain functions (thinking, remembering, and reasoning) severe enough to interfere with everyday life. When German physician, Alois Alzheimer, first described the disease in 1907, it was thought to be rare. Today, Alzheimer's disease is the most common cause of dementia, affecting 10% of people 65 years old, and nearly 50% of those age 85 or older. An estimated four million Americans have Alzheimer's. Alzheimer's disease usually begins gradually, causing a person to forget recent events and to have difficulty performing familiar tasks. How quickly the disea...