A D.C. doctor blogs about his decline as Alzheimer's claims his mind "Yes," the chaplain told him, "I remember you from last time." Hilfiker had driven to the Buckingham Correctional Center in Dillwyn, Va., just a few months earlier. There, he had sat in the same visitor's room with the same friend for four hours. Hilfiker remembered none of it. At the time, he dismissed the incident as a bizarre memory lapse, perhaps a byproduct of his age, then 66. But now, two and a half years later, he recognizes it for what it was: one of the first major signs of his mind's decline. Hilfiker has Alzheimer's, a brain disease expected to afflict a record 14 million Americans by 2050, inflicting a terrible emotional and economic toll on communities, families, and the men and women who learn that their memories and identities will slowly be lost. For Hilfiker, a family doctor who has spent decades helping the District's most vulnerable, that moment came six months ago. Since then, he has grappled with how to tell those around him, when to let go of responsibilities and, as a man who has always defined himself by his mind, who he will be when it's gone. He has also taken the unusual step of chronicling his demise in a blog titled "Watching the Lights Go Out," providing a sobering guide for the millions headed behind him into the darkness. "I'm facing the collapse of so much of what has given me meaning," he wrote in one of his early posts. What is it actually going to be like? Three decades ago, Hilfiker stepped into an exam room and found a worried man and his wife waiting for him. "Something's wrong with Mama," the man said. A quick look at Mama revealed that her mind had been slipping away long before her husband had sought help. We humans have amazing denial mechanisms, of course, but why are they almost universally so powerful in dementia? Hilfiker blogged. It's shame and fear, I suspect; shame so strong that one can't bear to entertain the possibility and fear of isolation so overwhelming that telling others . . . terrifies us. In many ways, Hilfiker's entire life has prepared him to write with ease and expertise about an illness that would leave most people besieged and lost. He has never been an emotional person. When he found out that his mother committed suicide his sophomore year of college, he cried for two minutes. Years later he pieced together her long struggle with depression, but it would take him years more to recognize that he shared her illness.