An unexpected cure: deep brain stimulation. Here is how it works. After twenty years of hardcore drug addiction, Gerod Buckhalter had just two options left: die another casualty of America's drug epidemic, or let a surgeon insert electrodes into his brain. He has now been sober for more than 600 days. Lenny Bernstein reflects on how his success shows what may be possible — but also warns of the psychological, social and socioeconomic factors that complicate the disease.