There is a medication arm and a stimulation arm. Patients will randomized to one or the other. If patients are randomized to the medication arm, after 6 months they have the option of going into the stimulation arm. There is a 3 week trial which includes a crossover period from "no stimulation" to subthreshold stimulation. The 3rd week patients will receive "optimal" stimulation. If they qualify, they will be implanted with the permanent device.