Some patients with depression are helped by therapy, or drugs, or, more often, a combination of the two. But for others, nothing medicine has been able to offer could soften the blackness and bleakness of the illness. Helen Mayberg is working hard to change that, using a technique called deep-brain stimulation, in which electrodes are inserted deep into the cortex of patients with unremitting depression. And although she’s treated only a small number of patients so far, she’s had some spectacular successes. She will update us on the latest studies, including work on the identification of markers seen during neuroimaging that can predict which treatment is best for an individual patient and how that patient is likely to respond. Her work is unique in both illuminating the causes of depression and providing immediate clues to treatment.