CNN reports on treating severe depression with electrodes inside the brain:
The procedure -- called deep brain stimulation, or DBS -- targets a small brain structure known as Area 25, the "ringleader" for the brain circuits that control our moods.
Area 25 is relatively overactive in depressed patients. One hypothesis is that in patients who do not improve with treatments for depression, Area 25 is somehow stuck in overdrive.
DBS had been used since 1997 as a treatment for movement disorders, including essential tremor, Parkinson's disease and dystonia.
Treating depression with electrodes inside the brain. CNN, 2012.