In a recent sham controlled study with 25 participants, depression patients were given deep brain stimulation (DBS) on their lateral orbitofrontal cortex (lateral OFC), and reported positive changes in mood immediately, compared to sham sessions.
Deep brain stimulation was delivered across a range of different brain regions and subjects generally reported no acute stimulation-induced changes in mood– and even occasionally reported feeling uneasy and other unpleasant symptoms during the sweep of stimulation sessions across multiple brain regions. However, for lateral OFC stimulation with stimulation frequency of 100 Hz, pulse width of 100 microsecond, current amplitude of 1 or 6 mA and duration of 100-200 seconds– subjects reported significant improvements in mood. Mood improvements faded quickly during termination of stimulation.
It is important to note that while DBS and other neuromodulatory interventions are seemingly effective in treating the symptoms of depression, they generally don’t provide a cure for depression. The article ends by bringing to attention the current lack of understanding of the precise mechanisms by which focal brain stimulation actually causes complex behavioral changes through modulating the network activity of the target brain region.
The original journal article is linked below: