A New Target for Deep Brain Stimulation (DBS) for Refractory Depression
Deep brain stimulation (DBS) is a treatment for illnesses such as Parkinson’s, chronic pain, and depression. In DBS, electrodes inserted in the brain produce electrical impulses. Different anatomical parts of the brain have been targeted successfully using DBS. These include the subgenual anterior cingulate (Area 25), the nucleus accumbens, and the habenula. Now researcher Thomas E. Schlaepfer has found that inserting the n. accumbens electrode deeper and closer to the ventral tegmental area or the VTA (which contains dopamine cell bodies) produces more rapid onset of antidepressant effects (in a matter of days) in a high percentage of patients (7 out of 8 according to one of Schlaepfer’s reports). Stimulation of the nucleus accumbens in the typical location resulted in 50% improvement in 5 out of 10 patients after one year of follow-up.
Schlaepfer believes that changing the position of the electrode places it in the medial forebrain bundle (MFB), which contains fibers going from the VTA to the nucleus accumbens. Interestingly, when animals are given the opportunity to self-stimulate this area (by pressing a lever that activates an electrode placed in the area), they will, indicating it is rewarding or pleasurable. The same animals will avoid self-stimulating certain other fiber tract sites in the brain.
Schlaepfer’s research was presented at the 2013 meeting of the Society of Biological Psychiatry, and the abstract is available in the Convention Supplement to the journal Biological Psychiatry, Volume 73, Number 9S.
