Deep Brain Stimulation Tested On Bipolar Subjects Unresponsive To Other Treatments
Deep brain stimulation, or DBS, is in its early experimental stages; this study, for example, had only 17 subjects. But when you cut into a person's skull and implant electrodes on either side of the brain while people are awake, it's probably not that easy to attract willing subjects. Nevertheless...
Dr. Helen Mayberg, professor of psychiatry and neurology at Emory University School of Medicine in Atlanta, and her colleagues, achieved successful remission in half of the subjects in her latest DBS study after two years of continuous stimulation. Improvements were also observed in other study participants.
Dr. Mayberg, who pioneered earlier DBS studies with Canadian researchers, was among the first to demonstrate DBS success for patients with depression who were previously resistent to drug treatments and even shock therapy. In the current study, her subjects were patients aged 18 to 70 diagnosed with bipolar disorder, or manic depression; they suffered, unrelieved from depression for four years or longer.
Mayberg, who has been studying depression since the 1980's works from brain scans. She noticed a pattern of brain changes that occured with recovery from depression, whether it was recovery from an anti-depressant drug or from a placebo that a subject believed was a drug. These patterns of activity in the brain occurred in an area of the brain known as Area 25.
The current study centered on changes to Area 25 brought about by DMS stimulation conducted by electrodes periodically delievered to the patient's brains for up to two years by an implanted device akin to a pacemaker. Patient responses grew more positive over time, measured at 6 months, one year, and two years, when 52 percent of the patients experiencde remission of their depressive symptoms and 92 percent demonstrated clinical response.
Mayberg told the Montreal Gazette that DBS doesn't make people happy. Instead "we seem to be removing that deep, dark negative empty sadness - that interference that is so profound that it totally hijacks your brain from doing anything else."
The full study is available online in the January 2, 2012 edition of the Archives of General Psychiatry.