A small-scale study of ten patients by researchers at the University Clinics of Bonn and Cologne has shown some promising results for the use of deep-brain stimulation (DBS) for people with severe depression. The participants in the study had all suffered from severe depression for a number of years and had not been helped by drugs or psychotherapy. The DBS involved using an electric current to stimulate a part of the brain called the nucleus accumbens - an important part of the brain's reward system involved in remembering and anticipating good experiences. People with depression often remember only bad things from the past and see little hope for the future so it was hoped that stimulating these parts of the brain would help to overcome this. Five of the participants' well-being improved significantly over a sustained period and even after a year the stimulation of the nucleus accumbens was still as effective. Anxiety also improved, overall brain function was not affected and there were only minor side effects of the treatment but a lot more work needs to be done before DBS can become an established treatment.
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