Physicians at the University Clinics of Bonn and Cologne have treated ten patients with severe depression with deep brain stimulation.
The method involved implanting electrodes in the patients' nucleus accumbens-a centre in the brain that plays a key role in as the brains reward system, whose function may be impaired in depressive people.
After the treatment, depression improved significantly in half of the patients.
All patients had suffered from very severe depression for many years and did not respond to any other therapies.
The nucleus accumbens ensures that we remember good experiences and puts us in a state of pleasant anticipation.
Without a reward system we would not forge any plans for the future, as we would not be able to enjoy the fruits of these plans. Inactivity and the inability to experience pleasure are two important signs of depression.
A total of ten patients with very severe depression participated in the study.
In all patients, symptoms did not improve despite many therapies using psychotherapy or pharmacotherapy.
Overall, all participants showed signs of improvement, in half of them symptoms of depression improved significantly. Initial effects could sometimes be seen just after a few days.
"Thus, inter alia we observed increasing activity of the patients. This was so successful that some of them were even able to work again, after having been incapacitated for many years. None of our patients had ever responded to any other therapy to a comparable extent before," said Professor Thomas E. Schlaepfer from the Bonn Clinic of Psychiatry and Psychotherapy.
Five patients' well-being improved considerably and in a sustained fashion.
Even after a year, the stimulation of the nucleus accumbens still had the same efficacy as at the beginning of the study.
During the study, the scientists also observed distinct anxiety-relieving effects, which had not been observed in studies on deep brain stimulation to date.
The results of the study are published in the journal Biological Psychiatry.