New studies have showed "brain pacemaker" can effectively treat depression and obsessive-compulsive disorder (OCD), media reported on Tuesday.

Devices implanted in the chest, with leads that send electrical impulses to parts of the brain, have already been approved to treat movement disorders, such as Parkinson's disease, essential tremor and dystonia.

Dr. Ali Reza who led the studies said the technique of deep brain stimulation (DBS) helped the most severely depressed patients improve significantly.

Six of 17 severely depressed patients were in remission a year after undergoing DBS and four more markedly improved, and more than half of 26 obsessive-compulsive patients showed substantial improvement over three years, say studies from a team at the Cleveland Clinic, Brown University, and Belgium's University of Leuven.

"Not all patients get better, but when patients respond, it's significant," said Helen Mayberg, who has implanted about 50 depression patients.

Her first remains in remission after five years; she estimates that four of every six show enough improvement to be classified as "responders."

(Agencies via Xinhua News Agency May 27, 2008)