Toronto: Canadian researchers claim to have successfully used an electrical surgical technique to relieve severe mental depression in chronic cases.

A team of researchers at Toronto Western Hospital subjected 20 patients with severe depression to what they call deep brain stimulation (DBS). The technique involved using electrical current to relieve depression.

By planting electrodes on the brain of these patients, the researchers passed current through them to jolt an area known as the sub-callosal cingulated gyrus (SCG) in the brain. In the brains of those suffering from Major Depressant Disorder, the SCG has been found to be overactive.

The researchers found that deep brain stimulation (DBS), induced by the electrical current, relieved symptoms of depression in 60 per cent of their patients. One month after the DBS, when these patients were subjected to depression tests, 35 per cent showed reduction in their depression symptoms.

But six months after the DBS, 60 per cent of them showed reduction in their depression symptoms even as 35 per cent suffered remission of symptoms.

The researchers found that patients on the mend showed marked improvement in their sleep and mood patterns. Their appetite also returned as their anxiety symptoms eased.

The findings, published in the current issue of online journal Biological Psychiatry, estimate that 10 to 20 per cent of people suffer from Major Depressant Disorder.

Research shows that while some people are born with this disorder (caused by heightened brain activity or the SCG condition), others develop it later in life.

The new deep brain stimulation (DBS) surgical technique offers fresh hope for patients with Major Depressant Disorder as conventional medical and psychiatric treatment has failed to relieve their symptoms.

The Toronto hospital will continue its research in this area to know why some patients don't respond to the electrical surgical treatment. IANS