Electrodes placed deep in the brains of severely depressed patients alleviate their misery when no other treatments can, according to new research.
Deep brain stimulation is a relatively new approach to treating brain disease. Unlike electroconvulsive or "shock" therapy, which involves placing electrodes on the scalp, deep brain stimulation delivers small jolts of electricity directly to specific parts of the brain. The technique has been used with some success to alleviate the symptoms of Parkinson's disease, but no one had tried it for depression.
Researchers led by Helen Mayberg of the Emory University School of Medicine in Atlanta, Georgia, targeted the subgenual cingulate, a part of the emotional brain that has been shown to be hyperactive in depression. The team implanted electrodes in the brains of six patients, all of whom had failed to benefit from a variety of therapies, including shock treatments. The electrodes were attached to generators implanted under their collarbones that continuously delivered high-frequency, low-voltage pulses of electricity.
All patients experienced immediate effects from the stimulation--reporting such impressions as a "disappearance of the void" and feelings of "connectedness." After 6 months with the implants, four of the six said their depression had mostly lifted. In one woman, the experimenters tried turning off the stimulator and found that depressive symptoms gradually returned after a few weeks. But she cheered up soon after the current was turned on again, the scientists report today in Neuron. Mayberg believes that the longer the treatment period, the more durable the effects will be.
The technique "has a lot of potential" particularly for treating "refractory" patients, says Husseini Manji, a psychiatrist at the National Institute of Mental Health. "It also may be useful in helping us understand the circuitry involved in severe mood disorders."