Stimulating the brain with a weak electric current is an effective treatment for depression and could have other health benefits, according to researchers in Australia. About half of the depressed people studied had substantial improvements after Transcranial direct current stimulation (tDCS), while other participants said the treatment improved their concentration and eliminated chronic pain.
Transcranial direct current stimulation passes a weak depolarizing electrical current into the front of the brain through electrodes on the scalp. Patients remain awake and alert during the procedure.
“We are excited about these results. This is the largest randomized controlled trial of transcranial direct current stimulation ever undertaken and, while the results need to be replicated, they confirm previous reports of significant antidepressant effects,” said Professor Colleen Loo of the University of New South Wales’ School of Psychiatry. “Most of the people who went into this trial had tried at least two other antidepressant treatments and got nowhere. So the results are far more significant than they might initially appear. We weren’t dealing with people who were easy to treat.”
In the study, 64 depressed participants received tDCS therapy for 20 minutes every day for up to six weeks or were part of a control group. Participants who improved during the trial were offered weekly booster treatments, with about 85% showing no relapse after three months.
“These results demonstrate that multiple tDCS sessions are safe and not associated with any adverse cognitive outcomes over time,” said Loo, who adds that tDCS is simple and inexpensive, requiring only a short visit to a clinic.
Transcranial direct current stimulation is different from Electroshock Therapy (ECT), a controversial treatment for mental illness that uses stronger electric currents.
The tDCS study also found unexpected physical and mental benefits, including improved attention and information processing. One participant with chronic neck pain reported the pain disappeared during the trial. “We think that is because tDCS actually changes the brain’s perception of pain,” Loo explained. “We believe these cognitive benefits are another positive aspect of the treatment worthy of investigation.”
The researchers are now looking at an additional trial that would include people with bipolar disorder. Previous research indicates tDCS is effective at treating Parkinson’s disease, fibromyalgia, stroke and chronic pain.
The study is being published in the British Journal of Psychiatry.