A new type of magnetic stimulation to the brain may improve depression symptoms more efficiently than other treatment options, researchers suggest.

A team at Ghent University in Belgium led by Dr. Chris Baeken and that included 2015 NARSAD Independent Investigator grantee Gilles Pourtois, Ph.D., looked at a type of transcranial magnetic stimulation (TMS)—the application of a magnetic field to the scalp, to stimulate brain cells and so alter circuits involved in depression. The variant of TMS they examined is a sped-up form of intermittent theta-burst stimulation, called iTBS. This method, they propose, has unique treatment potential because it can be applied to the brain for shorter sessions than other forms of stimulation, meaning patients may be able to obtain relief more quickly than with standard antidepression treatments, which can take 6-8 weeks or longer to show benefit (or lack of benefit).When administered over a period of about a week, accelerated iTBS reduced depression symptoms in a significant number of patients, the researchers concluded in a paper published in the Journal of Affective Disorders in April 2016. Symptoms were measured both by psychiatrists and by self-report, among patients who received days of real iTBS treatment as well as a few days of “fake” (i.e., placebo) treatment, for comparison. The fake treatment also relieved some patients’ depression symptoms, the researchers note. The frequent attention that patients receive for iTBS may give it a stronger placebo effect than comparable treatments.

Importantly, the number of patients who improved following the iTBS treatment more than doubled two weeks after the trial ended. This finding fits with other work suggesting that accelerated iTBS changes brain activity by altering processes involved in longer-term memory and storage, giving the treatment delayed effects. Studies more precisely examining brain physiology are needed to investigate this possibility, the researchers say.

Patients reported no serious adverse effects from the treatment, though most of them mentioned short-lived headaches or minor pain at the stimulation sites, particularly at the beginning of their first session.  The researchers are continuing to investigate and analyze the safety profile of iTBS.