Brain rewiring

Using magnetic fields to treat depression is gaining favour

Brain rewiring

Lying back in a spacious, pleather armchair, Barbara Kwasniewski seems relaxed, especially given the nature of the medical treatment she’s just received. The 53-year-old has undergone repetitive transcranial magnetic stimulation (rTMS), which essentially rearranges the pathways of the brain by using magnets.

The therapy was approved by Health Canada in 1997, and by the U.S. Food and Drug Administration in 2008. It’s used to treat everything from strokes to depression, anorexia, migraines, obsessive-compulsive disorder, chronic pain and Parkinson’s. It’s one of a handful of therapies gaining popularity that use electricity to help rewire the brain. Deep brain stimulation is another, where wires are surgically implanted into a patient’s grey matter to excite the neurons with electronic pulses. Electro-shock therapy has also made a comeback.

Of these electrical brain therapies, rTMS is the least invasive. Research is under way to determine its full potential: doctors aren’t sure whether it’s better to target one or both sides of the brain. They now stimulate just one side—the region depends on the disease—but this may change with further research. Nor have they determined how intense to make the magnetic field. If it’s too strong, there is risk of causing a seizure. But if it’s too weak, the treatment won’t work. For these reasons, the therapy is regarded as experimental, says Dr. Gary Hasey, who started the first therapeutic transcranial magnetic stimulation lab in Canada in 1997.

What’s groundbreaking about the treatment is that it can help people for whom all other options have failed. Studies show that about 40 per cent of these people improve, says Dr. Jeff Daskalakis, a psychiatrist who runs the brain treatment and research program at the University of Toronto. Kwasniewski fell into a deep depression 13 years ago, after giving birth to her daughter. She slept 18 or 20 hours per day. She tried every “antidepressant under the sun.” Suicide was never far from her mind, and she would probably have gone through with it, she says, but for her daughter.

For the past three years, Kwasniewski has come to the Toronto-based Centre for Addiction and Mental Health (CAMH) for 20-minute sessions of rTMS. Twice a week, she sits in the big armchair. Next to the chair is a box with dials and knobs. Connected to the box is a black wire coil shaped like a figure eight. A nurse holds the coil to the top of Kwasniewski’s head, just above the dorsolateral prefrontal cortex—an area of the brain responsible for planning and organization. When a current goes through the wire, it sets up a magnetic field, which is strongest at the point where the wires cross. The magnetic field excites the neurons underneath the coil, activating the pathways of her brain that inhibit negative thinking. The wire makes a clicking noise that sounds and feels, she says, like a woodpecker tapping at her skull. The known side effects of the treatment are seizures, headaches and involuntary clenching of facial muscles, but so far, she’s only suffered slight head pain after an early treatment.

In the public system, rTMS is available in Toronto, Hamilton, Vancouver and Red Deer, but growing demand means the queues can be long; for example, at Toronto’s CAMH, the wait is one year. The MindCare Centres offer the country’s only private rTMS program, with clinics in Vancouver, Toronto and Ottawa. A Montreal clinic opened just last week, and there’s one more slated for Toronto. The cost is $5,000 to $7,500 for a course of treatment that lasts two to three weeks. The fees can be covered under insurance, although it’s decided on a case-by-case basis. MindCare uses particularly strong magnets, setting the frequency above what has been tried in the research studies, and they report a higher success rate, with about 60 per cent of patients improving.

Every four months Bill Neill, 53, who lives in Oakbank, a suburb of Winnipeg, flies to Vancouver for a week of rTMS treatment at a MindCare Centre, which costs about $8,400 per year, including flights and hotels. Neill’s doctors suggested he try rTMS because none of the anti-depressants eliminated his seasonal depression that was so serious that he used to take a leave from his job with Manitoba Hydro for a few months every year, and spend his days curled up in a ball, crying. He will probably need magnet therapy for the rest of his life, he says. “The cost is a stretch,” says the father of three. “But it means I no longer live my life on a roller coaster.” For Kwasniewski, the therapy has boosted her confidence and given her a renewed sense of purpose: her weight has fallen by 100 lb., and she has started to socialize again. Although there aren’t any studies on how the therapy will affect her long-term health, she doesn’t care. “If my brain turns to jelly in 20 years,” she says partly in jest, “at least I will have had all those good years.”

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