received maintenance TMS were significantly less likely to relapse
than those who did not receive boosters (Journal of Affective
Disorders, 2013). But the study was small, and the best way to
administer such treatments is far from settled. “The protocols for
maintenance boosters don’t exist. Nothing has been approved by
the FDA, so we devise our own protocols,” Pandurangi says.
In fact, he adds, when it comes to TMS, “almost everything
is a question.” What’s the best frequency and intensity of the
magnetic pulse? How many total treatments should patients
receive, over how many days or weeks? Where on the scalp
should the current be directed?
Researchers are a long way from fine-tuning the technique,
George agrees. “All the things we did in the first studies used
a good first approximation, and it turned out that it worked,”
he says. “However, it would be inconceivable that the first
approximations were also the best approximations.”
There’s some evidence the total amount of brain stimulation
is what matters, rather than the number of calendar days
spent in treatment, George says. In a recent pilot study, George
and his colleagues tested TMS as a treatment for patients
hospitalized during a suicidal crisis. Patients received nine TMS
treatments in just three days. They experienced no serious side
effects from the rapid-fire course of treatment, George says,
and those who received TMS showed more improvements on
the first day than did control subjects who received a sham
treatment (Brain Stimulation, 2014).
“They got unsuicidal very quickly,” George says — though
he acknowledges that more research and larger samples are
required to fully test the approach.
While many questions remain, scientists who study the
device say it’s a valuable tool for psychologists to keep in mind
when referring patients with difficult-to-treat depression.
“Psychologists should know it’s a good treatment option for
patients who have failed to respond to or tolerate antidepressant
medication,” Schabbing says.
Fire together, wire together
As magnetic brain stimulation continues to be tested in the
real world, researchers are considering whether to expand its
use. Psychotherapy and antidepressants are highly effective
treatments for many people with depression. They’re also more
convenient and less expensive, so TMS is unlikely to become
a first-line therapy for depression that responds to other
treatment. But it has potential for treating other conditions.
Researchers have found that TMS could be effective in
treating vascular depression following stroke, for example
(Archives of General Psychiatry, 2008). Others are studying TMS
as a possible treatment for disorders including schizophrenia,
attention deficit-hyperactivity disorder and post-traumatic
stress disorder. “Following the success with depression, almost
everybody who treats brain diseases is thinking about whether
you could use TMS,” George says.
So far, however, the results are mixed. “The one exception
is in the treatment of pain,” George says. Data suggests TMS
could be helpful in treating both acute pain and chronic pain
conditions such as fibromyalgia — but to date, no companies
have sought FDA approval for that use, he adds.
Meanwhile, scientists are also exploring how to engage
patients in order to maximize the effectiveness of TMS during
treatment for depression. “There’s a concept that says ‘neurons
that fire together wire together,’” says George. According to this
theory, brain cells might be more receptive to treatments when
they’re actively engaged in some task.
For instance, preliminary research suggests patients might
experience greater improvements if they receive TMS while
simultaneously undergoing cognitive-behavioral therapy,
George says. If this line of research pans out, psychologists
could play an important role by providing psychosocial therapy
while patients are in the TMS chair.
And TMS may be just the beginning. Scientists are exploring
other methods of stimulating the brain, including pulsed
ultrasound and optogenetic stimulation. The research could
open up important new avenues for treating mood disorders
and mental illness, Pandurangi says. “It’s exciting to see what’s
coming next.” n
Kirsten Weir is a journalist in Minneapolis.
• George, M. S., Taylor, J. J., and Short, E. B. (2013).
The expanding evidence base for r TMS treatment of
depression. Current Opinions in Psychiatry 26( 1), 13–18.
• George, M. S., Lisanby, S. H., Avery, D., McDonald,
W. M., Durkalski, V., Pavlicova, M., et. al. (2010). Daily
left prefrontal transcranial magnetic stimulation therapy
for major depressive disorder: A sham-controlled
randomized trial. Archives of General Psychiatry 67( 5),
• Slotema, C. W., Blom, J. D., Hoek, H. W., and
Sommer, I. E. C. (2010). Should we expand the toolbox
of psychiatric treatment methods to include repetitive
transcranial magnetic stimulation (r TMS)? A meta-analysis of the efficacy of r TMS in psychiatric disorders.
Journal of Clinical Psychiatry 71( 7), 873–884.