Treatment of severe depression with magnetic stimulation is moving beyond large mental health centers and into private practices nationwide, following more than two decades of research on the treatment. Yet even as concern about its efficacy fades, one potential side effect—seizures—continues to shadow the technology.

Called repetitive transcranial magnetic stimulation (rTMS), the noninvasive technique uses electromagnets to create localized electrical currents in the brain. The gentle jolts activate certain neurons, reducing symptoms in some patients. Eight psychiatrists contacted for this article, all of whom use rTMS to treat depression, say it is the most significant development in the field since the advent of antidepressant medications. The prevailing theory is that people with depression do not produce enough of certain neurotransmitters, which include serotonin and dopamine. Electricity (administered in combination with antidepressants) stimulates production of those neurotransmitters.

Scope of the problem
A National Institute of Mental Health (NIMH) study released this spring shows that 14 percent of patients with drug-resistant major depressive disorder experience a remission of symptoms after rTMS treatment compared with a control group, which reported a 5 percent rate of remission. Physicians and researchers say those results are similar to the success rate of antidepressants. No notable side effects occurred during the study, according to its authors, who include Mark George, an early rTMS researcher and a professor of psychiatry, radiology and neurosciences at the Medical University of South Carolina in Charleston. They have suggested that higher levels of electrical stimulation might attain better results.

At the heart of this interest in rTMS treatment is the only such device cleared by the U.S. Food and Drug Administration (FDA). In October 2008 the government specified that Neuronetics, Inc.'s NeuroStar could be used to treat major depressive disorder that is resistant to at least one antidepressant medication. Since then, about 200 centers and clinics in the U.S. have purchased the $60,000 system, which resembles a contemporary dentist's chair with an electronics console.

The treatment joins talk, pharmaceutical and electroconvulsive therapies (the latter of which rTMS is an offshoot) as the only known methods of alleviating the debilitating symptoms of depression. Nearly 7 percent of U.S. adults, or 14.8 million people (predominantly women), are afflicted by major depressive disorder each year, according to the NIMH. In fact, the NIMH says the disorder is the leading cause of disability in the U.S. for people aged 15 to 44. George says that about half of all patients suffering from serious depression resist at least one antidepressant.

Changing brain chemistry
Unlike with electroconvulsive, or electroshock, therapy, where patients must be unconscious and administered muscle relaxants in order to prevent seizures, patients receiving rTMS (which involves trains of pulses during each session, hence the "repetitive" modifier) remain conscious and seated in outpatient settings. Highly focused magnetic pulses of up to 1.5 teslas induce an electrical current two to three centimeters deep in the left prefrontal section of the cerebral cortex. That region, which acts as an emotion modulator, appears to be underproducing neurotransmitters in depression sufferers. The rTMS pulses directly stimulate an area about the size of a quarter, although scientists are examining whether they affect other parts of the brain, too.

As with antidepressants, the electricity likely is changing the brain's chemistry, says rTMS pioneer Eric Wassermann, chief of the Brain Stimulation Unit at the National Institute of Neurological Disorders and Stroke in Bethesda, Md. He was among the first U.S. researchers to investigate rTMS as a way to alter mood.

Treatments typically occur five days a week for four to six weeks. FDA guidelines for first-time NeuroStar treatments call for 3,000 magnetic pulses delivered over 37.5 minutes (a rate considered low-frequency) by a C-shaped ferromagnetic coil held to the patient's scalp.*

*Correction (9/10/10): This sentence was edited after posting. It originally stated that the NeuroStar TMS Therapy System uses a figure 8–shaped magnetic coil.

7 Comments

1. 1. jtdwyer 02:49 AM 8/31/10

   The article states:
   "The prevailing theory is that people with depression do not produce enough of certain neurotransmitters, which include serotonin and dopamine. Electricity (administered in combination with antidepressants) stimulates production of those neurotransmitters."
   
   Based on this explanation, one can only agree with Aetna Insurance, who recently refused to reimburse for rTMS treatment, which it considers "experimental and investigational".
   
   Serious depression is a devastating, debilitating condition, but apparently positive results do not justify unleashing largely experimental treatment methods on the public.

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2. 2. EarthPulse 11:35 AM 8/31/10

   Treatments typically occur five days a week for four to six weeks. FDA guidelines for first-time NeuroStar treatments call for 3,000 magnetic pulses delivered over 37.5 minutes (a rate considered low-frequency) by a figure 8–shaped magnetic coil held to the patient's scalp....
   
   In terms of inconvenience and out of pocket cost; not to mention the physiological cost of consuming anti-depressive medication (until the GODS say you can use a simpler BETTER WAY)... is expensive no matter how you slice it.
   
   These dumb-a**es can't even tell if that electromagnet is stimulating "other parts of the brain". Really?... who are these people??? of course they are! just hold a pocket gauss meter under the jaw and you'll find hundreds if not thousands of gauss anywhere you move the sensor.
   
   What a crock of bull-s***. Just another way to charge you up the a** for something that is relatively inexpensive, totally convenient and should be readily available to anyone.
   

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3. 3. tate0774 04:03 PM 9/1/10

   People investingating into the possibilites of rTMS should read the patents and reports related to the research performed by Prof. Risto Ilmoniemi, Aalto University, Helsinki, Finland.
   His homepage is: http://www.biomag.hus.fi/ilmoniemi.html
   and here is a sample of his lectures available as iPod files:
   http://www.evicab.eu/bme/08ilmo/ipod/index.htm
   
   This comment was written by Taisto Leinonen, M.Sc.(electronics), who has been involved in TMS for some 30 years while teaching biomedical engineering in Helsinki, Finland, in two universities.
   

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4. 4. tate0774 04:06 PM 9/1/10

   Professor Risto Ilmoniemi, Aalto University, Helsinki, Finland has conducted investigations into rTMS for years and holds several patents. His lectures are available as iPod files here:
   http://www.evicab.eu/bme/08ilmo/ipod/index.htm
   

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5. 5. bolt1057@live.com.au 01:31 AM 9/2/10

   An effective anti depression treatment!! Sign me up!!

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6. 6. K. Karolak 05:37 PM 9/6/10

   Depression is not caused by chemical imbalance in the brain but by involuntary and on many occasions subconscious recall of traumatic memories from childhood, memories that were never properly emotionally processed by the brain. Recall of these fearful (painful) memories, often during sleep, causes reactivation of strong emotional responses (fight or flight reaction) and release into a bloodstream of fight or flight hormones; adrenaline, noradrenaline and cortisol (See http://en.wikipedia.org/wiki/Fight-or-flight_response). Prolonged circulation of fight or flight hormones in bloodstream causes drop in production of serotonin in a brain of affected individual and loss of brain connectivity ability to recall memories that cause depression. Administration of SSRI antidepressants causes increase in serotonin level and increase in brain connectivity and increase in recall of painful memories worsening emotional turmoil on many occasion leading to murder/suicides. Active neural connections that generate these painful memories have lower electrical resistance than inactive one. ECT treatment applied to both brain hemispheres causes that electric current flows through the brain following path of least resistance permanently frying most active neural connections located in corpus callosum part of the brain that connects brain hemispheres, resulting in loss of memories (loss of good memories that we complain about and loss of bad memories that permanently cures depression).
   
   rTMS treatment is very similar to ECT as it also fries active neural connections in the brain of an individual affected by depression but it is not as effective as ECT because it fries neural connections generating emotional responses in reaction to recall of traumatic memories.
   
   If you need more info and/or more evidence write to karol_karolak@live.ca
   

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7. 7. jgranger 11:48 PM 8/13/11

   For all the uninformed skeptics out there:
   I suffered from acute and debilitating depression for a few years in my late twenties. I tried everything, all sorts of drugs, read all the books, saw all sorts of therapists, tried meditating... I even got electroshock therapy. The latter helped a bit, but I lost 6 months worth of memory and I was in a daze for months afterwards. I don't recommend it except if it will save one from suicide. At last, I tried rTMS, which was then an experimental treatment. Within 10 sessions, I was back to normal, after 4 years of severe depression. It was unbelievable. It doesn't work for everyone, but it's worth a try. I did this in Canada, where I lived at the time, and I am certain it is cheaper there than in the US. In a few years, I imagine it will be covered, if not by health insurance, then by medication insurance - the math is obvious.
   I have been free of depression since (seven years now). If one day I find myself going back, I will get rTMS asap, regardless of cost...

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