Neuromod Blog

TMS possibilities for Parkinson's Disease ?

2009-03-28T08:22:00.000-07:00

MIT Technology Review published an article that goes into some research being done at Duke University which could be translated into a possible use for TMS.
Using a spinal cord stimulator on mice that have the rodent equivalent of Parkinson's the researchers were able to control the symptoms as well, or better than, Deep Brain Stimulation.
This makes me wonder if using a TMS coil over the spinal cord could achieve a similar effect for patients with Parkinson's?
Here is the abstract that was published in Science.

Gone for a While, Now I am Back!

2009-03-22T21:05:00.001-07:00

Things have been a bit slow on the Neuromod Blog due to life inserting itself between me and my passion, neuromodulation. New job (non-operative back and neck pain specialist for a large medical group), a move and a board exam later, and I am back.
New posts to follow. Stay tuned, this is an exciting time in neuromodulation. New discoveries and new studies are being published all the time, the pace of our understanding is increasing.
I was speaking with two colleagues the other day, one is a neurosurgeon and the other a plastic surgeon. We started to talk about the potential clinical/therapeutic benefits of neuromodulation and the best analogy I could think of was to equate our understanding of the brain and the possibilities for neuromod as something akin to opening a door to a dark room and realizing the room is big, but you are not sure how big. You yell to see how close the back wall is and all you really can tell is that the room is in fact something like a stadium.

TMS approved for Depression!

2008-10-09T08:36:00.001-07:00

WebMD just published a short blurb on one of their blogs stating that the FDA has cleared TMS for use in depression. They go on to state that there is now an indication for use in patients who have failed a trial of one antidepressant.
Now that this indication has been made, what will the next inidication be???? Stay tuned.

MIT article on tDCS

2008-06-27T09:39:00.000-07:00

The MIT Technology Review has a short article about research being done by the NIH. They interview Dr. Wasserman who has done a lot of work on non-invasive neuromodulation. He brings up some good points about the potential uses for tDCS, particularly in a healthy population. Can you imagine the demand for tDCS if high school senior find out that a nine volt battery could boost their SAT scores? Can you imagine the uproar in the Op-Ed pages? I think I can hear it from where I am sitting.....

Forbes article on Vascular Depression and TMS

2008-05-07T11:12:00.000-07:00

Forbes Magazine has a write-up about treatments for vascular depression that are up-and-coming. rTMS seems to be the front-runner. I will be excited to read the actual results of the study when they are published.

Neuromodulation Explained

2008-05-03T06:26:00.000-07:00

Here is an eloquent explanation of neuromodulation by Alan Wu, a neurologist at UCLA. I had the pleasure of meeting Dr. Wu while I was learning TMS and tDCS techniques at Dr. Alvaro Pascual-Leone's lab at Harvard.

Summary
Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are promising noninvasive cortical stimulation methods for adjunctive treatment of movement disorders. They avoid surgical risks and provide theoretical advantages of specific neural circuit neuromodulation. Neuromodulatory effects depend on extrinsic stimulation factors (cortical target, frequency, intensity, duration, number of sessions), intrinsic patient factors (disease process, individual variability and symptoms, state of medication treatment), and outcome measures. Most studies to date have shown beneficial effects of rTMS or tDCS on clinical symptoms in Parkinson’s disease (PD) and support the notion of spatial specificity to the effects on motor and nonmotor symptoms. Stimulation parameters have varied widely, however, and some studies are poorly controlled. Studies of rTMS or tDCS in dystonia have provided abundant data on physiology, but few on clinical effects. Multiple mechanisms likely contribute to the clinical effects of rTMS and tDCS in movement disorders, including normalization of cortical excitability, rebalancing of distributed neural network activity, and induction of dopamine release. It remains unclear how to individually adjust rTMS or tDCS factors for the most beneficial effects on symptoms of PD or dystonia. Nonetheless, the noninvasive nature, minimal side effects, positive effects in preliminary clinical studies, and increasing evidence for rational mechanisms make rTMS and tDCS attractive for ongoing investigation.

rTMS makes you stronger?

2008-05-03T05:50:00.000-07:00

A study by a group out of the University of Cologne in Germany has demonstrated that rTMS over the unaffected motor cortex of patients that have had a stroke will make their use of the affected hand more efficient and quicker.
The paper explains how rTMS is thought to work in a very nice manner and backs it up with a diagram that puts it into very understandable terms. Essentially there is imbalance between the two sides of the brain after a stroke. There are excitatory and inhibitory inputs from both sides of the brain which help us fine tune our movements, making them efficient, accurate and adaptable. Add a prehensile thumb and you start to understand the magnitude of the human brain. Now that we are figuring out how to rebalance a damaged brain the possibilities are becoming apparent. And I am sure that when we look back in twenty years or more at the preliminary data and concepts we will laugh at our shallow understanding of the subject.
Once again, I am amazed by the clinical implications of this. As a physiatrist (Physical Medicine and Rehabilitation specialist that works with stroke patients) I am encouraged and excited by the possibilities that are starting to present themselves. This is a technology that is going to revolutionize stroke rehabilitation; I am unsure if there are other advances that have occurred in this field that are comparable. The advent of clot busting drugs was a milestone, the development and use of advanced imaging techniques as well. Neuromodulation as a therapeutic intervention and as a research tool has staggering possibilities.

Medical Magnetism

2008-04-11T07:54:00.000-07:00

The Baltimore Sun has an article on TMS for depression and migraines online today. It starts with the usual TMS success story: someone with treatment resistant depression at the end of their rope is save by enrolling in a trial of TMS.
TMS seems to creeping into the common media. Maybe it is this way with anything cutting edge; at first the claims are too good to be true "Magnets cure everything!". Then they dig a little deeper into the medical literature, interview a few experts, local media picks up a few more success stories and WHAMMO! You have a critical mass of awareness. Is the wave starting to form?
LINK

Post-stroke Depression Treated with TMS

2008-03-04T20:03:00.000-08:00

The Archives of General Psychiatry just published a paper from the Department of Psychiatry at University of Iowa about using TMS to treat vascular-related depression. The results were pretty impressive.
Post-stroke depression is a well-known phenomenon, with a large percentage of people that have suffered a stroke showing signs and symptoms of depression. It seems that there is evidence that people with proven vascular disease (one of the side effects of uncontrolled diabetes/cholesterol/hypertension/smoking) have a higher incidence of depression.
These researchers took 90+ patients, with proven vascular disease and depression, and took them off of antidepressants. The divided them into two groups: sham and treatment groups. The treatment group got 12,000 pulses of TMS and the sham got, well, sham treatment with a fake coil. The treatment group a 33% drop on a depression scale while the sham group had a 14% drop, an appropriate placebo effect. The response rate in the placebo group was just under 7% while the response rate in the treatment group was 33%.
In the second experiment the treatment group got 18,000 pulses which resulted in a 42% drop in depression score while the sham group dropped 17%.
Once again, some interesting results that make you scratch your head and wonder if using a three tesla electromagnetic impulse could provide relief of depressive symptoms on par with antidepressants.....
Link

tDCS and aphasia after stroke

2008-02-12T12:08:00.000-08:00

One of the most common effects of a stroke is aphasia or the loss of the ability to comprehend and/or produce language. This accounts for much of the morbidity related to strokes.
In a study published by a group in Italy there is some convincing evidence that using tDCS can improve a naming task by 33% +/- 13%. This means that patients could demonstrate twenty to almost fifty percent improvement in naming. When you translate this into real-world recovery from stroke, the results are impressive.
As a tool for rehabilitation, and I am a physiatrist by trade (a rehabilitation doctor that directs the rehab of patients with diagnoses that include stroke), the clinical implications are significant.
PubMed Link

Lack of new posts....

2008-02-12T12:07:00.000-08:00

Sorry for the lack of posts recently, with the holidays and the fact I am currently looking for a job my postings have suffered.

IEEE article on TMS

2007-12-26T15:41:00.000-08:00

Nice article on TMS, and other neuromodulation technologies,in the IEEE Spectrum. The article was originally written in 2006 but it has some good insight into the world of neuromodulation. Reza Jalinous was interviewed for the TMS portion of the article as well as Dr. Pascual-Leone, whom I learned TMS and tDCS techniques from.

"Assuming that all the new brain stimulation techniques prove effective in the many upcoming trials, the psychiatrist's toolbox will look very different a decade from now. Patients will probably first be offered the less invasive techniques, such as transcranial direct current and magnetic stimulation; then the more invasive ones, such as the seizure therapies; and finally such surgical technologies as deep-brain stimulation and vagus nerve stimulation."

Illustration from IEEE Spectrum, by Matt Mahurin

TMS for Depression: a testimonial

2007-12-26T15:32:00.000-08:00

Here is a testimonial from an NBC affiliate on the use of TMS for depression. It seems like the patient had some great results.
When I think about all of the patients I have seen that have had a miserable time with the side effects of antidepressants I can't help but think that one could make an argument for using non-invasive neuromodulation as a first-line treatment.

Head Wounds are Good For You!

2007-12-26T15:21:00.000-08:00

At least that is what some studies have found about some Vietnam vets with certain head wounds.
Buzzle blogged about a study on vets with and without PTSD that found injuries to the prefrontal cortex or the amygdala were protective, at least with regard to developing PTSD.
Later in the article there is a suggestion that transcranial magnetic stimulation may play a role in the future treatment of PTSD based on these findings.

Postpartum Depression cured with TMS

2007-11-12T18:56:00.000-08:00

The St. Louis Post-Dispatch had an article (Link) this morning about a trial going on at Washington University using rTMS for postpartum depression. Only four patients have been treated at this point, but all four had resolution of their symptoms.

Within a few days after receiving her first treatment in February with the device, Meinert said she began to feel better. After two weeks, her symptoms were gone.

"It honestly was incredible. I was shocked to be feeling that well after two weeks," Meinert said. "I was feeling like my old self, and I still feel great today."

One of the points that this article makes is that standard antidepressants take up to four weeks to work. And in reality they may take longer... In addition there are a number of less than savory side effects that are fairly common with these drugs including " diarrhea, dry mouth, lethargy, nervousness, a bad taste in the mouth and loss of libido...". The author is obliquely getting at a point that I have mentioned before: maybe rTMS is a better starting point than the typical antidepressants that we currently reach for. Fewer side effects, potentially less cost, fewer interactions with other medications, the list could go on.
Another interesting point brought up is that the TMS unit used in this study was made by Neuronetics, the outfit that is working on getting an FDA indication for TMS and depression. This will be the first FDA indication for the transcranial application of TMS (currently it is my understanding that it is only approved for peripheral nerve stimulation). The word on the street is that Neuronetics should be getting this indication relatively soon, but that has been the word for several years.
All of the politics of the FDA and their approval process aside, it is my opinion (and just like every opinion out there, you can take it with a grain of salt..) that this is a major step forward in our options to clinically induce neuroplasticity and make a positive difference in the quality of someone's life.

Fibromyalgia pain reduced by rTMS

2007-10-28T17:05:00.000-07:00

A report from a group in France, published in the journal Brain, describes the effects of repetitive transcranial magnetic stimulation (rTMS) on self-reported average pain intensity recorded at baseline (before treatments), during 10 days of daily stimulation and then at 15, 30 and 60 days after the finish of treatments.
Thirty patients were divided up in a double blind fashion with one group getting sham treatment while the other got rTMS. Outcomes that were measured, meaning what effects were monitored during the study based on the researchers hypotheses, included depression monitoring scales, quality of life scales, scales that monitor how much pain interferes with the patient's functioning as well as the amount of pain a predetermined amount of pressure caused.
Twenty six of the original thirty, 13 in each group, were monitored through day 60 and the group that received the real rTMS had a significant reduction in pain , fatigue, morning tiredness, general activity and sleep at least two weeks after the last session was completed. The affective pain reduction was more long lasting than the sensory effects.
There were no significant side effects that occurred, as is the case with almost all of the studies that have been published in the last few years that adhere to published guidelines.
This group concluded that rTMS "...induces a long-lasting decrease in chronic widespread pain and may therefore constitute an effective alternative analgesic treatment for fibromyalgia."
Once again it seems that inducing neuroplasticity can help rebalance the maladaptive patterns that chronic pain syndromes have created. Is it the magic bullet we all hope for? Or is it snake oil? Or maybe something somewhere in between the two? Could this be another step in the right direction, opening the huge black box that is our brain just a little bit more?

Brain Mechanics at MIT

2007-10-16T20:25:00.000-07:00

Just read a very insightful article by Ed Boyden "an assistant professor in the MIT Media Lab and MIT Department of Biological Engineering, where he leads the Neuroengineering and Neuromedia Group." Link
He goes into some very insightful thoughts on how to approach the problems associated with fixing problems in the brain, particularly how to view the brain as a complex system that demand you approach a dysfunctional subsystem the same way a computer engineer would: by abstracting the problem and ignoring the surrounding complexity. He goes on to note that the tools could use to fix various problems will depend on what the nature of the problem is. Should we use something focal and invasive, or noninvasive yet cruder with regards to spatial resolution?
Boyden goes on with some nice thoughts about, you guessed it: TMS!
I have to admit I would love to have attended the Neuroengineering panel at the MIT Emerging Technologies Conference.
As I have said before, we are just starting to open the black box that is the brain and technology like TMS and fMRI, used by scientists like Boyden, are going to, at the very least, kick a wedge to keep that door cracked open.

Migraines Zapped with tDCS

2007-10-04T20:29:00.001-07:00

The same group ( I trained with them learning the technical aspects of tDCS and TMS) at Harvard that I have written about in the past just had an article published about one of their trials in IEEE Spectrum Online .

The gist of the article is that by using tDCS (low voltage electricity that runs through the brain via a couple of electrodes at very specific locations on the skull) migraineurs were getting some serious relief. The study is currently ongoing so the results have yet to be seen.

"The investigators, Dr. Felipe Fregni and Soroush Zaghi, both of Harvard Medical School, have recruited 24 patients who suffer migraine headaches at least 15 times per month. At scheduled intervals, which may or may not coincide with migraines, Fregni attaches electrodes to a subject’s scalp and passes 2 milliamps of current through the brain, targeting the locus of pain. Two months into the study, he is encouraged by what he is seeing. “In the initial sample, the results went in the direction we predicted,” he says. One of the main themes that I walked away from my week at Harvard with was that the brain is a HUGE BLACK BOX!!!! The breadth and depth of our understanding of how and why the brain works the way it does is superficial at best. As a result of the basic science that is going on with all of the new tools available to researchers, including TMS and fMRI, we are starting to crack open the box. But every little tidbit we figure out just makes me realize that the volume of the box is staggering."

A colleague asked me recently what the proposed mechanism of action was for tDCS and TMS. My short answer was "I don't really know". The long answer has to do with re-balancing the excitatory and inhibitory inputs of certain areas of the brain that affect areas "down stream" from the area of action.

"Following that theory, what triggers migraines is just an extreme example of what causes ordinary headaches in the normal brain. “If you stay up all night, three days in a row, and there are loud sounds and bright lights, you’re going to get a headache, too,” Fregni says. For people with migraines it just takes much less stress because the baseline of activity in certain areas of the brain is much higher, he says.  Neurons, the cells that carry messages throughout the brain, are constantly receiving electrical inputs from surrounding cells. They integrate the voltage signals, and if the total is strong enough the neuron fires—sending a pulse of voltage out to other neurons to which it’s connected.  During tDCS, the current hyperpolarizes the afflicted area of the brain, making the neurons less likely to fire. In the short term, the treatment usually staves off an encroaching attack, but tDCS could have long-term benefits as well. Many studies have determined that when repeatedly exposed to a hyperpolarizing current, neurons eventually become less excitable, a process called long-term depression. The stimulation would take advantage of that phenomenon to prime the migraine-prone regions of the brain so that one great flash of light would not be enough to overload the whole system."

Migraines Zapped with tDCS

2007-10-04T20:29:00.000-07:00

TMS Demonstrates Increased Cerebral Blood Flow

2007-10-01T21:13:00.000-07:00

Nice write up on an article in Science showing that TMS causes an increase in cerebral blood flow as a result of increased neuronal activity. I will get my hands on the actual article and see what it has to say. But regardless, this is some interesting data which helps open the black box that is the brain just a little bit wider. Nice work by the group at Cal.

Neuroscientists connect neural activity and blood flow in new brain stimulation technique

By Sarah Yang, Media Relations | 27 September 2007

BERKELEY – Neuroscientists at the University of California, Berkeley, have for the first time measured the electrical activity of nerve cells and correlated it to changes in blood flow in response to transcranial magnetic stimulation (TMS), a noninvasive method to stimulate neurons in the brain.

Their findings, reported in the Sept. 28 issue of the journal Science, could substantially improve the effectiveness of brain stimulation as a therapeutic and research tool.

With technological advances over the past decade, TMS has emerged as a promising new tool in neuroscience to treat various clinical disorders, including depression, and to help researchers better understand how the brain functions and is organized.

TMS works by generating magnetic pulses via a wire coil placed on top of the scalp. The pulses pass harmlessly through the skull and induce short, weak electrical currents that alter neural activity. Yet the relative scarcity of data describing the basic effects of TMS, and the uncertainty in how the method achieves its effects, prompted the researchers to conduct their own study.

"There are potentially limitless applications in both the treatment of clinical disorders as well as in fundamental research in neuroscience," said Elena Allen, a graduate student at UC Berkeley's Helen Wills Neuroscience Institute (HWNI) and co-lead author of the study. "For example, TMS could be used to help determine what parts of the brain are used in object recognition or speech comprehension. However, to develop effective applications of TMS, it is first necessary to determine basic information about how the technique works."

Other techniques for studying neural activity in humans, such as functional magnetic resonance imaging (fMRI) or electroencephalogram (EEG), only measure ongoing activity. TMS, on the other hand, offers the opportunity to non-invasively and reversibly manipulate neural activity in a specific brain area.

In a set of experiments, the researchers used TMS to generate weak, electrical currents in the brain with quick 2- to 4-second bursts of magnetic pulses to the visual cortex of cats. Direct measurements of the electrical discharge of nerve cells in the region in response to the pulses revealed that TMS predictably caused an initial flurry of neural activity, significantly increasing cell firing rates. This increased activity lasted 30 to 60 seconds, followed by a relatively lengthy 5 to 10 minutes of decreased activity.

What the researchers were able to determine for the first time was that the neural response to TMS correlated directly to changes in blood flow to the region. Using oxygen sensors and optical imaging, the researchers found that an initial increase in blood flow was followed by a longer period of decreased activity after the magnetic pulses were applied.

"This long-lasting suppression of activity was surprising," said Brian Pasley, a graduate student at HWNI and co-lead author of the study. "We're still trying to understand the physiological mechanisms underlying this effect, but it has implications for how TMS could be used in clinical applications."

The critical confirmation of the connection between blood flow and neural activity means that researchers can use TMS to alter neural activity, and then use fMRI, which tracks blood flow changes, to assess how the nerve cells respond over time.

"One of the most exciting applications of TMS is the ability to non-invasively modify neural activity in specific ways," said Pasley. "The brain is malleable, so brain stimulation may be used to alter and promote specific functions, like learning and memory, or suppress abnormal activity that underlies neurological disorders. If we can figure out the right ways to stimulate the brain, TMS will likely be useful in attempts to improve neural function."

The researchers noted that one of the difficulties in using TMS for specific applications is the fact that its effects vary in different brain regions and individuals.

"Using TMS is inherently challenging because its neural effects can be so variable," said Ralph Freeman, UC Berkeley professor of vision science and optometry and principal investigator of the study. "Fortunately, we can determine empirically what the end result is by making measurements with fMRI. This should be valuable to clinicians who must evaluate the effectiveness of a stimulation treatment. In turn, fMRI may serve as a guide to determine adjustments in treatment parameters."

The study was also co-authored by Thang Duong, a UC Berkeley graduate student in vision science. The National Eye Institute of the National Institutes of Health and the National Science Foundation helped support this research.

New Posts Coming Soon!

2007-09-23T20:31:00.000-07:00

I have been on vacation for a week, then traveling for a week, home for a week and now off again for another conference. I WILL get some new material up here soon.
Just a little tidbit before I go: one of the weeks I spent away in September was at Harvard getting trained on TMS and tDCS. All I can say is that I was blown away with how much clinical potential these techniques have. There are an incredible number of people out there could be helped with these techniques and other techniques that will develop as a result of the research that is going on now. This is not a magic pill that cures all, but they could make a large impact on the quality-of-life of a large portion of the population.
More to come after I get back from my trip out of town for the next week.

A 9v battery for Depression????

2007-09-05T14:24:00.000-07:00

The same group out of Brazil and Harvard published that I have mentioned in the blog previously, published an article in June on using tDCS for major depression.

A randomized, double-blind clinical trial on the efficacy of cortical direct current stimulation for the treatment of major depression.

A total of 40 patients were recruited and randomized to once of three groups: anodal stimulation of the occipital cortex, anodal tDCS of the left dorsolateral prefrontal cotex (DLPFC) and sham. All patients had been diagnosed with major depression and were medication-free for two months at the time of the study.

Outcomes were the Beck Depression Inventory and the Hamilton Depression Rating Scale, two of the most commonly used outcome measures used in similar depression studies.

All of the participants underwent tDCS with 2mA of stimulation for twenty minutes for 10 days (weekdays over two weeks.) One interesting tid bit that the authors mentioned was that the effects of tDCS are cumulative.

Participants were assessed at baseline and then immediately after the sessions were over, at 15 days and at 30 days using the Ham. D and the BDI. Clinical response was defined as at least a 50% decrease in the Ham D score from baseline and remission was assigned a score of seven or less.

There were no serious adverse effects noted during or after the sessions. Only a few headaches, itching at the site of stimulation and redness at the site of pad attachment.

There were 8 responders in the DLPFC group (out of 21) and 5 remissions. The occipital group had 2 respond (out of 9) with no remissions and the sham group had no responders and no remissions.

The effects of the tDCS lasted at least 30 days after the last session.

Once again, the effects of the tDCS are being attributed to neuromodulation of the activity of the DLPFC "...induc(ing) a change in the DLPFC activity, a critical area in the cortico-subcortical, mood-related neural network."

Just think, for twenty minutes a day there were 13 of the 21 participants that had at least a fifty percent improvement. All with a nine volt battery.

Maybe I should regress back to being a young kid and start licking batteries more often???????

rTMS for Bipolar Disorder

2007-08-14T12:51:00.000-07:00

An article about Brainsway and their trials on using rTMS for Bipolar disorder.

Brainsway Ltd. (TASE:BRIN) reports positive
interim results in the clinical trial of its Deep TMS transcranial magnetic
stimulation device for the treatment of bipolar disorder on patients who did not
respond to any medications.
The findings are based on the interim report by
the chief researcher on the nine patients in the study at the Shalvata
Psychiatric Hospital in Israel. The effect of Deep TMS on the patients was
measured using different methods for measuring depression, such as the Hamilton
Depression Rating Scale (HDRS), and self questionnaires.
The study found that all the patients
responded positively to the treatment, compared with previous treatments using
antidepressants. There were no complaints or side effects, except for slight
headaches that some patients felt after the treatment and which quickly passed.
The chief researcher at Shalvata said that the study was the first evidence
that Deep TMS was an effective treatment for bipolar disorder, with the caveat
that this was only the beginning.
Brainsway also reported the results of a
study on the effectiveness and safety of the use of Deep TMS for the treatment
of major depression in cases where patients did not respond to medications.
These findings are based on a preliminary report by the chief researcher on 54
patients participating in the trial at Shalvata.
Published by Globes Israel business news - www.globes.co.il - on August 8, 2007

Zap the Brain to cut Alcohol Craving

2007-08-14T07:39:00.000-07:00

Scientists at Harvard and in Brazil have just published a study that shows using low voltage current delivered through a pair of saline-soaked sponges to specific sites on the head can cut down an alcoholics craving for alcohol.

Prefrontal cortex modulation using transcranial DC stimulation reduces alcohol craving: A double-blind, sham-controlled study.

Previously studies have shown that high-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) can cut down smoking and cocaine craving. They postulated that by using tDCS to apply "subthreshold neuronal membrane depolarization" as a result of electrical current flow they could mimic the effects of rTMS. They had previously shown that tDCS delivered to both sides of the brain could reduce the craving for smoking and a craving for alcohol has been shown to increase activity in the DLPFC, so they juiced up some volunteers.

The study design was double-blind, sham-controlled, cross-over study that stimulated the brain using two mirror-image montages: one placed the active anode over the left DLPFC and the one that placed it over the right. The third was a sham control. They used validated scales to measure alcohol craving as well as side-effect questionnaires for tDCS. 13 subjects were examined at baseline and then went through the different protocols. The stimulation used 2mA for 20 minutes. They were shown videos, both before stimulation or sham stimulation, as well as after, that exposed them to alcohol cues for five minutes. After the exposure they were questioned about their craving for alcohol.

After the subjects were exposed to alcohol cues there was an 8% increase in their craving. There was a decrease in cravings after both left and right anode stimulation of 20-27%! To make things even more interesting cravings could not be increased by alcohol cues after the stimulation with active electrodes but it could be increased in the sham group.

Their conclusion is that "...both anodal left/cathodal right and anodal right/cathodal left DLPFC stimulation significantly decreased craving as compared to sham stimulation." They then go on to suggest the possible mechanisms for the changes including alteration of activity in the dopamine pathways.

"One potential advantage of developing tDCS as an alternative therapeutic strategy is the fact that the effects of tDCS are immediate.""...a single treatment that can transiently block craving levels quickly would be highly desirable compared to drug treatment therapies that are typically more long-lasting and lead to tonic effects and thus can-not capture craving variations."

Side-effects were very mild.

Better rTMS studies? Where are we headed??

2007-08-07T21:04:00.000-07:00

Browsing Pub Med for TMS related subjects and came across an article whose authors include Dr. Pascual-Leone and Dr. Fregni, both from Harvard. They did a meta review of TMS (and incidentally a both prolific researchers looking at rTMS, tDCS etc..) and it's effects on depression from articles published in the last year and it seems that there is an improved effect of TMS on depression in these papers versus earlier studies.
Is this a result of improving science behind the use of TMS, more accurate TMS protocols, more studies????
Anyone have any thoughts on the subject????

Has repetitive transcranial magnetic stimulation (rTMS) treatment for depression improved? A systematic review and meta-analysis comparing the recent vs. the earlier rTMS studies.

Autism and TMS

2007-08-07T20:48:00.001-07:00

It seems that there is some evidence that the effects of autism can be altered by TMS. This is news to me, I am going to have to do a little Pub Med sleuthing to see what the word on the scientific street is.
It would make sense that by altering an already skewed balance of hyper and hypo excitability you would be able to alter the balance of the brain activity.
Turns out there is a total dearth of science regarding TMS as a treatment for autism. A PubMed search only gave me one article that was in a journal of scientific hypotheses.
Here is the article from about.com

Motor Cortex Stimulation and Motor Recovery

2007-07-24T21:51:00.000-07:00

A recent paper published in Neurosurgery looked at motor recovery in patients with ischemic stroke at least four months out from the start of the study. All had moderate motor weakness. A treatment group had electrode implantation and the control group received the same three weeks of rehabilitation that the study patients received after their implants. Implanted patients were stimulated only during therapy.
All of the patients were followed for 12 weeks after their rehabilitation. And the results were pretty good: the implant group had significantly better scores on the Fugl-Meyer and hand function portion of the Stroke Impact Scale.
My conclusion was that motor cortex stimulation can improve motor recovery after a stroke, particularly in a patient without a dense hemiplegia and that motor cortex stimulation provides additional benefit to patients compared to rehabilitation, alone.
This is a nice example of improved motor recovery as a result of neuromodulation. I am going to have to go dig into my files to find a paper I read and tucked away that commented on the positive predictive value of TMS in anticipating a positive response to implanted motor cortex stimulators. Is anyone aware of any studies that compare motor recovery ( would that be a head to head study......anyone, Bueller????) with TMS vs implanted stimulation??

Wired Magazine TMS blurb

2007-07-24T21:40:00.001-07:00

I just got the most current issue of Wired about and there was a nice little piece by Melinda Wenner on TMS and it's possibilities.

"Brains are electric — when neurons talk, they speak in voltage. Now, a new technique called transcranial magnetic stimulation may let neuroscientists hack those conversations. TMS translates electric signals into a magnetic field that passes through the skull and into the brain. Too much juice can cause seizures, but calibrate the machine just right and you can actually control brain activity. Treatments for drug-resistant depression, migraines, and post-traumatic stress disorder are in the offing. Further out, some researchers are trying to trigger more restful power naps, and others are working with autistic savants, hoping to inhibit the autism and bring forward the Rain Man level detail processing. That's right: We could all be perpetually happy, relaxed, and brilliant if they'd just mount this thing in a baseball cap."

Hmmm, a baseball cap with a figure 8 coil in it....maybe she is on to something here? As the scientific evidence grows, I am realizing she might not be so far off.

Recent paper on rTMS and pain

2007-07-01T20:40:00.000-07:00

The Journal of Pain just published a review article on the effects of rTMS on experimentally induced and chronic neuropathic pain. They looked at a seven studies that used rTMS to modulate experimentally induced acute pain brought on by ischemic muscle pain, cold immersion, capsaicin or laser stimulation. Those last tow really get to me, I am still recovering from a traumatic expericence as a child at a Mexican restaurant in California. I must have been about four and I grabbed a chip-full of homemade salsa that must have been served to the devil himself it was so hot. All I remember after being stunned by the growing four alarm fire in my mouth was the busboy grabbing a glass of milk and pouring it down my gullet. And anything involving lasers requires the obligatory reference to Dr. Evil's "sharks with lasers.."
It seems the findings in the acute pain papers were mixed. The authors conclude that "The varied effects of rTMS on acute pain may have been influenced by the type of experimentally induced pain, the stimulation frequencies used, and the cortical sites of rTMS stimulation." They noted some of the findings from this group of papers included that ability of single session rTMS to alter pain thresholds.
There were 16 chronic neuropathic pain papers that were included in this group that included approximately 250 patients with a wide variety of conditions including thalamic stroke, trigeminal neuralgia, CRPS, peripheral neuropathy, spinal cord injury, brahcial plexus injury, back pain, thalamotomy pain and osteomyelitis. The papers included used varying protocols including single session and multiple sessions.
In eight of the studies there was a "significant decrease in post-TMS VAS (visual analog scale, usually a 0-10 scale of pain) means as compared with pretreatment means...". To confuse issues there were some studies that reported a decreased in studies that used sham TMS to control for the placebo effect. However, the post-TMS VAS scores were significantly lower than the sham scores.
Some of the numbers that the authors present caught my eye: 62% of patients acheived at least 30% reduction in pain based on their VAS scores after TMS and almost 30% of those patients had at least a 50% drop in their pain score.
They then go on to make some generalizations about TMS protocols including the type of coil used, fast vs slow, the number of pulses used and the location of stimulation. None of the studies reported any adverse affects.
Once again, this presents some thought provoking information and causes me to continue to consider therapeutic neuromodulation with TMS may be in our future.
At what point does someone take the plunge and start offering this to patients with refractory neuropathic pain. I have seen these patients and they are miserable. Their pain is their life, and if you could offer someone a 30-50% reduction in their pain, even if it involved ongoing treatment, I have to wonder if this would be potentially life-altering. Just a thought....

NY Times Book Review on Neuroplasticity

2007-05-29T19:41:00.000-07:00

The New York Times has a review on a book published recently by Norman Doidge that reports on the revolution/evolution of the science surrounding neuroplasticity.

The credo of this revolution is neuroplasticity — the discovery that the human brain is as malleable as a lump of wet clay not only in infancy, as scientists have long known, but well into hoary old age......
Dr. Doidge, a Canadian psychiatrist and award-winning science writer, recounts the accomplishments of the “neuroplasticians,” as he calls the neuroscientists involved in these new studies, with breathless reverence. Their work is indeed mind-bending, miracle-making, reality-busting stuff, with implications, as Dr. Doidge notes, not only for individual patients with neurologic disease but for all human beings, not to mention human culture, human learning and human history.

This should be some interesting reading. I will get some thoughts on this books into the blog as soon as I get my hands on a copy and get through it.
If you have read the book I would like to hear what you have to say.

Wired Article on TMS

2007-05-21T22:40:00.000-07:00

Interesting blog entry from Wired on the handheld TMS unit by Neuralieve. I know relatively little about the actual power of this unit and I have to admit that I am little skeptical of the ability to accurately focus and the ability to penetrate with such a small unit. A little more reading is in order.....Anyone out there with an opinion on this technology???

Wired Article on TMS

Neuralieve Website

tDCS for major depression

2007-05-19T21:39:00.000-07:00

Nice study done by Fregni et al. looking at treating depression with transcranial direct current stimulation (tDCS) for 20 min/day for five days. The patients, n=10, were divided into a control group getting sham treatment and a treatment group. All subjects were evaluated with the Hamilton and Beck Depression Inventories prior to and after treatment (or sham treatment). The treatment group HAM and BDI scores improved approximately 60% and 65%, respectively. The sham group improved 10% and 25%, respectively.
As the authors state, "The importance of this study lies in the fact that this treatment is inexpensive, easy to administer, non-invasive and painless."
They go on to say that the effects of tDCS are most likely related to neuronal depolarization and prolonged enhancement of the excitability of the left dorsolateral prefrontal cortex. This stimulation may re-equilibriate the balance of excitation/inhibition in that area of the brain.
As the basic science is accumulating, and the CNS imaging techniques improve, it seems like resetting this excitation/inhibition balance is one of the keys to neuromodulation whether it is with tDCS, TMS, pharmacology or psychological approaches.

Treatment of major depression with transcranial direct current stimulation.

Mayo Clinic article on TMS for the public

2007-05-16T20:37:00.000-07:00

Here is a link to a post from mayoclinic.com about TMS and how it works. I am curious about who the authors are for this article, I posted about the article that first introduced me to TMS and that article came out of the Mayo Clinic.
Mayoclinic.com

Newsweek Article on TMS

2007-05-16T20:29:00.000-07:00

Here is a link to an article that appeared in Newsweek on TMS. It seems to give a fair evaluation of some of the pros and the cons of TMS. Nice that they identified Dr. Pascual-Leone in the article considering the breadth and depth of research that he has done.
Newsweek article

Slow-Frequency rTMS and Fibromyalgia Pain

2007-05-16T20:06:00.000-07:00

This was the first article I read that introduced me to the concept of transcranial magnetic stimulation. I had just seen a patient the day before in a Rheumatology clinic I was visiting and had a long chat with the Rheumatologist I was working with about the etiology of Fibromyalgia and what sorts of treatments were available. Needless to say, he was fairly pessimistic about what was possible. I ran across this article in Rehab in Review, it piqued my interest and I pulled the article.
Some thoughts about the article: an n of four is always concerning, so it needs to be considered a limited case series. But if you examine the response of the patients to repetitive transcranial stimulation (rTMS), it was pretty amazing. A baseline pain of 8.2(ranging from 7-9.5 on a scale of 0-10) that was dropped to 1.5 (0-3.5) is not only statistically significant, but if you consider the functional ramifications it is amazing. These subjects received rTMS five days per week for four weeks, one of the patients received sham rTMS prior to the four weeks and one got an additional twelve treatments because she (they were all women) had remission of depressive symptoms. All had been diagnosed by board certified Rheumatologists and all had been evaluated by Psychiatrists.
The results showed one patient had resolution of depression and two of the four had resolution of their pain. Pain was improved, defined as not increasing more than 1.5 points on the 0-10 scale, for 15-27 weeks.
This was a real eye-opener for me even when taken with a large grain of salt. Just something to think about.
PubMed Citation

Welcome to the Neuromodulation Blog! Neuromod

2007-05-12T11:22:00.000-07:00

This blog is dedicated to exploring the many different methods of neuromodulation and their potential therapeutic uses. Examining the possibilities and the rapidly accumulating basic science has become a passion of mine and I would like to create a blog where scientific articles can be explored and commented upon by the basic science, medical and lay-person communities.
I will start to post links to articles that have caught my attention and link to them in PubMed. Please feel free to post comments and provide links.
Some of the areas I will explore are transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS) and percutaneous nerve stimulation (PNS-an acupuncture technique).
This is not the sole scope of this blog, just a starting point.