Medical Batteries – The History of Electrotherapy

Update 2/17/17 BBC The strange Victorian fashion of self-electrification
tdcslindstroms-electro-medical-apparatus

If you’ve been following along very closely you may recall that podcast episode #6 guest Anna Wexler mentioned in passing that she had been researching Ye Olde practice of therapeutically applying current to various parts of the body. Well, an early version of a new paper of hers landed the other day: Recurrent themes in the history of the home use of electrical stimulation: Transcranial direct current stimulation (tDCS) and the medical battery (1870–1920). It’s behind a paywall but here are some highlights.

  • Although the home use of tDCS is often referred to as a novel phenomenon, in reality the late nineteenth and early twentieth century saw a proliferation of electrical stimulation devices for home use.
  • In particular, the use of a portable electrotherapy device known as the “medical battery” bears a number of striking similarities to the modern-day use of tDCS.
  • Many features related to the home use tDCS—a do-it-yourself movement, anti-medical establishment themes, conflicts between lay and professional usage—are a repetition of themes that occurred a century ago with regard to the medical battery.
  • A number of features seem to be unique to the present, such as the dominant discourse about risk and safety, the division between cranial and non-cranial stimulation, and utilization for cognitive enhancement purposes.
  • Viewed in historical context, the contemporary use of electrical stimulation at home is not unusual, but rather the latest wave in a series of ongoing attempts by lay individuals to utilize electricity for therapeutic purposes.

Lots of ‘medical battery’ patents here.
And a ton of wonderful images to be found in books in Google’s digitized library.
Most of these came from a single book!

 

“Cognitive Enhancement by Non-invasive Brain Stimulation” with Roy H. Hamilton

An intelligent introduction to tDCS and TMS in the context of Cognitive Enhancement. Dr.  Roy Hamilton (at around 19:00 in the video, the beginning is basic intro boilerplate) discusses studies which demonstrate significant positive cognitive effects in healthy individuals. I especially liked Dr. Hamilton’s take on the concerns and potential risks of non-invasive brain stimulation which he discusses towards the end of his talk.

tDSC Papers of Note April 2013

Regional personalized electrodes to select transcranial current stimulation target (pdf)
…with the present work we developed a procedure to properly shape the stimulating
electrode.
Regional-personalized-electrodes-to-select-transcranial-current-stimulation-target

(The familiar looking square electrodes were the reference electrodes.)
Tags: electrodes, tACS

The Sertraline vs Electrical Current Therapy for Treating Depression Clinical StudyResults From a Factorial, Randomized, Controlled Trial (pdf)
At the main end point, there was a significant difference in Montgomery-Asberg Depression Rating Scale scores when comparing the combined treatment group (sertraline/active tDCS) vs sertraline only, tDCS only, and placebo/sham tDCS… There were 7 episodes of treatment-emergent mania or hypomania, 5 occurring in the combined treatment group.
Tags: depression

Noninvasive transcranial direct current stimulation over the left prefrontal cortex facilitates cognitive flexibility in tool use (pdf)
The results support the hypothesis that certain tasks may benefit from a state of diminished cognitive control.
And a related news story discussing the same paper.
Brain hacking: Electrifying your creative side
Each person was shown pictures of everyday objects and asked to come up with a new uses for them.
The group which received the TDCS muting the left prefrontal cortex was better in coming up with unusual uses than the others — and did it faster.
Tags: creativity, Sharon Thompson-Schill, cathodal stimulation,

 Orchestrating neuronal networks: sustained after-effects of transcranial alternating current stimulation depend upon brain states (pdf)
Long lasting after-effects foster the role of tACS as a tool for non-invasive brain stimulation and demonstrate the potential for therapeutic application to reestablish the balance of altered brain oscillations.
Tags: tACS

Different Current Intensities of Anodal Transcranial Direct Current Stimulation Do Not Differentially Modulate Motor Cortex Plasticity (pdf)
targeting M1 …10 minutes of anodal tDCS at 0.8, 1.0, and 1.2 mA
These results suggest that the aftereffect of anodal tDCS on facilitating cortical excitability is due to the modulation of synaptic mechanisms associated with long-term potentiation and is not influenced by different tDCS intensities.
Tags: M1, dosage

Transcranial direct-current stimulation increases extracellular dopamine levels in the rat striatum (pdf)
Following the application of cathodal, but not anodal, tDCS for 10 min, extracellular dopamine levels increased for more than 400 min in the striatum. There were no significant changes in extracellular serotonin levels.
Tags: dopamine

Spark of Genius: A new technology promises to supercharge your brain with electricity. Is it too good to be true?
Surprisingly good pop-sci overview of where we’re at with tDCS. Chock full of relevant links.

Using computational models in tDCS research and clinical trials (pdf)
Hypothesis: Appropriately applied computational models are pivotal for rational tDCS dose selection.
Tags: Comptational modeling, Marom Bikson,

Boosting brain functions: Improving executive functions with behavioral training, neurostimulation, and neurofeedback  (pdf)
This review provides a synopsis of two lines of research, investigating the enhancement of capabilities in executive functioning: a) computerized behavioral trainings, and b) approaches for direct neuromodulation (neurofeedback and transcranial electrostimulation).
Tags: cognitive enhancement

Focal Modulation of the Primary Motor Cortex in Fibromyalgia Using 4×1-Ring High-Definition Transcranial Direct Current Stimulation (HD-tDCS): Immediate and Delayed Analgesic Effects of Cathodal and Anodal Stimulation (pdf)
We found that both active stimulation conditions led to significant reduction in overall perceived pain as compared to sham.
Tags: Fibromyalgia, HD-tDCS, Marom Bikson, pain

Catching Up – Articles of Note January 2013

Neurobiological Effects of Transcranial Direct Current Stimulation: A Review
The purpose of this systematic review is to summarize the current knowledge regarding the neurobiological mechanisms involved in the effects of tDCS.

Neuroenhancement of the aging brain: restoring skill acquisition in old subjects.
The main finding was that old participants experienced substantial improvements when training was applied concurrent with tDCS, with effects lasting for at least 24 hours.

Examining transcranial direct-current stimulation (tDCS) as a treatment for hallucinations in schizophrenia.
Auditory verbal hallucinations were robustly reduced by tDCS relative to sham stimulation…

Modulation of training by single-session transcranial direct current stimulation to the intact motor cortex enhances motor skill acquisition of the paretic hand.
tDCS facilitated the acquisition of a new motor skill compared with sham stimulation…

Interactions between transcranial direct current stimulation (tDCS) and pharmacological interventions in the Major Depressive Episode: Findings from a naturalistic study.
tDCS over the DLPFC acutely improved depressive symptoms…

Amelioration of cognitive control in depression by transcranial direct current stimulation.
Deficient cognitive control over emotional distraction is a central characteristic of major depressive disorder (MDD)
The present study demonstrates that anodal tDCS applied to the left dlPFC improves deficient cognitive control in MDD.

Transcranial direct current stimulation of the motor cortex in the treatment of chronic nonspecific low back pain: a randomized, double-blind exploratory study.
No significant effect was seen in the primary outcomes between active and sham stimulation

Comparing immediate transient tinnitus suppression using tACS and tDCS: a placebo-controlled study.
…bifrontal tDCS modulates tinnitus annoyance and tinnitus loudness, whereas individual alpha-modulated tACS does not yield a similar result.

Review of transcranial direct current stimulation in poststroke recovery.
In this review, we summarize characteristics of tDCS (method of stimulation, safety profile, and mechanism) and its application in the treatment of various stroke-related deficits, and we highlight future directions for tDCS in this capacity.

 

Michael Weisend – Mind Research Network DIYtDCS Podcast #4

Dr. Michael WeisendMichael Weisend PHD. is a principal investigator at The Mind Research Network, MRN.org, and assistant professor of Translational Neuroscience at the University of New Mexico, Albuquerque. Dr. Weisend and his team pioneered a method for determining optimal brain regions for tDCS stimulation using fMRI. Much of Dr. Weisend’s work is focused on cognitive enhancement in healthy subjects for the purpose of reducing the amount of time it takes to master a skill. He shared a full hour of his time and a wealth of tDCS-related information. Download the interview here (zipped mp3). Subscribe in iTunes. (Firefox users- there’s an issue with the html5 audio player. In the meantime you can download the episode or open the page in another browser).

Show Notes
The Sally Adee article I discuss. (pdf)
The Through The Wormhole episode mentioned. (YouTube)
Magnetoencephalography
DARPA The Defense Advanced Research Projects Agency
DARWARS Ambush NK is a research program intended to accelerate the development and deployment of military training systems. (wiki) (pdf)
TDCS guided using fMRI significantly accelerates learning to identify concealed objects.
eeg electrodes + gel + wrap.
Transcranial direct current stimulation’s effect on novice versus experienced learning.
iNTIFIC Develops games and training.
pulsed oscillatory electromagnetic fields
tRNS
Fisher Wallace Stimulator.
Perils of tDCS.
F10-anodal, cathodal-opposite upper arm, actually does something.
‘Target search and identification’. What could it be good for the average person?
Dear reader, help me find a way to build a self-experiment that will test my results.
Recalling distant memories?
Anecdotes…
Girl who heard melodies.
Guy who solved a problem he’d been working on.
Age-related memory decline… ‘I can find words now…’
-More verbally fluent as a result of tDCS
-Left Inferior Frontal Gyrus (approx F5-anode, cathode opposite upper arm)
“People do not like it.” Cathodal stimulation of F10
Accelerating non-declarative skill learning.
-Cathode-L-DLPFC, Anode-M1
Grants outstanding to test more of this.
Recruiting the correct brain network to deal with the stimuli at hand for the purpose of successful task completion.
Competing brain networks!
Neural modulation fastest growing area of medicine.
Ethics of tDCS.
Lisa Marshall
Potential for-profit applications?
Conferences: Human Brain Mapping, Seattle June 16-20
Society for Neuroscience San Diego Nov 9-13

A Treasure Trove of Stimulating Information!

universityNMJust found this in iTunesU. Wow! You’ll recognize many of these names if you’re reading the tDCS literature. I’ve only watched the Michael Weisend talks (whom we met earlier on the blog) so far. I have a much better understanding of the difficulty of running a tDCS trial now. There’s a lot that can go wrong. If your protocols aren’t set up just right, your information might be useless. Here’s the web link iTunes Link from which you can download in iTunes. Downloads are quite slow.

Introduction to Neurosystems Engineering, Spring 2011 (ECE 595)                   Neurosystems Engineering is an emerging field at the intersection of Neuroscience, Psychology, and Engineering, and the University of New Mexico is its epicenter.

Course Intro   Dr. Gerold Yonas
Course Syllabus   Dr. Gerold Yonas
Tools and Techniques in Neuronal Stimulation  Dr. Edl Schamiloglu
Basic Principles of Feedback and Control   Prof. Chaouki T. Abdallah
Discussing the Course General Approach and Direction  Dr. Gerold Yonas
Effects of Direct Current, Non-Invasive Brain Stimulation on Learning  Michael Weisend
In the Laboratory Transcranial Direct Current Stimulation (tDCS)   Michael Weisend
Posttraumatic Stress Disorder: Roles for Treatment & Prevention (Part I) Dr. Pilar M Sanjuan
Posttraumatic Stress Disorder Roles for Treatment & Prevention (Part II) Dr. Pilar M Sanjuan
Tour of the Mind Research Network   Dr. Vince D. Calhoun
Neuroimaging of Intelligence and Creativity (Part I)    Dr. Rex E. Jung
Neuroimaging of Intelligence and Creativity (Part II)   Dr. Rex E. Jung
Memories and Migraines: Application of tDCS  Laura Matzen
Neurochemistry Application in NonInvasive Brain Stimulation  Dr. Charles Gasparovic
Non-Invasive Brain Stimulation    1:03:47   Lucas C. Parra
Epilepsy, Autism, and Novel Treatment Strategies   Dr. Jeffrey David Lewine
The Emerging Field of Sleep Disorders Medicine  Dr. Barry Krakow
Presentation of Class Projects   Student

Marom Bikson of Soterix Medical and CUNY – DIY tDCS Podcast Episode #3

Marom Bikson is CEO of Soterix Medical and Associate Professor at City College of New York in the Department of Biomedical Engineering. Marom is a distinguished tDCS scientist and prominent in the development of HD-tDCS. Download the interview here (zipped mp3). (Firefox users- there is an audio player here, but it’s displaying intermittently. Trying to track down the issue. In the meantime you can download the episode or open the page in another browser).

Marom Bikson

Marom Bikson

(We got a good forty minutes of interview in before the Skype gremlins caught up with us. I had to cobble an ending together.)

Show Notes:
Post-Doc, Neurophysiology Unit, University of Birmingham Medical School, U.K., 2003
Ph.D., Biomedical Engineering, Case Western Reserve University Cleveland, OH, 2000
B.S., Biomedical Engineering (EE Concentration), Johns Hopkins University, Baltimore, MD, 1995
Introduction to Transcranial Direct Current Stimulation (tDCS) in Neuropsychiatric Research
5th International Conference on Non-invasive Brain Stimulation 2013

Instrumentation – making medical gizmos, process.
IRB- Institutional Review Board
IRB at the FDA
Small Business Technology Transfer STTR grant.

Soterix partners
Abhishek Datta CTO,
Lucas Parra
Bootstrapped at this point.

Difficulty in engineering medical devices is in designing for the anomalous cases- how that 1 in 999 times situation could go wrong.

Clinical trials. Depression, (Colleen Loo, Blackdog Institute), pain, stroke, epilepsy clinical trials ongoing.

Customizing technologies to match needs of particular clinical situations.

Soterix developed software designed for clinicians.
HDTargeting
HDExplore
Modeling current flow through the head.

Perhaps depression studies are closest to FDA qualification for tDCS?
(Prediction is very hard, especially about the future – Yogi Berra.)

A device (NorDoc Smartstim) that can go to 4mA is being used in a smoking cessation trial? (Trial info indicates 2mA current dose.)

FDA tDCS approval would be device-specific at first.  But would open the door to ‘me too’ mechanism, FDA 510(k)

HD tDCS can have multiple cathodes and or multiple anodes. An array of 4 small anodes splitting 2mA, for example (.5 mA each electrode), can function as an anodal ‘virtual pad’. Assumes cathode somewhere else on the body).

Image By Richard McKinley USAF

Image By Richard McKinley USAF

Tolerability is how tolerable in terms of side effects a medication is.

Transcutaneous Spinal Direct Current Stimulation Example tsDCS paper.

A Theory of tDCS (“Gross oversimplification”) As positive current flows into the cortex it passes neurons.
Because of the nature of neurons, this positive current depolarizes somas (cell’s body), increasing excitability, thereby increasing the functionality & plasticity of that region (hypothesis… “We really don’t know.”). Under the cathode, somas (cells) are being hyper-polarized – excitabilty decreases.

A synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another cell.
Pyramidal neuron

Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of an identified analyte.

TES Transcranial Electric Stimulation
“transcranial electrical stimulation” Merton and Morton 1980

“Priming the network in conjunction with applying tDCS makes a lot of sense, as a way to make the tDCS to do what you want.” (Co-priming – The idea that one would initiate an activity first, and THEN add tDCS.)

DARPA supported accelerated learning.

Memory consolidation.
Lisa Marshall

H. Branch Coslett, MD

DIY tDCS community and building medical devices. Redundancy.
tDCS implies proven, vetted protocols, that have been used in clinical trials.

Thanks Marom!

Dr. Jim Fugedy of the Brain Stimulation Clinic in Atlanta – DIY tDCS Podcast #2

[Apologies for audio quality. It won’t happen again.]

Dr. Jim Fugedy runs the Brain Stimulation Clinic, in Atlanta, GA, and has been treating patients using tDCS since 2007. Download the interview here (zipped mp3).

Dr. Jim Fugedy

Dr. Jim Fugedy

The Brain Stimulation Clinic in Atlanta is the destination for memory and learning enhancement and treatment-resistant patients who suffer from chronic pain, fibromyalgia, migraine headaches, CRPS, depression and tinnitus. Transcranial direct current stimulation (tDCS) therapy is provided in a pleasant, relaxing environment. Instruction, training and supervision for home use is also available for select patients.

Show Notes:
Jim is an anesthesiologist.
The study Jim refers to regarding Felipe Fregni & fibromyalgia:
A randomized, sham-controlled, proof of principle study of transcranial direct current stimulation for the treatment of pain in fibromyalgia (full pdf)
tDCS for treatment of fibromyalgia is not certified – it’s ‘off label’
Device is certified, but not for tDCS = no insurance code, can’t be billed to insurance
20 minute treatment for 5 days.
For fibromyalgia – reduces pain, improves issues – fatigue, compromised mental function
2″ electrodes
(ActivaDose ii Update 3/16 now available as complete tDCS kit through Caputron Medical, use voucher code ‘diytdcs’ for generous discount.)
Most benefit… chronic depression, treatment protocol based on Colleen Loo, Black Dog Institute 6 weeks, follow up maintenance. Up to 8 weeks of treatment + 1-2 treatments follow up maintenance.  Daily 20 minute sessions
Can be treated at the clinic for 1-2 weeks. Or home treatment package.
“To treat depression, I place the anode over the left dlpfc (left dorsolateral prefrontal cortex) and the cathode over the contralateral supraorbital area. I have tried positioning the cathode over the contralateral dlpfc and extracephalically (opposite shoulder or upper arm), but the contralateral supraorbital locations provides the most robust effect.” (Correspondence)
Pain montage 2mA, anode M1 & cathode contralateral supra-orbital area

A-M1-C-contralateral-supraorbital

anode at the right primary motor cortex (M1)–cathode on the left supra-orbital From: http://www.sciencedirect.com/science/article/pii/S1053811907000055

For chronic pain, the M1 is the most used area and that’s almost always my first choice.  But you can use the cathode over the somatosensory (S1) cortex, to down-regulate the patient’s perception of pain.
And you can also stimulate the Dorsalateral prefrontal cortex which is involved in the emotional component of pain.
Looking at stimulating right dorsalateral prefrontal cortex to attenuate anxiety.
… it may be a location
for the non-pharmaceutical treatment for ADD.
Office visit $150.
Home use treatment package $2400 includes in-office evaluation and training, ActivaDose ii device, electrodes, and unlimited follow-up via visit,  phone, skype…
Only side effect Jim has seen is skin burn (but easily avoided with sponge electrodes).
(Patient with skin burns who’d been treated by a doctor using electroencephalogram (EEG) electrodes.)
Tinnitus responds well, though temporarily, to tDCS
Anode, right dorsalateral prefrontal cortex, cortex opposite supra-orbital
Harvard one day course on how to treat with tDCS. Taught 3-4 times a year.
Contrast with approved Electromagnetic treatment for depression (I think he’s referring to TMS transcranial magnetic stimulation here) A 6 week 30 treatment protocol costs between $10-15,000. Affects last about 6 months. And even though it’s certified, it’s not covered by insurance.
…”in the 12 years that it’s been used there have been no side effects reported other than skin (irritations).
“You know we hear stories about Canadians having to wait for surgery. But in the United States, if you don’t have the money and you don’t have insurance,  you don’t have to worry about waiting, you won’t get the surgery.”

You can reach Jim at: doctorfugedy [theAtSignHere] transcranialbrainstimulation.com
Thanks Jim!

Ana Maiques of Neuroelectrics – DIY tDCS Podcast # 1

Well here we go! Episode one of the DIY tDCS podcast. Ana Maiques is co-founder (with Giulio Ruffini) of Spanish-based Starlab. Their spin-off company, Neuroelectrics makes Enobio, a research-quality wireless EEG device, and Starstim, a multi-channel wireless tcs & tDCS device. Download the interview here (zipped mp3). Show notes after the fold.

Ana Maiques of Starlab and Enobio

Ana Maiques of Starlab and Enobio

Ana Maiques wearing her Enobio

Ana Maiques wearing her Enobio

(If you speak Spanish you might enjoy the interview these photos were taken from.) Also, if you’re an EEG or tDCS researcher or clinician (or VC) on the East Coast, Ana is frequently in the New York and Boston area and is happy to discuss Enobio and Starstim. Neuroelectrics will be at the Advances in Mediation Research conference in NY Jan. 17 2013. (Schedule)  Check out the Neuroelectrics blog for excellent tDCS and EEG info.

Show Notes
Starlab is the parent company > Space (sensors) + Neuroscience
Cutting edge research > impact on society… products and services
Twelve years of research in neuroscience > Enobio, Starstim
Initial market is early adopters – researchers, clinicians and practitioners
Starstim (tDCS) > chronic pain, stroke rehabilitation (later… depression >> cognitive enhancement, addiction)
Medically certified in Europe and Canada
Filing 510k for Enobio in the US
Starstim has 8 channels for use as HD tDCS but can also use traditionally
Can also do tACS (alternating current), or random noise stimulation and at the same time Simultaneously record EEG
Can also use dry EEG electrodes
Roi Cohen Kadosh Oxford study, kids etc. (Link to video we discussed. NewScientist)
Study will determine if tDCS is efficacious in enhancing performance in certain areas (math)
Will have implications for people with Alzheimers
Partnerships with 15 hospitals doing research with Starstim
8 in U.S. and 7 in Europe. Different pathologies. Results to be published soon.
Post-stroke rehabilitation is a great place to see the effectiveness of tDCS
tDCS > Motor recovery… hand rehabilitation…
Can thereby measure the degrees of movement and improvement very objectively
Couple of groups showing very measurable results.
The Muse, Neurosky, Emotiv Home EEG devices?
Limitation is number of channels.
Started Enobio with 4 channels, but feedback from medical community lead to  developing a 20 channel Enobio.
For certain applications – games, BCI etc, the home EEG devices might be fine
But we’re looking at the medical application of EEG.
Doctors and researchers require the maximum coverage of the head.
Signal quality is very important.
EEG application
Emotion recognition, neural marketing, traumatic brain injury – concussion
BCI – wheelchairs.
Sponsoring a conference in NY on meditation. Sloan Kettering pre-chemo
medications >> less pain, better toleration of treatment.
Spanish VCs even more conservative since crisis
Patents >> cloud-based database recording experimental data
Software runs on a Mac.
We always said we want to be the Apple of neuroscience…”

Neuroelectrics Starstim

Starstim tDCS

Neuroelectrics Enobio

Enobio EEG

NIBS Non-Invasive Brain Stimulation – The Air Force Research Laboratory and tDCS

NIBS Non-Invasive Brain Stimulation

Every military application of tDCS I’ve seen so far specifically mentions drones and drone pilot training. This logo has a drone in it! For the record, I think the use of drones is illegal and immoral, and that the deaths of innocents is un-American and unacceptable. That said, the tDCS research coming out of this sector is fascinating and will no doubt have an impact beyond military training.

[Update 7/30/14 I’ve replaced the old (broken) link with an active one that comes via Ryan (see comment below)] http://colonyofcommodus.files.wordpress.com/2013/02/2012-afosr-review-mckinley.pdf it was a public document. It appears to be a set of slides used in a presentation. It documents the most aggressive use of tDCS for the purpose of learning and cognitive enhancement I’ve seen. You will conclude, after reading this, that the Air Force is not fooling around.

Air Force Research Laboratory Skill Learning tDCS

Here is one of the more shocking aspects of the research: The notion that cathodal stimulation can have a positive effect by depressing ‘competing memory’. What? The plot thickens.

Air Force Research Laboratory Skill Learning tDCS

There is weeks of research ahead for anyone diving deeply into this paper. A lot of new questions to answer.

Is tDCS Safe? – Neuroelectrics.com

This comes to us via the Neuroelectrics.com blog. I’m very excited to see Neuroelectrics on the scene. I first noticed their device Starstim (pictured),  popping up in news around Roi Cohen Kadish’s ongoing tDCS trials at his Oxford lab (see). I believe Neuroelectrics is a Spanish company. What’s especially exciting to me is that they also make an EEG device called Enobio and are working on the ability to map brain activity with EEG while undergoing tDCS. Think about that! Live, in-the-moment feedback on exactly what effect your tDCS is having.

More than 100 studies have been performed using tDCS in healthy controls and in patient populations, and no serious side effects have occurred for a review, see Nitsche and others 2008. Slight itching under the electrode, headache, fatigue, and nausea have been described in a minority of cases in a series of more than 550 subjects Poreisz and others 2007. Detailed studies have been performed to assess the safety of tDCS. These have shown that there was no evidence of neuronal damage as assessed by serum neuron-specific enolase after application of a 1 mA anodal current for 13 minutes Nitsche and Paulus 2001; Nitsche, Nitsche, and others 2003 or MRI measures of edema using contrast-enhanced and diffusion-weighted MRI measures after application of a 1 mA current for 13 minutes anodal or 9 minutes cathodal; Nitsche, Niehaus, and others 2004 […] In addition, a recent study was performed in rats using an epicranial electrode montage designed to be similar to that used in tDCS Liebetanz and others 2009. This demonstrated that brain lesions occurred only at current densities greater than 1429 mA/cm2 applied for durations longer than 10 minutes. In standard tDCS protocols in humans, a current density of approximately 0.05 mA/cm2 is produced.

More about the Neuroelectrics Enobio EEG device.

via Is tDCS Safe?.

Dr. Vince Clark University of New Mexico

[Update 10/19] Dr. Clark’s TEDxUNM just in. tDCS starts around 6:45

Dr. Clark is a pioneer of tDCS research. He recently spoke at TEDxUNM (TED talk at the University of New Mexico). I’m eagerly awaiting a video of his talk and will post it as soon as it becomes available. In the intro to Dr. Clark’s talk I found this amazing story.

You really need to read the full story. It outlines Dr. Clark’s journey to diagnose a rare disease that affected his 9 year old boy. tDCS is one of 3 treatment modalities he discussed in his talk…

Clark is already using tDCS to help treat drug addicts and reduce symp­toms in peo­ple with Parkinson’s dis­ease. As a part of this research, Clark is exam­in­ing the abil­ity to use tDCS to treat chronic pain, which he learned about while try­ing to find ways to reduce the amount of pain Ryan suf­fered.  He’s been col­lab­o­rat­ing with other research groups that are hav­ing suc­cess using this pro­ce­dure to reduce pain.

“It might be the first time that some­one has come up with a way to treat pain con­sis­tently, but with­out using a drug,” he added.

Update 10/1/12 Dr. Clark is involved in a new site which “is meant to offer information and links about medical alternatives that are cheaper, safer and more effective than the current standard of care.” SmallerMedicine.com (links to tDCS page).