Last month, the FDA held a public workshop on this topic. (I spoke on one of the panels, though I have no financial interests in these products.) Based on the discussion paper released ahead of the workshop, it seems that the agency intends to regulate these devices—it just hasn’t quite figured out how to do so. But although the FDA may have the expertise to regulate these devices, the idiosyncrasies of medical device law—namely, the complications regarding “intended use” claims—may not make this the best option, especially given the recent entrance to the market of devices that make no claims at all and instead bill themselves as “direct current sources.” The situation may require a novel solution—such as collaboration between the FDA and CPSC or the involvement of a third party, such as the National Academy of Medicine—to ensure the construction of a coherent framework that best encompasses devices on the market now and anticipates the complex issues that may arise in the future.
I had the pleasure of discussing tDCS with article-author Amy Dockser Marcus. She’s put together a very clear picture of where we’re at with DIY tDCS at the moment. I agree that Brent Williams is a great example of someone in the DIY community lighting the way towards safe and ethical home-use of tDCS.
I draw attention to this section of the article because it will be of special interest to regular readers. I find it very interesting to note that this letter addressed to “members of the DIY tDCS community” from concerned researchers happens to be under review for publication a few weeks prior to the FDA Workshop that will address the use of “non-invasive brain stimulation medical devices” (emphasis mine). Unless representatives from the likes of Focus, Thync or Halo Neuroscience show up to represent their devices, I think it very unlikely that the ‘DIY’ community will be represented (though Thync is certainly positioned apart from the DIY community there are obvious overlaps in interest). I signed up for the webcast. Assuming the webcast software actually works, I hope to observe a reasonable discussion between intelligent persons that finds nothing of note to be alarmed about.
Still, Dr. Hamilton believes some home users may not fully recognize that professional research in the field is largely done in people with brains “whose network has been altered and whose functions have been disturbed by or changed by injury.” Promising data gathered about neurostimulation on someone who has had a stroke, for instance, doesn’t necessarily apply to someone with “a normal intact system,” he says.
Researchers also haven’t studied possible long-term impacts of repeated use of tDCS by healthy people. There is some preliminary research raising potential concerns that when neurostimulation improves one brain function, there can be losses in other areas. Assessing the risks and benefits of the technology may differ depending on whether someone is healthy or ill.
Dr. Hamilton is one of a group of scientists and clinicians working with tDCS for medical applications who have written a letter aimed at members of the DIY tDCS community that raises some of their concerns. The letter is under review for publication by an academic journal.
I would only add that while Dr. Hamilton’s work with tDCS for the most part centers around aphasia (stroke) and pain, my sense of tDCS studies coming out of the science community is that it’s trending towards research with healthy individuals.
This is an incredibly well-researched paper. All the nuance of FDA regulation around tDCS and similar devices is made clear. I’ve been picking away at trying to understand this myself, but had become extremely frustrated by the complexity and opacity of FDA jargon and legalese. Anna has collected all the relevant facts and applied them very close to home citing specific devices and situations the DIY tDCS crowd will be familiar with. Anna Wexler is the author as well of The practices of do-it-yourself brain stimulation: implications for ethical considerations and regulatory proposals (gated) . She spoke to myself and at least a handful of other reddit.com/r/tDCS contributors for that paper. In both papers she lays out a very sensible approach to regulating tDCS, or rather, not regulating it. Stating that there is already a body of relevant law stemming from various government agencies (in the U.S.) that could be called upon to regulate tDCS device use as needed.
This paper contributes to the literature on the regulation of consumer brain stimulation devices in the USA by providing a fact-based analysis of the consumer tDCS market and relevant laws and regulations. In the first section, I present a short history of the DIY tDCS movement and the subsequent emergence of DTC devices. In the second and third sections, I outline the basics of FDA medical device regulation and discuss how the definition of a medical device—which focuses on the intended use of the device rather than its mechanism of action—is of paramount importance for discussions of consumer tDCS device regulation. I then discuss how both the FDA and the courts have understood the FDA’s jurisdiction over medical devices in cases where the meaning of ‘intended use’ has been challenged. In the fourth section, I analyse the only instance of tDCS regulatory action to date, in which the California Department of Public Health (CDPH) forced a firm to recall several hundred consumer tDCS devices. Although there exists a common perception that the FDA has not been involved with the regulation of consumer tDCS devices, the California case demonstrates that the CDPH’s actions were instigated by an FDA engineer. Finally, I discuss the multiple US authorities, other than the FDA, that can regulate consumer brain stimulation devices.
Marketing language from the websites of consumer tDCS devices available for purchase as of June 2015.
The focus of the second day of the workshop will be non-invasive brain stimulation medical devices, which are medical devices that are intended to improve, affect, or otherwise modify the cognitive function of a normal individual (i.e., without a treatment objective) by means of non-invasive electrical or electromagnetic stimulation to the head. The purpose of this workshop is to obtain public input and feedback on scientific, clinical, and regulatory considerations associated with medical devices for assessing and influencing cognitive function.
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 interviewhere (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).
(We got a good forty minutes of interview in before the Skype gremlins caught up with us. I had to cobble an ending together.)
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
Tolerability is how tolerable in terms of side effects a medication is.
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.)
I’m on the GoFlow mailing list and received this update this morning.
Hello all you beautiful peoples,
We’ve been silent for a few weeks now, and it’s time to bring you all up to speed on the GoFlow project again. (The diy tDCS kit if you’ve forgotten) We have officially been rejected from Kickstarter, and are delaying the production of our devices for a short while.
However we do have some progress to share with you all, and enough info to get anyone who is interested a decent way along in building your own. See below.
While it’s too bad that we are not able to rock a Kickstarter campaign, we move forward. During the process of getting the project ready for crowd funding we ran into a few legality concerns that probably would have stopped us from launching as quickly as we had planned, even if we were approved for Kickstarter.
We are taking the time to investigate these concerns now before we do something to prematurely sink our metaphorical ship. If any of you have any experience or thoughts that you’d like to share, we would love to hear from you.
Out main obstacles right now are:
FDA classification concerns
and subsequently approval
We’d love to hear from any of you that have experience with working with, and or around, the FDA. We’re talking to a few specialists and mentors now, but we are interested in leveraging the collective knowledge of you all as well.
We will keep you all updated to our progress as we move forward.