Monday, August 01, 2016
Readers Respond: tDCS ($) Versus TMS ($$$$)
Last week I devoted this space to discussing transcranial direct-current stimulation (tDCS), a much milder form of brain-zapping than electroconvulsive therapy (ECT), but nevertheless in the same category. Because there are not a lot of studies on tDCS, we do not have extensive statistical evidence that it does much good for conditions such as depression, but I asked readers who might have had experience with tDCS to respond, and two did: one amateur tDCS user and one doctor who trains and supervises patients to use tDCS. For reasons of medical confidentiality, their real names will not appear here, but for the purposes of this article I will call them Mr. P. and Dr. D.
Mr. P., a sufferer from depression, has been using a tDCS setup he built himself for about six months to help him during a transition from one drug regime to another. As to whether it works, he says, "I did experience a slight lightening of mood and a little more energy, and perhaps a more regular sleep pattern." But he admits that this is not a scientific controlled experiment, as he was also taking his medication at the time and could not therefore separate the effects of tDCS from what the drug was doing for him.
Dr. D. has assisted "patients using tDCS protocols intermittently with supervision to treat pathological conditions," including depression. He says it seems to be helpful in cases of depression that have proved to be resistant to other treatments. He "can't disagree when someone with this condition attempts tDCS. Considering the compromised quality of life, the potential improvement is worth the risk. Medical supervision would increase the success rate and make the procedure even safer."
Why isn't tDCS used more widely or studied more extensively? Dr. D. believes that "tDCS is not utilized primarily because of profitability. Transcranial magnetic stimulation (TMS) produces effects and results similar to tDCS. The cost of a 30-treatment protocol for depression costs $15,000 and re-treatments would need to be done at least yearly. And insurance is beginning to cover TMS." On the other hand, Dr. D. charges only $3,000 for a tDCS stimulator, training, and three years of supervision—a lifetime cost for tDCS, in other words, as opposed to the $15,000 each time a protocol of TMS is administered.
TMS uses a much more complicated piece of machinery than tDCS, a pulse generator that produces powerful magnetic fields which induce currents in the brain without the need for direct contact to the skin. From an engineering point of view, assuming the end result of small currents in the brain are more or less the same, the difference between tDCS and TMS is the difference between the old wired telephones ("POTS" or "plain old telephone service"), and wireless cellphones. Cellphones are a lot more complicated, but they have genuine advantages over wired phones. Whereas it may be that the only advantage TMS has over tDCS is that the machinery costs a lot more and the medical profession, speaking generally, can profit more from a treatment that involves an expensive machine or patented drug, than it can from a gizmo you can build with $30 of parts or a medication you can buy for ten bucks at a drug store without a prescription.
Fortunately, there are doctors such as Dr. D. around who help patients use less expensive and possibly more effective treatments, but you have to hunt for them. And as I noted in last week's article, the medical profession, at least that portion of it represented by the Annals of Neurology, has extended something of an olive branch to those who are using tDCS, rather than doing something obstructive such as calling for legislation to stop non-professionals from fooling with it.
Perhaps we can gain a little perspective on this matter if we ask a more basic question: what if the criteria by which we judge medical care are missing something important? Here's what I mean.
When we see two kinds of treatment being used for a class of medical conditions, and one costs mucho buckos and the other one is comparatively cheap, and they seem to do about the same amount of good, it's almost a no-brainer to ask, "Why don't we drop the expensive treatment and go to the cheaper one?" The answer comes back from the medical-scientific establishment: "Because we have studies that show the expensive treatment is effective, and we don't have anything like that for the cheap treatment." What is not stated in this interchange are the underlying assumptions shared by doctors, patients, researchers, and medical organizations.
One of these unstated assumptions is that for every perceived problem, there is a solution that can be discovered, researched, quantified, tested, and implemented efficiently and promptly. The unconscious image is that of a person in a supermarket, making a consumer's decision as to which technology to use. The philosopher George Parkin Grant, who made an appearance in this blog not too long ago, recognized that this technological outlook or perspective has become an almost automatic mode of thinking. In fact, it's hard not to think this way. He puts it succinctly: "Technology is the ontology of the age." And "ontology" is the study of being: what things really, fundamentally are.
What he's saying is that we tend to approach the world as though it were a big parts warehouse, or electronics showroom. Everything is there to be used, and everything is analyzed in terms of its parts and how they can be assembled to do something we want. Here's a person with depression. We treat him like a machine in need of repair. What will fix him? Certain chemicals? Expensive TMS treatments? Or inexpensive tDCS treatments? We don't stop to ask why he's depressed in the first place.
It's hard to imagine thinking in some other way, but in the space remaining I'll try. What if we look at a society in which more than one out of every ten adolescents in the U. S. suffer at least one episode of major depression per year? The technological fix is to look around for repair parts. But what if we looked into why being a teenager in this society is so gosh-awful depressing for so many? And the older they get, the more depressed they become, often. Try getting funding for that.
I'm glad Mr. P. is happy with his tDCS, and Dr. D. is helping others like him to get treatment at less cost than alternative treaments. But as for why so many people are depressed, well, that is, as they say in the technical journals, "outside the scope of this article."
Sources: I thank Mr. P. and Dr. D. for permission to quote from their emails. I was clued to the words of George Parkin Grant by a comment made by philosopher Antonio López on Vol. 130 of Ken Myers' excellent Mars Hill Audio Journal, a by-subscription podcast about which more can be found at https://marshillaudio.org. The Grant quotation itself is from his article "Thinking About Technology," Technology and Justice (Notre Dame Press, 1987), pp. 11-34, and can be downloaded at http://www.communio-icr.com/files/grant28-3.pdf. The statistic about the incidence of depression among adolescents is from the National Institute of Mental Health at http://www.nimh.nih.gov/health/statistics/prevalence/major-depression-among-adolescents.shtml.