Neurofeedback Rant


(start of rant)

After reading A Symphony in the Brain, by Jim Robbins, and Getting Rid of Ritalin, by Robert Hill and Eduardo Castro, I felt that neurofeedback training at home was a possiblity for me. I Googled, read, asked alot of questions, and started building an EEG system. I had a good start building the system (I had measured my ECG with it), and was ready to start looking into training protocols. While ordering some electrode paste online, I saw a book ADD The 20-Hour Solution by Steinberg and Othmer. The website stated, "The 20-Hour Solution explains everything that parents of children or adults with ADD or ADHD need to know about how neurofeedback techniques work." I mistakenly believed that meant exactly how it's done. Wrong. "Everthing... need to know" means "You can't do this yourself, you need to leave it up to the experts." You are an "expert" when you go through their training, so that you are then privileged to buy expensive equipment from them. I can say that it is expensive because I have designed my own EEG measurement hardware and software, and it doesn't cost that much to make. The material cost for the electronics is in tens of dollars (not hundreds or thousands). The more you look into this stuff, the more you find that the "experts" don't all agree. I'm not trying to totally slam Steinberg and Othmer; A Symphony in the Brain indicates that Othmer is a credible person who has genuinely contributed to the state-of-the-art in neurofeedback. It just irks me when those who at one time were experimenters just like me now call themselves the experts and discourage other experimenters.

Othmer states on page 111 of his book, "We emphatically caution against independently purchasing any of the variety of amateur biofeedback machines available on the market for as low as several hundred dollars. These... do not deliver... with the precision... of the high end professional models... only professionals can purchase the professional models, and there are good reasons for this.” (blah, blah, blah) Here I can speak. I am a registered Professional Engineer with 20 years of experience in circuit design (analog and digital). This is like saying, “You shouldn’t purchase amateur wrenches to work on your own car. Only professionals can buy professional wrenches, so you simply shouldn’t do it yourself with an amateur wrench.” Phooey. I can’t (any I won’t) endorse any of the inexpensive EEG units, simply because I haven’t used any of them. (I'm not going to spend even hundreds of dollars on something that I can make for tens of dollars.) But I have read the scientific literature to learn what is necessary to do this stuff, and there is nothing inherently expensive about making an EEG system of any sufficient quality. They are all basically the same: an instrumentation amplifier, a gain stage, a low pass filter, and an A/D converter. After that, it’s all software. (Unfortunately, software can be very expensive.) So maybe a professional unit boasts a 12 bit A/D, while the amateur unit (like mine) uses a 10 bit A/D. That might add a whopping $1.50 to the material cost. Whoo hoo. Why do I use 10 bits? It is all that is necessary for what I want to do. And on some of the commercial units, the specifications are just plain wrong. Some will spec the input impedance and CMMR (common mode rejection ratio) of their units with numbers taken from the datasheets of their instrumentation amps. You could call this wrong, or you could call this a lie. This is like measuring the top end speed of a automotive engine not connected to anything, and then claiming in the automobile sales brochure that the engine goes that speed. Is that misleading, wrong, or a lie? If there is someone out there who would like to defend any commercial unit on this point, email me with an explanation of the measurement setup and procedure for which some particular data is taken, and I will note the exception on this page. To be honest, I actually haven't looked at the specifications of many units (so maybe I shouldn't rant), but those that I have, the numbers match those of instrumentation amps. And not the minimum numbers either, but the typical numbers. This is either wrong, or a lie, depending on your point of view. From my point a view, that of an electrical engineer who has written specifications that were printed on a manual, it is a lie.

So, like working on a car, of course a professional can get the job done quicker. He has the right tools already on hand, and more importantly, he has done it before. But that doesn't proclude you from learning how and doing it yourself. The should be true for some forms of neurofeedback. And there is no reason that the home experimenter can't advance the state-of-the-art in areas that the clinicians haven't ventured yet. I know one individual involved with the OpenEEG-list who would love to be able to do neurofeedback to help his tinitis. Who knows that it can't be done?

(end of rant)

Back to EEG page