Dr. Dennis,
I am considering writing a research proposal involving use of the P9 device with the entrainment protocols and where treatment is EEG guided. In the “methods” section I will have to include a section listing the specifications of the P9 in terms of what is actually being delivered to the head–e.g., whatever the best biophysics metric is for communicating power/intensity range, amongst other parameters that should be communicated in methods section.
Dr. Sheldon Lewkis
I am open to following along with a home version n=1 study if this is of interest. I have a Muse S Athena headband (consumer 4 or 5 sensor EEG with FNIRS) and a P9.
A more detailed answer is plastered all over this forum in great detail.
Briefly:
Most important parameter is dB/dt, i.e. the time rate of change of the magnetic flux density. Generally I calibrate in the range of about 100 to 2000 kG/s, but this will depend on many factors mostly related to intensity setting and coil placement.
To know exactly what is being delivered for any specific use and any specific coil configuration, the only way to know is to set it up with accurate geometrical placement and realistic materials to interact with the magnetic pulses.
Of secondary importance is pulse duration. Generally by experiment I find that about 80 microseconds is the reliable minimum, and our systems are all programmed to deliver 100 microsecond rise times. This does not generally depend upon specific setup and use conditions.
Most reviewers of research proposals know absolutely nothing about these types of details, so from a grantsmanship perspective, you want to say as little as possible. Say too much and they will simply misunderstand, misinterpret, and then kill your proposal.
Yes, I have been to this rodeo many times and have the scars to prove it.
It is almost certainly best to just cite the information that we post about the products:
see pages 11 and 12 of the PDF.
If you feel that an accurate measurement under the specific experimental conditions is needed for the proposal, then I can make the measurement you need with a brief technical explanation. I will be happy to do so, but only if you first develop the proposal up to a ready-to-submit level of completeness, for which I will then generate the final required methodological text and measurements.
Bob, thanks for your response.
Is there some paper you can direct me to so that I can develop a comparative sense in clinical terms of the intensity of 100 to 2000 kG/s; for example, just how much smaller this is in magnitude compared to what rTMS units typically put out in terms of magnetic flux density (although their specs as commonly discussed typically site an output in Tesla units–typically around 1 T, rather than mag flux density). Does the magnetic flux density move between 100 to 2000 kG/s depending on the frequency being delivered and the intensity setting?
Sheldon
I don’t think there is a paper or simple explanation of that. It is the biophysics of electro-magnetism, and elsewhere in this forum I try to describe how incomprehensibly monumentally complex it is to try to understand electromagnetism. I’d say at most 5 or 6 people in all of human history have an intuitive sense for it. There is no easy way to explain it.
To help calibrate you to the complexity of this topic, think of the most nuanced and complex and poorly understood technical topic that you have ever encountered in your clinical experience.
Now, can you explain it simply and accurately in simple words in a sentence or two?
I’m guessing no.
Add to that the fact that PEMF is perhaps the least well studied topic in modern medicine, and is heavily stigmatized which prevents comprehensive research, and many other barriers to understanding the mechanisms, etc.
So, what are we left with?
First, if someone offers you a simple, and usually secret, explanation of the biophysical wonders of PEMF… they are trying to part you from your money. What I have seen for the past 3 decades: their “explanations” can be safely disregarded.
The best we can say is that when honest technical and clinical people study PEMF (or any topic) for decades, they collect many observations and see patterns and begin to draw reasonable summary conclusions, pending further observations.
Part of the reason, maybe most of the reason, why people ask about the mechanisms of action of PEMF is because of many decades of fraudulent marketing, where non-technical, and usually uneducated, marketers will stroke people’s egos to make them feel smart and informed and subsequently make a purchase.
Sometimes clinical people assert that “they can not recommend anything to their patients unless they can tell them exactly how and why it works.” This of course is nonsense. Just one example is the use of anaesthesia, which has been a great medical mystery for over 150 years, though it is used over 300 million times each year worldwide. Only very recently do we have a partial explanation for why anaesthesia might work.
I would go so far as to say that PEMF is similar in this regard: not well understood but clearly quite useful.
The best I can tell you after studying this for over 3 decades is that I have personally seen hundreds, and heard plausible reports of thousands, of cases where PEMF was seen to confer very valuable biological benefit.
Not all experts agree with me, but I see a very clear and repeatable pattern when applying various specific forms of PEMF, quite difficult to describe unless you have an advanced degree in physics or electrical engineering. I discuss this all over this forum, and am always happy to discuss it with anyone who has done the groundwork necessary to hold an intelligent conversation on the topic of bio-electro-magnetism.
Some people have told me that they find this insulting. I see it quite the opposite: I am not insulting people’s intelligence by telling them that one of the most complex and nuanced topics known to humanity is actually simple and they can pick it up from a few lines of text.
I think this is just one of those things where everyone needs to try to find an expert they can trust, and consider their advice.
I don’t ask Apple to tell me the details of how iPhone communication signals work, even though I do have the technical background to understand most of it I think. I think it’s just a great product, and I have used it for years. It’s not perfect, but I like it. Some people agree, and they tend to buy Apple iPhones, others do not.
For the people who have decided to trust me about PEMF, my advice, knowledge, and experience is baked into the details of Micro-Pulse ICES technology. It has enabled me to keep walking after a very bad back injury, and it seems to be very helpful for most people when they try it in the manner that I suggest.
What settings should you use, what is the explanation, clinical guidance, and so on?
I would follow the suggestions written all over this forum:
Start with default settings as delivered, start low and slow, Observe the reaction, adjust coil placement, intensity, duration, continue to observe and note (most people respond differently somewhat, no one-size-fits-all), expect to use the device 6 to 8 hours per day, every day. It may yield positive results in weeks, or just a few hours.
On the other hand, if you really do want to know the details of magnetic flux density, and the first time derivative of magnetic flux density (dB/dt) as it relates to biological and clinical effects, I discuss this in detail all over this forum. Just search the term “dB/dt” and read every post that I have made. That describes everything I know, the things I think I know, how my opinion has changed in light of further observations over the years, and my scientific hypotheses as to why it has the observed biological effects. That is a pretty good summary of what I have learned in the past three decades of work with the biological effects of PEMF, with occasional links to external resources.
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Thank for your reply Bob.
I experience a clear parallel in my own domain of expertise and as such what you have communicated to me is conceptually easy to comprehend. I decided to trust your expertise in applied biophysics when I ordered the device and my use of it is further supported that decision. However, as a clinician I have certain responsibilities ethically–beyond safe usage. These are really to know the basic technical specs (i.e., as should be reported in submitting for publication an article that uses the device–whether or not I’m actually submitting an article); knowing of any published or unpublished studies that use the device or similar device; having a very basic relevant conceptual technical knowledge, such as as if the frequency of the protocol is increased, does this imply that the intensity of the magnetic energy goes up or down within the operating range; and also what is the fraction of intensity of magnetic energy directed by your device compared to the most closely related clinically well accepted magnetic field technique of rTMS. This represents the needs of aware clinicians who are trying the do their job responsibly.
Sheldon
I think the best thing to tell potential clients is that “PEMF remains a largely experimental technology. Some PEMF devices have been approved by the FDA. Micro-Pulse ICES-PEMF has not been approved by the FDA”.
“Micro-Pulse ICES PEMF is based on Inductively-Coupled-Electrical-Stimulation, meaning that the end effect of the technology is an electrical field, not a magnetic field.”
“Micro-Pulse ICES PEMF was developed by Robert Dennis, PhD, to manage his own severe spine injury from a fire-rescue accident. The technology remains entirely experimental, no medical claims are made nor are any implied. The technology is available to individuals with the understanding that it remains entirely experimental with no claims or assurances.”
The technology is based on decades of research. The development has been mostly empirical and privately funded. There is no single or simple explanation of how or why it works. There is no single paper that can be referenced. ICES-PEMF is under continual development, subject to improvement and refinement. It is possible to formulate testable scientific hypotheses to elucidate underlying biophysical mechanisms, but these are currently not feasible due to a lack of existing scientific instrumentation to make the necessary measurements (single ion flux in paramembranous space - not trans-membranous ion flux).
The following is a description of the key electromagnetic parameters of ICES-PEMF, why they are what they are, how these parameters are currently understood, and important technical implications.
For those who are interested in knowing the basic parameters of how it functions at this point in its technical development, the scientific development of Micro-Pulse ICES PEMF is based on well-understood equations of electromagnetism plus a large number of prior scientific publications, observations, and experiments:
From the initial research at NASA-JSC for which I developed the TVEMF (PEMF) experimental system:
https://ntrs.nasa.gov/citations/20030075722
I later published more detailed methods and description of the pulse waveforms
https://www.josam.org/josam/article/view/5
From this research it was concluded that the key parameter causing detectable biological effects is dB/dt, as defined in Maxwell’s Equations of electromagnetism. The simplest presentation that I know of is presented here:
Of specific importance is Faraday’s Law of Induction, described here:
In differential form, these equations look simple, but when applied in practice to any real geometries, especially biological dimensions and geometries within living tissues, they are fiendishly complex and virtually unsolvable. Nonetheless, one of my doctoral students did make a heroic attempt to analyze the electromagnetic fields induced by PEMF in living tissues. His doctoral dissertation on this topic is available here:
https://cdr.lib.unc.edu/concern/dissertations/73666587t?locale=en
This is probably a bit much for the average person who just wants to know how ICES-PEMF works, but the first half of the technology really is this complex. But the good news is that this is the well-understood half of PEMF, and the take away message from all this work and electromagnetic theory is that we know for sure, 100%, that changing magnetic fields will induce a voltage, and this induced voltage will result in the flow of electrical current in a conductive material, which includes living tissue.
It is great to be absolutely certain about this, and this really is the only well-established technical aspect of PEMF in general. The remainder of the insight into technical details related to PEMF are mostly inference from several thousand publications, of highly variable quality, since about 1958.
First: Do electrical currents have any beneficial effects on tissues? Several good scientific papers were written on this topic ca. 1960-1970’s. These were able to show, usually, benefit from electrical current on bone tissue healing, as well as some soft tissues. But the exact electrical parameters used were often not well defined enough to describe them adequately, nor were the parameters varied enough to get a sense for “what ranges work and what ranges do not work”. Most of the electrical fields were applied by implanted electrodes, making these approaches mostly impractical. Some work was also done using induction (pulsed magnetic fields), not conduction (implanted electrodes). Comparing and combining this work requires some calculus and a lot of assumptions, but it does seem to indicate that this is the right general technical approach, and that PEMF would be far more effective and less harmful than implanted electrodes.
Since about 1958, a few thousand scientific papers were written on PEMF and related topics. Most of it amounted to small studies of low quality, a few case reports, some hypotheses based more on conjecture than real science.
Nonetheless, I reviewed the most relevant 660 papers. Aggregating all of that, and a series of experiments that I carried out at NASA-JSC, U-Michigan, MIT, and under contract with DARPA-DSO, as well as considerable and ongoing privately funded development, I was able to conclude that the effective range for dB/dt was somewhere in the range of about (this changed over time) 50 kG/s to 2 MG/s. Note, the physical units are “kG/s”, not “G” or Gauss. This is because the most important parameter is the time rate of change of magnetic flux density (dB/dt), not simply Gauss. An explanation of what these are and how they are related is given in the documents linked above.
With a reasonable understanding of the necessary shape of the pulse (the slope of the edges must be approximately in the range of dB/dt give above), the next key question is: How long is the pulse? (time duration of each pulse)
This is suggested by the classical physiological literature on “Chronaxie”:
I had done research on this topic for my work in tissue engineering:
It is crucial to understand that the values for Chronaxie are determined by experiment, not by calculation or theory. Based on classical physiology (a century old) and my own research using these parameters, I developed a series of experiments to determine the minimum effective pulse width for ICES-PEMF. To be very brief, the minimum pulse width for a pulse with the necessary dB/dt to reliably elicit a biological response is about 80 micro-seconds. To maximize reliability for response of various tissues I therefore set the pulse width to 100 micro-seconds.
I then patented and trade marked these two key parameters and other design details:
US_8029432
US_8137258
US_8137259
US_8376925
The ICES® Trademark indicates a device that employs these electromagnetic parameters.
Using these parameters, it is possible to calculate several useful results. For the determination of safety, for example, it might be of use to calculate the total electromagnetic energy being emitted by ICES-PEMF. Here is one example:
Using a 10Hz square waveform of any given peak Gauss level, what amount of energy is required, compared to an ICES-PEMF pulse of equal Gauss?
Answer: Micro-Pulse ICES-PEMF generates only 0.2% of the energy of a magnetically-equivalent 10 Hz magnetic square wave generated by a typical crude PEMF system. This means that crude square wave PEMF exposes tissues to 500 times more electromagnetic energy, but confers no detectable improvement in biological effect. Thus it could be said that ICES-PEMF is about 500 times more efficient than crude (typical) square wave PEMF, and as a result of the vastly reduced energy exposure, is very likely to be much less potentially harmful.
Another similar calculation can be made to compare ICES-PEMF to cranial TMS systems (that are FDA-approved)
The calculation is quite involved, so I’ll just give the answer that I calculated:
For the extreme case: ICES-PEMF at maximum power delivers less than 5% of the electromagnetic energy to tissues of the head than a normally-operating clinical TMS machine operating within regulatory guidelines to deliver a 110% to 120% MT (motor threshold) pulse.
So, briefly, ICES-PEMF delivers biological effects using a very small fraction of electromagnetic energy when compared to comparable electromagnetic technologies. To the extent that ICES-PEMF elicits a biological effect it does not do so by applying overwhelming power to tissues. The underlying biophysical mechanisms of action of ICES-PEMF therefore remain unknown. The parameters currently in use were developed as described above, and are experimental, and continue to be refined by Bob Dennis.
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Thanks Bob,
I really appreciate your response.
Do you think that the pulse duration you chose is suitable for use applied to the brain via the scalp?
Sheldon
It has been for me. See my reports on using it for stopping migraines. Others have had similar results. Also see another forum member’s post about using it on his mom who had late stage parkinsons.
yes, I think so. The pulse width I have selected (100 microseconds), based on my experiments, does seem to reliably elicit effects such as anti-inflammatory effects and beneficial effects for recovery of cognitive function following mTBI**, without causing muscle contraction or peripheral nerve depolarization (usually requires about 150-200 microseconds), and is definitely short enough to avoid interference with depolarization of cardiomyocytes (which usually requires ~1000 microsecond pulse width)
** Ref:
Tracking the effects of pulsed electro-magnetic field (PEMF) on individuals with a history of traumatic brain injury (TBI) with the Brain Gauge.
William Pawluk, MD, Robert Dennis, Ph.D., and Mark Tommerdahl, Ph.D.