It is sheer delight for me to just delve into Stephen Larsen’s new book and travel with him the remarkable journey of Len Ochs and his colleagues in the discovery and exploration of the LENS technique (which stands for Low Energy Neurofeedback System). No one could have ever predicted where the initial speculations might eventually lead. In retrospect, the journey represents an almost picture-book case of how clinical research should ideally be conducted. It may not look quite so ideal to those who actually went through it. The personal and financial crises that may have been strewn across the path along the way are mercifully not recounted. But the process can indeed be a model to the rest of us. There was no roadmap to follow. The process was willed forward by a very determined fellow, and yet he also flogged it with skepticism every step of the way. No one applied a more thorough-going critical eye than Len himself.

The initial speculations emerged out of Len’s collaboration with Harold Russell and his colleague Dr. Carter. They were making inroads on specific learning disabilities with some fairly generic audio-visual stimulation techniques at the time. The hope was to have a standard device that could be used inexpensively and across the board with lots of children. With the simple concept that one might be better off “responding” to the EEG with the stimulus rather than “driving” it open-loop, Len set out on a path that would take him to the very opposite terrain, namely toward a technique that is deployed under some fairly tight constraints and with highly individualized parameters, all done under the vigilant eye of an astute, experienced, and sensitive clinician, while taking on some of the most difficult challenges in mental health.The hope embodied in Len’s original speculation was more than realized. In fact, the very first thing that emerged was the observation that vulnerable nervous systems could be (too) highly responsive to EEG-following stimulation, and Len set about to moderate the impact in order to manage the outcomes. He surmised that the bad effects being seen along with good were matters of over-dosing. Reduction in stimulus intensity and stimulus duration followed. Len introduced “offsets” in the stimulus frequency to “dis-entrain” rather than “entrain” the EEG. In this dis-entrainment process the larger offsets had the more benign impacts. As one approached the actual dominant EEG frequency with smaller offsets, the effect was stronger, as might be expected.

Still, sensitive responders were over-dosing on the stimulation, according to Len’s observations. He reduced the light intensity further, eventually even taking the extreme step of putting black electrical tape over the light-emitting diodes so that no light at all could reach the subject. Still there was a response! Nearly every researcher on the planet would have left the trolley at that point, but Len persevered. People were still seeing clinically significant effects. Something had to be mediating the response.

It turns out to have been the electromagnetic signals from the LEDs that were cueing the brain in the absence of the light signal. So Len reduced the signal strength further by moving the LED glasses farther away from the subject. (It was about this time that I met with Len at an AAPB meeting in Denver to hear about his latest system. He held the glasses at arm’s length from me. He certainly gave the listener every possible excuse to just walk away.) Eventually he found himself holding the glasses across the room from the client, and still there was a response. It defied belief. No way could electromagnetic emissions from the glasses be affecting the client from across the room!

A further bit of detective work revealed that the stimulus was an artifact of the apparatus itself. The EEG signal was being processed with a DSP chip, and its megahertz signals were sneaking back up the EEG electrode wires right to the locus of interest on the scalp. Moreover, the amplitude of that radio-frequency signal was being modulated at the stimulus frequency. So the very signal that was needed just happened to be delivered to the very place where it was wanted. Good science often involves nothing more than recognizing an opportunity when nature presents it to us. No one in his right mind would have set this scheme up on purpose. The power involved? Something in the range of micro-micro-microwatts. It certainly invited incredulity.

What has since emerged is clearly the most “efficient” neurofeedback technique currently available to us for those who are responsive. (As with the other techniques, not everyone responds.) Len does not claim superiority for his technique in terms of clinical outcomes. Ultimately we are all limited by the brain plasticity that is actually available in an individual case. But the LENS technique does seem to provide the most rapid change for the clinician’s investment of time. And its relative advantage appears to lie with the more severe functional disturbances.

For the sake of getting on to other things I will give short shrift here to all the clinical and research data that Stephen Larsen reviews at length in the book, and which could by itself take up the rest of the newsletter. The compilation of reports and studies is utterly persuasive when regarded collectively.

Why, then, is everybody not already adopting this technique of doing neurofeedback? What keeps many clinicians from jumping aboard at once is the learning curve involved, and the drama that sometimes attends the work because of its unique power to alter brain function profoundly in such short order. Sometimes the best that can be done is just to give the brain time to sort itself out after a session. It is also easier for most clinicians just to navigate within the mainstream of neurofeedback rather than bivouac out on the frontier. And then we have the Red Queen principle: rapid progress in one’s own domain does not translate necessarily into relative advantage because everyone else is advancing also. We are all gaining on the problems of the brain in one way or another.

I’d like to go back and look again at the more basic issues of scientific research as they are illuminated by this example from our collective history. To a certain extent Len benefited from the existence of the neurofeedback community even though he also stood apart from it. Most of the people who came aboard the LENS approach had already taken the step of becoming part of the neurofeedback field. By the same token, the emergence of neurofeedback in the early nineties depended on the existence of the biofeedback field, even though the latter was never particularly hospitable to the new aspirant on the scene.

Ironically, those neurofeedback technologies that have the least connection to what may be called the “standard approach” have actually fared the best in some ways. Like currents in the river, those farthest away from our intellectual shores move more swiftly, less encumbered. Those approaches that aspire to evolutionary progress while remaining rooted in the standard models are subjected to more hazing because they are seen as defying orthodoxy. They stay closer to shore, and so are subject to more drag. Meanwhile, the more exotic modalities also remain somewhat unscathed early on because they are not yet seen as a threat. Nor do they besmirch the standard model.

By standing somewhat apart, the LENS technique helps us to clarify the issues in neurofeedback. First of all, it renders the placebo model inoperative as an explanation of our effectiveness. If in doubt about that, read the book; then let’s talk. Secondly, the approach disposes of the argument that volition needs to play a role. It can, of course, and probably does in much of our conventional neurofeedback. But efficacy is not contingent on the mobilization of intention or volition. It is not even dependent on awareness, contrary to much of traditional biofeedback. Finally, the LENS technique compels us to go beyond the operant conditioning model.

All of this has already become clear to us even in connection with our more conventional neurofeedback, but it is difficult for us to shed the ties to our past. Matters are left somewhat ambiguous in our case. With greater awareness, along with mobilized intention, on the part of our client, we do better than otherwise. It is then harder to argue that these attributes remain optional. We have also found it convenient to use the operant conditioning model to open the door to discussion in our training courses, and of course in connection with the research history. But then one also needs to move on, even though vestiges of the operant conditioning model carry forward. The LENS system dispenses with all these ambiguities, and we can say more persuasively now that what goes for the LENS system goes for us too.

The LENS system also illuminates the terrain between the physiological and the psychological domains. The very straightforward, rule-driven approach of brief stimulus-based training has similar profound consequences for emotional regulation to what we expect from our very different, carefully nuanced and meticulously optimized training. Empathy emerges either way. Yet the LENS technique will have accomplished this without explicit targeting of emotional networks, or concern with activity in the orbito-frontal cortex, or of deviations in a coherence matrix. It just follows its own rules.

The same goes for us. We just follow the rules that have emerged for our particular method, and self-regulation ensues. In each case, the rules relate to the process, not to the condition being addressed. One is prompted to ask what is the common element among all of these approaches? For this purpose, I prefer to look at the frequency-offset scheme in terms of phase rather than frequency. If one starts two signals out at the same phase, but they differ slightly in frequency, then one can also see this in the phase-plane as a gradual dephasing of one signal (the EEG at peak frequency) with respect to the other (the stimulus signal). Picture two clocks, with one set to run a little faster than the other. The two second hands, initially in lock-step, will gradually diverge. Similarly with the phase of the two EEG signals. The stimulus signal induces the brain to entrain with it, which looks like dis-entrainment with respect to the original EEG signal, and that also sets up countervailing forces as the brain resists such arbitrary interference in its affairs.

In other words, the LENS process is a challenge to the brain in the phase domain. That is of course also the way we now look at our inter-hemispheric or other bipolar training, and it is the way we understand the ROSHI. Whereas the ROSHI phase challenge occurs over a range of frequencies, and in our kind of neurofeedback occurs at a carefully chosen frequency, in the case of the LENS we are dealing with a brief impulse with respect to the dominant frequency. Since the LENS technique “works” with a variety of offset frequencies, the technique must be considered largely agnostic with respect to the offset frequency. And since the dominant frequency moves around, the specifics of the target frequency cannot be at issue either–it is not even consistent throughout the training session. What matters is the phase divergence, not the target frequency. A lower rate of phase divergence yields a stronger effect; a larger rate of phase divergence yields a lesser effect.

We can delineate this issue even more crisply by contrasting the above with the one principal approach in our field that does not rely on any such (continuous or episodic) challenge in the phase domain. It is the NeuroCarePro (NCP) system that, insofar as is known, works by event detection in that it withholds rewards for the largest and most rapid excursions in band amplitudes (as an index to variability). Because the system is transform-based (in its default operational mode), phase information on individual frequencies is not even available. Yet this approach too covers the clinical bases. This counter-example makes it clear that neurofeedback is not reducible to any singular pathway toward improved self-regulation.

For completeness we may also reflect on the differences between the phase challenge in the LENS system and in our steady-state approach. Sue points out that she gets distinctly stronger effects as the optimum reward frequency is approached. It is for that reason that the choice of optimum frequency may be so crucial. Those who work with fixed reward frequencies may never have an opportunity to encounter this effect. Engineers in our readership will recognize at once that we are high-lighting the characteristic of a resonant system: Phase varies most dramatically around the resonant frequency. If we are interacting with phase, then this parametric sensitivity is what we should expect.

We are seeking out a reward frequency on a functional criterion; hence our reward frequencies remain stable. By contrast, the LENS keys in on the momentarily dominant frequency. Both methods interact with resonant systems with common characteristics. One does so more dynamically; the other does so in an asymptotically stable manner. The two methods are natural complements. In fact, conventional neurofeedback has always combined a steady-state element (frequency-based training–the reward) and an episodic element (disregulation-detection–the inhibit). These aspects are naturally complementary, and that complementarity should carry forward.

The new book tells a rather complete, largely self-contained story, one that cannot be made to go away with the magic placebo wand. Larsen briefly reviews the historical antecedents in neurofeedback with genuine respect, then focuses on Len’s journey of discovery, development, and consolidation. The outcome upsets the applecart with respect to all of our favorite psychological or “medical” models of what actually goes on in neurofeedback. For a given EEG presentation, exactly the same procedure emerges for the LENS irrespective of what symptoms the client brings in the door. The same is true of the ROSHI. The default mode of NCP likewise takes no account of diagnostic distinctions. And in our own case, the starting procedures are largely independent of diagnosis as well. They do particularize to the person, but not in a manner that ties into diagnosis. We classify all such procedures as “non-prescriptive.”

So where does this leave us with respect to the “speciation” of neurofeedback at the present moment? One largely common element is the challenge in the phase domain, as already mentioned. This leaves out NCP. However, what the LENS and NCP have in common are that 1) both are EEG-responsive; 2) both are episodic in their intervention; and 3) both are non-prescriptive in their operation. It might even be said that NCP also subscribes to the principle enunciated by Len that “less is more,” because it certainly appeals to our brains with a very gentle and light touch. The induced functional changes just seem to somehow manifest over time, appearing without drama and without the awareness of much having happened along the way.

There is a clear trend toward neurofeedback becoming non-prescriptive in all of its manifestations. Even those who design their training to address QEEG anomalies are largely giving mere lip service to the underlying diagnosis. Any EEG anomaly to be targeted may be tethered formally to the diagnosis, as a kind of perfunctory and obligatory gesture to legitimize the intervention, but then matters proceed rather by their own rules, and it is the EEG that rules.

So where are we? Just as the speciation that took place in the Cambrian explosion can mostly be traced to the very earliest times in that epoch, it is likely that all of the major elements of a mature neurofeedback modality are already in view. Most likely the future will see mainly an elaboration and refinement of the existing approaches, as well as some considerable inter-breeding. (And prior to the impending merger and consolidation of technologies, clinicians are simply adding different systems to their toolbox.) So it is likely that the essential revolution here has already occurred, and it is not premature to celebrate it–all before the first NIH dollar was ever spent on neurofeedback in the modern era.

It is just becoming clear that the language in which we must understand this technique is more that of mathematics and neurophysiology than it is of psychology. The technique has to be understood at the brain level, where psychological concepts are of very little help. On the other hand, neither Len Ochs nor Stephen Larsen would have come to this point in their work except as psychologists. It was only as a psychologist in private practice, and navigating under the innocuous rubric of biofeedback, that Len was able to make an end-run around all of repetitive Transcranial Magnetic Stimulation (rTMS) research essentially single-handedly. The most dramatic breakthrough in mental health has all along been hiding in plain sight.

As for Stephen Larsen, what makes the book such a good read is the fact that it was written by a real Mensch, someone whose first orientation is to his patients in their full humanity, someone who is attuned to his own compass headings, who is not estranged from the ineffable in our existence. For him the LENS is merely an instrument in a much larger agenda of care. To be couched in that larger perspective, the book just had to be written by a psychologist. And indeed the book makes no attempt to come to terms with the LENS method in any mathematical formalism.

We are, in fact, getting to the heart of the mind-body problem here, as our neural networks mediate the interaction between psychological state, our thoughts and feelings, and our physiological states. It just so happens that our techniques operate at such a fundamental level, and the criteria of good function are so basic and universal, that good regulation can be achieved with reference only to the states of the system as we observe them in physiology, and with precious little concern about what the person sitting on top is thinking about or caring about or wishing for.

I cannot help but mention in this context that we have recently seen a certain back-sliding into the morass of psychological discourse, as people once again inquire about the nuances of operant conditioning that may be in play with neurofeedback. The problem is that in psychology these arguments never terminate with finality. The ghosts of all past controversies still journey among us, rattling our intellectual protective armor. The insistence that the problem must be regarded and resolved in a particular perspective brings to mind Jose Ortega y Gasset’s “learned ignoramus.” (“He is a person who is ignorant not in the fashion of an ignorant man, but with all the petulance of one who is learned in his own special line.”) I am looking to Stephen Larsen’s book to be the final deck-clearing operation that sweeps away all such sophistry. Here is a technique to which none of these considerations apply, and yet the technique covers nearly all the clinical bases. This ought to make it clear, once and for all, that the discussion about mechanisms does not have to be resolved within the framework of traditional psychology, and in fact it cannot be.

We are in a situation somewhat like that of plate tectonics, where doubters remained long after the science had become definitive. Stasis continued to be taken as a given even in the face of obvious plasticity. Those most soundly grounded in the old paradigm were least likely to observe that the world around them had changed. Stasis in geology was matched by stasis in the theory. Plasticity in the geology mandated the same for the theory. This is all very parallel to the issues we face in feedback. Historian of science Naomi Orestes recently reflected on the earlier history: “In any scientific community there are always some individuals who simply refuse to accept new ideas and evidence. This is especially true when the new evidence strikes at their core beliefs and values….” Orestes cited the example of Harold Jeffreys, distinguished Cambridge geophysicist, who opposed Alfred Wegener’s hypothesis of continental drift on the basis of its obvious physical impossibility when it was first proposed in the 1920’s. By the late sixties, however, we had discovered the mid-Atlantic ridge, so the theory of plate tectonics now had a perfectly viable mechanism. Moreover, we had also discovered the magnetic reversals, so our geologic history was effectively written out for us on the ocean floor. The acceptance of continental drift was essentially mandated by the evidence now in hand, and indeed plate tectonics became nearly universally accepted. Sir Jeffreys, however, “stubbornly refused to accept the new evidence, repeating his old arguments about the impossibility of the thing…. He died denying plate tectonics” [in 1989!]. “Those few who refuse to accept [the new model] are not ignorant, but they are stubborn. They are not unintelligent, but they are stuck on details that cloud the larger issue. Scientific communities include tortoises and hares, mavericks and mules…. Sir Jeffreys had become a scientific mule.”

So, a toast on this occasion to the maverick and contrarian-in-chief of our field, Len Ochs. (The mules, we understand, will always be with us.)And kudos to Stephen Larsen for the accomplishment of a superb book that chronicles the development of a technique that will revolutionize mental health care in general, hopefully displace the primitive and grotesque practice of electroshock sooner rather than later, and perhaps stay the revival of psychosurgery. A lot can be done with software, and it can even be done softly. One does not have to make sparks fly, and one does not have to throw out the motherboard.

Siegfried Othmer, PhD
drothmer.com

This entry was posted on Friday, August 18th, 2006 at 6:54 pm and is filed under Application of Neurofeedback, Books and Literature, Clinical Methods, Clinical Results. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.