Diamond Mind
Science, philosophy, spirituality, technology, green energy, current affairs. Hosted by scholar, activist and author, Tam Hunt.
Diamond Mind
Diamond Mind #4: Consciousness, Electromagnetic Fields, and Free Will with Prof. M. Bruce MacIver
Can electromagnetic fields illuminate the mysteries of consciousness and free will? Join us on The Diamond Mind Podcast as we explore this cutting edge question with Stanford Prof. M. Bruce MacIver, a leading expert in neurophysiology.
I sat down with Bruce at the Tucson Science of Consciousness conference this year, meeting for the first time in "real life" at that time. He and I have exchanged emails and Zoom calls for a few years now and he contributed a great paper to the Frontiers in Human neuroscience special issue on EM field theories of consciousness that I edited from 2020 to 2023.
We discuss the role EM fields play in brain function, potentially holding the key to our fastest cognitive processing and decision-making. Our guest also shares his career-long insights into the synaptic actions of anesthetics, particularly their effects on pyramidal cells in crucial brain regions like the hippocampus and neocortex.
Venture with us into the realm where the brain's electromagnetic field might be more than just a byproduct of neural activity, but a central player in cognitive processing. We dig into the historical and contemporary experiments that explore this intriguing possibility, considering how these fields might influence everything from athletic performance to the essence of free will.
Our conversation navigates through the brain's conductive environment, touching on cutting-edge technologies like transcranial magnetic stimulation (TMS) that hold potential for future breakthroughs in understanding consciousness and in neurotherapy as well as peak performance.
We also consider the impact of various substances, such as ketamine and nitrous oxide, on brain activity, revealing new insights that challenge old perceptions. Discover how these substances alter neural attractors and what that means for current and future research.
With a mix of scientific rigor and engaging storytelling, this episode offers a fresh perspective on how electromagnetic fields, myelination, and the dynamic complexity of the brain contribute to the ongoing exploration of consciousness.
Bruce offers a blend of intellect and intrigue that promises to expand your mind.
The Diamond Mind Podcast with the punches Exactly, keep on trucking as much as you can, but I guess let's start by looking at what you do as your primary area of research, so that's neurophysiology, electrophysiology.
Speaker 2:Mostly throughout my career it's been synaptic level, recording excitatory postsynaptic currents and inhibitory postsynaptic currents from neurons, mostly pyramidal cells and largely in hippocampal cortex, although in the last decade or so it was more neocortex. Basic electrophysiology of synaptic actions, of anesthetics, the goal being to first of all understand what it is that the anesthetics we're using now clinically are doing. How do they act? What sites are they acting at? With the idea being we can build better anesthetics devoid of side effects, which all anesthetics we're using now have, and, incidentally, the new grant is focused on exactly that. We've got a kind of pipeline of novel agents that we're going to be testing and developing.
Speaker 1:Is it small molecules.
Speaker 2:Yeah, small by small, like propofol, etomidate-sized molecules that incidentally bind to the same sites that etomidate and propofol bind to. On GABA receptors, but it turns out there are different flavors of GABA receptors. But it turns out there are different flavors of GABA receptors. I'm sure you know about GABA-A versus GABA-B.
Speaker 1:Vaguely, maybe say a word or two.
Speaker 2:GABA-A are the traditional ionotropic ligand-gated chloride channels. Gaba-b are metabotropic and they gate things like calcium ions, potassium ions, that sort of thing, and they work over a much slower time course. So GABA-B responses are in the hundreds of milliseconds to a second, whereas GABA-A responses are on the millisecond, typically 5 milliseconds A big difference, yeah, and out to 30 type milliseconds. It turns out there's different flavors of those channels Some that have very rapid decay, rapid onset, rapid decay, and they're called GABA-A fast and they're called GABA-A fast. Then the GABA-A slow channels are found at different synapses, physically separated, coming from different interneurons, and they last 20 to 30 milliseconds in duration. So for a couple decades now it had been. Ever since the GAaba a slow were first discovered, people started thinking oh, that's just the right time course for theta, whereas the gaba a fast are just the right time course for gamma oscillations in the brain. And more and more it's looking that's exactly the case today shut down selectively different frequency bands.
Speaker 2:Yeah, they're tuned to different frequency bands simply by the duration of inhibition. So the pyramidal cell fires. If it's only inhibited for a few milliseconds, then it's capable of firing again at the gamma frequency, and whereas the slows clamp them for 120 milliseconds, and so that's your theta.
Speaker 1:Yeah, that's the theta too.
Speaker 2:Periodicity.
Speaker 1:Are you looking at electroceuticals and the notion of using electricity or magnetism for anesthesia?
Speaker 2:I know there's some work on this over the decades, but it's not gone mainstream. No, we gave up on that. Back when I was a postdoc, my advisor and I were talking over beers and thinking if we could just pulse the brain at three hertz, we ought to be able to put people to sleep. And I think that's probably still true. So we figured can we do it with magnets? And we thought I don't know, let's go talk to the magnet experts. And at Stanford we have the Stanford Linear Accelerator and they're all about magnets for focusing beams and accelerating particles and stuff like that.
Speaker 2:So we went and talked to their engineering experts in the electromagnetic division and they said oh, sure, sure we could do that. Why don't you come on over and we'll try and put you to sleep? And we actually they.
Speaker 2:They said but we, we can't do more than a few inches yeah so we couldn't put your whole head in the magnetic field and we said, oh, a few inches, like about the size of a rat head. They said, yeah, yeah, we could probably do a rat head. So we grabbed some rats and went over to their research facility. So these are the magnets they're developing, they're experimenting with to get higher fluxes and better response times and stuff like that.
Speaker 2:And it was amazing, tam, the size of these magnets six feet long, five feet tall, solid iron, probably molybdenum yeah exotic metal and the power supplies used to drive these electromagnets were the size of a room, so half the size of this room was the power supply and the cables running out of the power supply to the magnets were submarine cables.
Speaker 2:Wow, transatlantic monster cables. We were like whoa, that ought to do the trick. So we took the rat and stuck it in the electromagnet and it was like we were on Star Trek. We were in the room and we start it up and we can start seeing the rat's hind legs twitching and we're thinking, oh, this is good and but we probably need to go a little higher. So let's turn it up. Scotty. Scotty's back in the power supply room going.
Speaker 1:Oh, captain she's gonna blow and sure enough, it blew oh, no way yeah, no smoke the rat or the magnet the power supplies driving the magnet yeah, uh smoke billowing out and daryl and I take our rat and go oh geez, we're sorry, oh don't worry.
Speaker 2:We were like maybe we can try it again and they said, yeah, we'll call you.
Speaker 1:We'll call you. Don't call us.
Speaker 2:So we gave that a try but weren't successful at it. Now, cleverer people have come up with better ways of doing that. To make an electromagnetic field alternate requires an immense amount of power because you have to tear down the magnetic field and rebuild it against itself on each cycle.
Speaker 1:Yeah.
Speaker 2:So hence the big submarine cables.
Speaker 1:Yeah.
Speaker 2:Tons of amps of power of amps of power.
Speaker 2:Now a better thing to do is to spin your subject in a fixed magnetic field or move your subject within a fixed magnetic field, because fixed magnetic fields are trivial, like MRI scanners, for example. And so there are guys. Now what's his name? Santosh helcar at he's in in houston, I don't know if it's baylor or I think it's baylor. Anyhow, he's done just that he's developed these very powerful fixed magnets that he can spin around the head of an individual, and I haven't talked to him lately, but he was saying that they're, they think they're going to be able to knock people out with it. Right now they can just make you dizzy, but we know from MRIs, for example, when you move people in and out of the field they'll report dizziness, nausea.
Speaker 1:There are certainly effects of the magnetic field of the brain, as you'd expect for a powerful magnet. What about TCDS or TACS? Those seem to be easier tools to use.
Speaker 2:Yeah, they are To induce a certain rhythm. Yeah, but there you're limited to pulses rather than a sine wave.
Speaker 1:And you think you need a sine wave to induce delta.
Speaker 2:I don't know, I'm thinking if you could do 3 hertz pulses out of work. So far no one's reported that. I think also it's so localized that you would have to have a cluster.
Speaker 1:And I guess some risk too if you were to use that kind of anesthesia. Let's say it was a power outage and you're mid-surgery.
Speaker 2:Oh, it's not going to be very happy, no, but they have power backup they have backup. Yeah, all the hospitals have on generators, yeah okay but there could be a moment or two where could be some issues. It could be problematic yeah, well then they just revert back to old school surgery, where everybody piles on the patient holds them down down.
Speaker 1:No way to do it. Whiskey.
Speaker 2:No, they didn't hardly ever even use whiskey, it was just a brute force. You hold them down while we saw his leg off.
Speaker 1:Oh yeah, that's not, that's a myth. Of the alcohol anesthesia.
Speaker 2:It was used a little bit hardly ever, because of to knock someone out with alcohol.
Speaker 1:You know how you feel after you've passed out on alcohol for at least a day and feeling pretty sketchy for a few days and especially if you're pouring the alcohol on enough to keep someone from twitching yeah, during a painful stimulus yeah, but to me, I think that's one miracle of modern medicine for sure is that we have effective anesthetics, because, like you said, it was not the case.
Speaker 2:Anesthesiologists will tell you that's the most important miracle of modern medicine, but they're biased, of course they're a little biased yeah.
Speaker 1:This is a good segue to the work I know best from you in terms of looking at this notion of EM field theories of consciousness, and you contributed a great paper to our research topic of frontiers.
Speaker 2:Well, it was a paper, it was a paper, it was a great paper, it was a great series, it was to the point.
Speaker 1:It was very effective, very focused and you were trying to basically take these old objections to EM field theories and say, actually maybe they're not so big objections after all. Could you speak to that a bit?
Speaker 2:Sure Early on. We're talking like the 1940s era. This idea that the brain generates a electromagnetic field was already known, because we already were recording EEG signals.
Speaker 2:From the 20s, right yeah, from the 20s, right, yeah, from the 20s. So people were thinking about this wow, we've got this field being generated by the brain, an electric field, at least at that stage, that we can record through the skull, so inch away from the surface of the brain. So that's a pretty decent field. And shortly thereafter, of course, it became an electromagnetic field, because you don't have current flow and only generate electric fields, you generate a magnetic field as well, the old rule of thumb law. So we knew that there were EM fields being generated by brains way back and people were proposing I forget the first guy who came up with it, german said that's, that could be the mind. That may very well be where the processing, cognition, consciousness, resides. It's in a field because that's capable of doing vastly more complicated computations than neural circuits will ever be able to do, and it does it at the speed of light. Very fast processing is capable.
Speaker 2:Which gets to these issues about how does a hockey goalie ever stop a puck come to slap, shot at him three, four feet in front of him and yet boom, he's got it. How does a batter hit a hundred mile an hour? Fastball when the timing doesn't quite work? Fastball when the timing doesn't quite work, it barely works. But there's no time in the middle for processing. Now they're highly trained baseball players, so they've got all the motor programs all lined up. So once they've figured out the trajectory, then there's not a lot of motor processing. Oh, how fast is the ball moving? Where is it going to be in space? And all this. You can just execute the pre-programmed cerebellar spinal circuit to do that.
Speaker 1:Yeah, it's queued up.
Speaker 2:And remember, if you've got a batting average of 50%, you're pretty good.
Speaker 1:Very good.
Speaker 2:So you're going to be missing a few anyhow.
Speaker 2:But anyhow it addresses those kinds of questions. How can we have these lightning fast reactions? Ping pong players, international Olympic level players you can barely see the ball, let alone get to the right place in the right time with the right motor program to put the right top spin. But an EM field, it can process like at the speed of light. It can do a lot of stuff in a millisecond, whereas neurons they barely get started in a millisecond. That's the quantal unit of brain. Communication is the action potential, and that's a millisecond. To cross a synapse is two to five milliseconds. And to do any kind of hierarchical processing, talking about crossing hundreds of synapses, even if it's a bunch of them, are in parallel. They're not all in parallel. There are a number that have to be serial and you run out of milliseconds in a hurry.
Speaker 2:So anyhow, that's always been in the back of my mind and and as a undergraduate, hanging around the door and talking philosophy Louis Hours, we were talking about stuff like this Couldn't the brain generate a field?
Speaker 2:That is the mind? And so that kind of sat in the back of my head for many years. But then, through reading your papers and others in the field, I said there are other people out there who are thinking the same way. And then I did a. When I saw the special issue that you headed up in Frontiers, I thought let me really delve into this, do some serious reading. And so I spent about a month going over the older literature and reading the new ideas and thought this is still very plausible, and the only issue was that in the 40s some really important neuroscientists like Sperry and Blanken on the old guys that were pioneers in electrophysiology they tested the theory by putting conductors like gold leaf on the surface of monkey cortex, the idea being that and then grounding those foils like a tinfoil cap kind of deal and that that should abolish the EMF at the shield.
Speaker 2:It'll just get absorbed.
Speaker 1:This is on top of the cortex in this experiment.
Speaker 2:Yeah, but then they also placed some depth electrodes, an array of depth electrodes, but there weren't a whole lot of them back then. If you had 10 electrodes that's a lot. But that didn't interfere with the monkey's ability to process visual information. So they were focused on the visual cortex at the back of the monkey brain and put these foils and or pin needles in to try to ground out any EMF, any local field potentials that were being generated by the cortical tissue. And monkeys were still quite capable of doing tasks they'd been trained to do. That involved the visual cortex. So you see a light and you reach for the banana kind of thing.
Speaker 2:But I got to thinking electric fields are bidirectional, they're multidirectional In 3D they're 360 degrees. So if you move open a channel in a nerve cell so current can flow into the nerve cell, that's going to radiate an electric field in three dimensions. And the top of the skull is a pretty good barrier to electromagnetic energy, even though we can still record through the skull, which tells you the fields are much stronger inside the skull than they are outside the skull. But they're not just radiating outwards like an aura from the brain, they radiate inwards as well. Think of it as cones focusing down towards the brainstem, involving thalamus and basal ganglia, everybody.
Speaker 2:All these EMFs are summing and influencing each other in the inside of your brain more so than on the outside, because on the outside it's dispersive, there they can't go very far there, but on the inside of the brain that's a perfect electrolyte media, salt water the your whole skull is full of salt water and a very excellent conductor for these current loops that every time an ion channel opens it generates a current loop, and those current loops are going to be able to penetrate much further into the brain than they are out of the brain, because out of the brain is just all insulator and nothing to conduct it. So I said, yeah, okay, so that's why those experiments didn't work.
Speaker 2:They were trying to block these weak fields on the surface of the cortex, when what they should have been doing was blocking the propagation of the electromagnetic fields into the brain internally. And that makes so much more sense from a philosophical point of view to the big, the hard problem, the binding problem, the, the. Where's the little guy inside your brain?
Speaker 1:There's the squirrel. Yeah, there. This morning I swear to the squirrel in my head. So that's's the squirrel. Are you there this morning? I swear there's a squirrel in my head so that's where the squirrel is.
Speaker 2:It's in these intermagnetic electromagnetic fields that are dancing around. They're very obviously complex, intertwined with each other. So your motor cortex knows immediately what your visual cortex is doing, just based on these field interactions in the center of your brain. Similarly, your brainstem knows what your visual cortex is doing instantaneously. You don't need five or six synapses to get back to it. They know that. And the homunculi, the central sulci in the human brain, has the sensory and motor cortices adjacent to each other and the homunculi are adjacent.
Speaker 2:So your finger motor is right next to your finger sensory. So a baseball player going to swing the bat, his motor cortex can be primed hundreds of milliseconds before any synaptic signals get over there, just because the visual cortex is primed.
Speaker 1:Have we measured this particular dynamic, comparing synaptic versus field effects?
Speaker 2:Yeah, there are several papers and more coming out more recently. The original work was Jay Miller out of UBC in Canada, vancouver. He and a couple of his grad students showed in a series of papers a couple papers really conclusive evidence for what are called ephaptic communications between neurons.
Speaker 1:In humans.
Speaker 2:No, this was actually in brain slices from rodents Got it? No, in humans, I don't know. Probably somebody has done something like that, but I'm not aware of it.
Speaker 1:It's tough to do in humans, as we all know.
Speaker 2:Yeah, but it's not that tough anymore. We've got a lot of patients now with indwelling electrodes Into patients.
Speaker 1:Yeah, almost always into electroplastic patients Almost exclusively.
Speaker 2:However, there are also Parkinson's patients with deep brain stimulating electrodes. There's now putting in deep brain stimulating electrodes into thalamus, into excuse me, into numerous subcortical nuclei to control, reverse, augment or diminish various undesirable features like tremor and Parkinson's. So the idea that the fields generated by a group of neurons like the best example, the ones that Jay Miller focused on were the theta rhythms in the hippocampus. Now the hippocampus is a monolayer cortex, it's got three layers, but a monolayer of pyramidal cells. They're all packed into one nice neat sheet with apical dendrites poking out one side and basal dendrites out the other, and they were able to show that theta fields could bring neurons that are already close to threshold and they would fire. That was the first physical demonstration that an electromagnetic field could influence the discharge of neurons, but now it's generally accepted.
Speaker 1:And that's the Chang et al 2019 paper right.
Speaker 2:That it's generally accepted.
Speaker 1:The one with the brain, slices from the amount of the mice from the case western reserve team.
Speaker 2:No, that's much later, jj miller's stuff was back in the 90s oh, okay, interesting, all right like 1990, 91, 92, but no other people have since clearly shown in spinal cord and cortex that ephaptic interactions are fully capable of either taking cells away from their discharge threshold or moving them towards and that's partly how these traveling waves that Earl Miller talked about the other day work.
Speaker 2:This group of cells depolarizes the adjacent group of cells and that's how these waves spread through cortical tissue. In fact, I think Earl thinks that's the main way that these traveling waves are directed through cortical tissue. So that gives you a closed loop, then a feedback loop, so your neurons generate the electric fields. The fields can interact with each other and then in turn interact with the neurons to determine whether they fire or don't fire.
Speaker 1:Because a dance is a two-way street. Yeah, it's a dialogue.
Speaker 2:And Earl's movies make it look like a dance as well.
Speaker 2:And you can envision a three-dimensional field inside your skull is constantly dancing because it's ever-changing. So much going on. These cells fire and that causes this and those cells fire. And it's not just cortical cells that are firing. All your brainstem nuclei, thalamus, all those deep cells show rhythms too. Now, whether those rhythms are driven by cortical rhythms or vice versa, we know vice versa for sure because we know the ascending cholinergic nuclei that all exhibit local theta rhythm that's in tune with the cortical theta rhythms from hippocampus and the cortex and that makes perfectly good sense in an awake behaving animal. But all these fields would be interacting with each other and helping to tune each other where does the, the enteric brain, fit in with this particular rhythm?
Speaker 1:you've got a 0.05 hertz. It's like one of the rhythms, the peristaltic rhythm in the gut, and there's definitely some evidence that shows some correlation between that rhythm and alpha rhythms in the brain. Do you see this as being? Pretty yeah it's interesting stuff. Yeah, it's not that well known yeah, certainly.
Speaker 2:I can well imagine that they would set some of the kind of default mode rhythms. So instead of a default network you've got default rhythms. The most important, I think, is going to be the heart, your pulse, because every time your heart beats your brain swells a little bit, and especially in the midline regions of the brain where the carotid arteries are coming in, you're going to have huge effects on any emf field just through pure volume changes. I certainly think the heart rhythm contributes a constant, ongoing drive to the brain magnetic emfs. I think I wouldn't be surprised if all the rhythms throughout our body can contribute in one way or another and that may set the baseline level of EMF energy upon which the neurons are first of all driven to activity and then have to in turn influence activity and then have to, in turn, influence.
Speaker 1:Yeah, so I've been thinking about this notion of the spike code in relation to what I'm calling now the field code, and I guess you were there when I asked earl this question. If you have good data showing that the fabric field effects are, let's say, 5 000 times faster which is, I think, right than the most synaptic transmission, which is about 100 meters per second, that is fastest, as low as 2 meters for some. So if you're at 5,000 times the velocity for these field effects and you volumize, that's a whole lot of additional data that you can. Or, if you want to call it data causal influence in that field effect versus the traditional synaptic field effects. Does that make sense to you that?
Speaker 2:framing. It totally makes sense to me. I don't think Earl caught that at all.
Speaker 1:Yeah.
Speaker 2:Although he is so close to, he's just one step away from the theory of the mind. I just don't think he's very much aware. In fact, I know he wasn't because I emailed him right after that session. And I sent him your paper, my paper, and said you are just bumping right up against this old theory of mind, of cognition, called the electromagnetic field theory. And he wasn't aware of that no, he wrote me back and very interesting wow, that's very interesting.
Speaker 2:Those were his words yeah, okay so whether he'll continue down that thought stream, because he was already talking about the closed loop between the field and the neurons? Yeah, and how that that can depolarize the next group of cells through a phaptic field interactions? So, he's right there. He just needed to go one step further and say, okay, so the EMF actually is the mind. That's my working hypothesis it's going to take a lot of convincing to prove that's not the case as far as I'm concerned.
Speaker 1:Is this a new view for you in the last few years?
Speaker 2:No, I told you back as an undergraduate. These kind of ideas were popping off among our friends in the dorm.
Speaker 1:Was that the view you held personally, or you just knew about it? When did you come around to thinking this is maybe probably the view we view we should hold?
Speaker 2:to be honest, I didn't really hold any views. It was agnostic as to all of the theories of mind and consciousness because I thought there's no good evidence to support anything at this point I'm a nihilist, yeah and I'm still pretty much in that camp because we really don't have the kind of rock-solid evidence we need Now. If we can start pulsing and perturbing the magnetic EM field in constructive, interesting ways, then that's really going to be the evidence we need to show. That's quite plausible.
Speaker 2:It's already plausible, but to prove that's quite plausible. It's already plausible, but to prove that is an important feature yeah already we know we can tweak the emf and make you jerk your finger yeah, stuff like that knock you out temporarily the tms, I think yeah, I don't know about knock out with tms partially knock them out yeah, you can certainly alter mood and stuff like that, which is depending on what parts of the brain and not just with magnetic fields, but also ultrasound, vibrational, mechanical energies can mess around, which makes sense too, because anything you do mechanically to the brain tissue will impact the EMF.
Speaker 2:Yeah, there's no way around it.
Speaker 1:Yeah, it's a gestalt right. It's one thing. How does it wiggle right?
Speaker 1:Yeah, it's like a jello, you poke it and it's going to and I guess this goes to the question I was asking, earl, of the frequency of the wiggles in the jello model If the base of that jello is wiggling at five to eight hertz, if the base of that jello is wiggling at 5 to 8 hertz but the crown of the jello is wiggling at 1,000 hertz, there's clearly a whole lot more information content in that higher level wiggle, right Sure. So if you take that idea and say, okay, this is maybe where the real game is being played, what does that render the causal function of those lower level firings, those synaptic firings? Is it rather than like an energetic substrate only, or do they have their own role, their own level? But then there's so much more going on above that level.
Speaker 2:Oh no, they're absolutely critical for carrying out most of the business work of the brain. So all the behavior has to come out through motor cortex, lower brainstem motor nuclei cerebellum out through the spinal cord, all synaptically, Although there's no reason to think that the EMF can't penetrate all the way down the spine, but it's going to be much weaker.
Speaker 2:It rolls off very dramatically with distance. But we also know that you sever the spinal cord and that's it for movement. Yeah, it doesn't matter how much EMF is getting through. Yeah, that's a good point. You're paralyzed and same for sensation. So they're involved in the business. The working parts of sensory perception and motor output, for sure, and breathing and all that other stuff, keeping our heart at the right frequency and the right force of contraction to pump the blood that we need. All of that kind of stuff is critically dependent on action potentials and synapses. But the stuff about free will, oh, I think I'll move my hand. That's not coming from synapses and neurons, that's coming from a cloud of energy, that's the mind. And the only viable cloud of energy around in our skull are. There's emfs, but there's also photonic, a lot of photonic energy bouncing around you would see that as being distinct from the traditionally emfs no, because it's another another form of emf right exactly
Speaker 2:yeah there's a guy up in calgary, the head of the physics department there. He's got a couple of cool papers on how photonic energy could be integrated into EMFs to contribute to a mind. What's his name? Yeah, I knew you were going to ask me.
Speaker 1:Hard questions, Calgary okay. Hard questions, Calgary okay.
Speaker 2:Just you know. Google photonic transmission in the brain.
Speaker 1:Is it biophotons? It's a general area.
Speaker 2:Yeah, they're generated from mitochondria, it turns out that was really quite an interesting mystery. Do we know why they do that? Yeah, it's part of the electron transport chain. So as you send energy down the chain, you emit a photon at certain stages before you.
Speaker 1:ultimately start producing ATP or whatever. Ah, yeah, yeah, okay, so it's a biochemical process. Is it a signaling process, though, or do you think it's just an epiphenomenon of the other underlying process?
Speaker 2:It's a good question. I would bet that it's dual purpose.
Speaker 1:Like most things in biology, right Mother Nature doesn't waste. Yeah, she's very efficient.
Speaker 2:Yeah, she's going to if she can use it in a constructive way. It's going to be used that way.
Speaker 1:I want to ask you about this intriguing notion you just raised of the notion of choice and free will. So when I raise my arm, the motor neurons are doing the actual signaling to move the muscles to raise my arm. You're suggesting that the higher order spatial, temporal structure, that is the EM field of our brain, that's where the ideation and the possibility kind of mapping takes place and then a choice is made that then goes down to the motor neuron and the choice is made.
Speaker 2:Exactly, the choice is made. That then goes down to the motor neuron and the choice is made exactly, okay. Emf talks to not just motor cortex but the whole inside of your skull and says I've got an idea. I'm going to move your finger, and so what?
Speaker 1:do you think about that?
Speaker 2:sensory cortex says sir, yes, sir, motor cortex jumps in line and they all put together the circuits they need to get the job done.
Speaker 1:Yeah.
Speaker 2:Yeah, there's an interesting colleague of mine at Stanford, robert Sapolsky, who came out with a book just recently about that. There is no free will.
Speaker 1:It's a common view nowadays. Yeah yeah, I choose to not believe those people.
Speaker 2:No, exactly Because it just doesn't feel right and he has no explanation for where volition comes from or even the feeling of volition yeah, boom, I just decided to pick up my glasses only, uh, because my mind needed something to demonstrate, uh, free will.
Speaker 2:But there is something that's that's running the ship. There's a pilot in the pilot house, um, that's saying, okay, you pay attention to this or you don't, and and I think there is a consciousness and it is an energy field. That's what makes us conscious. Yeah, when you have enough stuff together, it's like the iit you got to have enough stuff for complexity. But once you've got a complex enough brain, then you, you're making complex enough emfs to be conscious.
Speaker 1:Not see a threshold being needed for that like what? No, it's a continuum okay, yeah, it's.
Speaker 2:There's probably consciousness down in all life forms and, some people would argue, in inanimate entities in the field of self, no matter how simple or complex. Yeah, but the more complex things are, the better the consciousness, because we can start writing poems and we can start writing philosophy textbooks and thought and stuff like that. Indeed, is there a threshold for that? It looks like it's basically the human brain, because the other primates don't do that don't do what the complex language, etc.
Speaker 1:But you're not saying they're not conscious. You're saying they're not as interesting as we are.
Speaker 2:They're not as complex as we are, complex enough to generate an EMF that can come up with these kind of new ideas. Not that crows come up with new ideas but, come up with the kind of complex ideas that we have about consciousness and self and and will and motivation and dogs. They don't think about any of that stuff, they're just. What are we going to do? What are we going to do now?
Speaker 1:exactly where does that come from? We've been looking a bit at the role of myelination in higher order, basically in neocortical development. Of course vertebrates have myelination, invertebrates don't. Dogs do have myelination, and yet they clearly are complex is what you're saying.
Speaker 2:They're not as cognitive as we are, but they're highly cognitive.
Speaker 1:Yeah, they're like an infant in many ways, they can understand commands et cetera, but Like an infant in many ways they can understand commands et cetera. But yeah, I think you're right, they're probably not composing poetry. But that role of myelination in terms of the evolution of these more complex systems that we call mammal brains et cetera, or vertebrate brains more generally, vertebrate neurons more generally, do you see just a constant arc of evolutionary innovations that got us to this point, or are there like step changes?
Speaker 2:I think the development of neocortex is is a key, fundamental change and especially of a you know all the sulci and gyri that go into the human brain and dolphins and whales.
Speaker 2:That allows these ephaptic interactions to occur way more often. So the enfolding of the cortical sheet really was an important component to this because it allowed a lot more intricate, intimate interactions between otherwise unrelated neurons like sensory neurons and motor neurons on the central cell side. So I think that's key. Myelin, that's all about just speed of transmission. So that's a. You can see that as just a real evolutionary advantage. If you can detect signals quicker and move faster, that's better. And in order to detect and move you've got to have axonal signaling and myelination just dramatically speeds up and myelination just dramatically speeds up signaling. For example, some of my early work was in pain fibers A, deltas and C fibers. C fibers sense things like cold and chemical irritants, which are slow stimuli, whereas A, deltas and they're unmyelinated. They're small diameter unmyelinated fibers. A delta fibers sense pinprick and burn and things that you've got to know about in a hurry.
Speaker 1:They're not myelinated. No the A deltas are myelinated.
Speaker 2:They're the first neuron types to become myelinated.
Speaker 1:And ontogeny, yeah, okay.
Speaker 2:Yeah, and developmentally as well, yeah. Okay, that's just an evolutionary advantage to get a faster nervous system faster input output, but it doesn't make you think faster. No, sure it does to a degree. A lot of your corticocortical interactions are via myelinated fiber. It's only the very short-range local axons that aren't myelinated in cortex. And I wonder about inner neurons? I'd have to look that up, yeah.
Speaker 1:I'm not sure I should have known that myself.
Speaker 2:But certainly if you want to send a signal from visual core V1 to V2, you're going to want a myelinated fiber to do that, because that's a goodly distance of millimeters, anything above a millimeter or even above a half a millimeter. You're going to want a myelinated fiber if it has to be communicated quickly and of course all of our sensory information needs to be communicated quickly because it's helpful, for sure, yeah, that guy's going to throw a spear at you, yeah need to be on it yeah, have you written up this broader approach on thinking about the role of EM fields and consciousness?
Speaker 2:yeah, I have, and that's where we need to go next. So I've been interacting with physicists who have the skill set mathematics to start to think about these things. How would a complex, dynamically changing electromagnetic field process something that that's a weak point? Yeah, that's all great that the emf is the mind and all that and that's where consciousness is, but how can that work? And why aren't all electromagnetic fields conscious?
Speaker 1:maybe they are someday.
Speaker 2:I think again it's a degree of complexity. The one thing I know for sure about consciousness is when you lose consciousness, like going to sleep at night, the complexity of your brain interactions dramatically decreases. I'm going to show that tomorrow afternoon.
Speaker 1:Are you speaking again? You're in one of the concurrence. Oh, I did not. Okay, excellent.
Speaker 2:Tomorrow afternoon there's a concurrent session on multiscalar electrophysiology or neurophysiology. So I presented in that Frontiers paper the measure of complexity that's based on phase lag in a EEG recording, on phase lag in a EEG recording. So when you're awake your chaotic attractors are like a sphere 360 degrees of exploration and freedom and infinite possibilities. As you go to sleep that collapses down to a rugby ball when you're in deep stage. One slow wave sleep With an anesthetic. You can squeeze that down even more like a football and at surgical planes of anesthesia it almost flattens down to a plate.
Speaker 2:A really squished sphere. It's an ellipse, a squished ellipse at that point. Sphere, it's an ellipse, squished ellipse at that point. And that turns out to be a very good measure of complexity of a signal. And I didn't have the figure back when I wrote the Frontiers paper.
Speaker 2:But on further playing around with data and looking at these things, if you, instead of plotting out a full attractor, two seconds or 10 seconds worth of EEG recording, if you just look at trajectories on the order of 100 milliseconds, 200 milliseconds, you see these really in an awake brain really complex, squiggly, convoluted, folding back on itself trajectories in, but they're all within the attractor and they will flesh out the attractor if you record it longer. But if you just focus on those few hundred milliseconds and then you anesthetize the brain and look at that signal, all of that complex folding and dodging and deacon goes away and you get a nice smooth trajectory through the same space it's just a lot less going on yeah, so that's the multi-scalar part of it, that you can see it in the full attractor if you record 10 seconds worth of EEG or longer.
Speaker 2:But if you look down at just milliseconds of recording, you also see the complexity, but it looks entirely different. It's all squiggles and wiggles and jiggles.
Speaker 1:How does it compare to PCI, the complexity?
Speaker 2:index. Actually it's quite different. It's quite different, but PCI has been known. The complexity index Actually we use. It's quite different, it's quite different, but PCI has been known since the 60s.
Speaker 2:Oh, really Did not know that yeah no, tononi won't tell you, but the early guys doing auditory evoked potentials. So in an awake subject, if you give them a beep, a tone, you and record the evoked response in auditory cortex. You see a complex, long-lasting waveform. When you anesthetize the same subject and give them the same auditory tone, you see just the early component and it attenuates it attenuates and there's none of this complexity that Tony's talking about.
Speaker 2:So that's just a fancy way of doing. An auditory evoked potential. Instead of giving a tone, you give a shock. But he's made a lot of play on something that's really not that novel. I always wanted what that means is that in the anesthetized brain, whether it's a tone or a flash of light or a shock to the scalp, any of those stimuli are going to cause reverberations and interactions in the awake brain. That goes away in the anesthetized brain.
Speaker 2:Why is that Anesthetics work at glutamate and GABA synapses and what they do is turn down the gain on excitatory synapses, turn up the gain on inhibitory synapses.
Speaker 1:So all of this complex stuff just goes away wiped out, yeah, so basically, connectivity is just being limited right across the board.
Speaker 2:Yeah, you're totally limiting the strength of connectivity. Connections are still there, but the volume control has been shut down.
Speaker 1:It's interesting your comments about PCI in relation to IAT because I was always wondering it's a great measure, but I'm not sure how.
Speaker 2:It's not a great measure. It's not part of IAT.
Speaker 1:It's not necessarily part of IAT in any way. It seems to be a pretty predictive tool. They had a 100% prediction rate for their common patients. Well, the auditory evoked potential is very predictive. Is it similar? Yeah, is it good?
Speaker 2:Yeah, the problem with both is they don't respond to all anesthetics in the same way at loss of consciousness. Nor do they behave well when you go through different stages of sleep. So that's where all of these evoke type measures of brain activity fall down, is they're not universal. They don't all say oh look what happens at loss of consciousness across any condition you want to look at. It doesn't work. Ketamine doesn't block the auditory of late ringing potentials any more than TMS shocks do, so it's basically a measure of the strength of connectivity and that's it.
Speaker 1:Yeah, and that's not, in your view, a reliable measure of conscious experience, et cetera. For some things it is, oh, for sure, for sure.
Speaker 2:Propofol induced unconsciousness. It works great. Um isoflurane works great. Nitrous oxide doesn't work at all. Ketamine doesn't work very good. Okay, and the clinical concentrate combinations like remifentanil and nitrous oxide.
Speaker 1:These things don't work at all, not so much so. To be clear, you're saying the PCI measure as a measure of consciousness does not work under these other anesthetics.
Speaker 2:That produce unconsciousness.
Speaker 1:Okay, that's a good detail to know.
Speaker 2:Just like the auditory evoked potential, doesn't either, or an electric shock evoked potential any of them.
Speaker 1:Anything you do to the brain you're just. What they're measuring is the strength of connectivity through the circuit so then, in your view, what would be a better measure of what they're trying to get us? So not just coma patients and whether they can recover or not, but of what is actually consciousness going on in the brain-body complex. What would be a better measure of that kind of complexity index?
Speaker 2:I think the measures of the EMF are better. So EEG for determining loss of consciousness. But again, EEG and magnetoencephalography also suffer this inability to universally detect unconsciousness regardless of the causal agent. So different anesthetics produce different patterns.
Speaker 1:Yeah, so there's no universal well conscious amateur.
Speaker 2:At this point, the one thing we that image I showed in the frontiers paper is much better. So it gets ketamine, it gets nitrous oxide we've got a paper okay, that shows remifentanyl nitrous oxide produces beautiful squishing of these attractors.
Speaker 1:So kind of the flat of the pancake. The less is going on in your model.
Speaker 2:Yeah, the flatter your pancake, which incidentally supports some early work by another Santa Barbara person, Nancy Reagan.
Speaker 1:They have a ranch, yeah, yeah, so she had these tv ads back in the 70s 60s. Whatever your brain on drugs yeah.
Speaker 2:So she had a beautiful spherical egg and then crack into a fry pan, flattens right out yeah yeah, that's your brain there you go so she was right on it yeah, we just did not. The neuroscientist nancy reagan, yeah we didn't uh fully appreciate her thinking back then never too late.
Speaker 1:This is good stuff.
Speaker 2:I think we're at time that's a great place to end it.
Speaker 1:Yeah, yeah, that's really good discussion. Thanks so much for joining me and um look forward for the talks I'll be looking forward to reading more about this whole field.
Speaker 2:I hope you're going to have another series in a couple of years, maybe.
Speaker 1:I hope so. I hope so too, I might have something new and interesting.