From First Principles - Can AI Help Wake Coma Patients? The Science of Consciousness (EP 35)

Episode Date: March 31, 2026

Hosted by Lester Nare and Krishna Choudhary, this episode is a deep dive into one of the hardest questions in neuroscience: what breaks in the brain during a coma, and can we figure out how to turn co...nsciousness back on? We unpack a new paper from Daniel Toker et al. that uses an interpretable AI framework — not a generic black box chatbot model — to reverse engineer the biological mechanisms of prolonged unconsciousness, recover known features of coma, predict new ones, and propose a possible new target for deep brain stimulation.SummaryWhy diagnosis is so hard — disorders of consciousness are not just about whether a patient is awake, but whether awareness is still present even when motor output is gone.The mesocircuit hypothesis — the episode explains how the cortex, thalamus, and basal ganglia may work together like an electrical grid to support consciousness.Interpretable AI, not black-box hype — Daniel Toker’s team built a biophysically grounded model that rediscovered known coma features and predicted two new biological mechanisms.A possible stimulation target — the subthalamic nucleus emerged as a standout candidate for deep brain stimulation, suggesting a new path toward restoring wakefulness.Support the showDonate: FFPod.com/donateFollow: @FFPod on X / Instagram / TikTok / FacebookShow NotesDaniel Toker et al. — Adversarial AI reveals mechanisms and treatments for disorders of consciousnessNicholas Schiff et al. — deep brain stimulation in a minimally conscious patientAdrian Owen et al. — fMRI evidence of covert awareness in a patient diagnosed as vegetative

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Starting point is 00:01:05 And this question is one of the hardest problems in all of neuroscience. What is consciousness? He used AI to reverse engineer the biological mechanism of unconsciousness in coma patients. AI has rediscovered known features of unconsciousness. And then it's also predicted two entirely new biological mechanisms. Hello, Internet. this is your captain speaking. Lester Nare, joined as always by my co-host and our resident PhD Krishna Chowdery. We are back for another deep dive episode where we are going to talk about a paper today that's trying to tackle one of the hardest questions in neuroscience about comas and how AI is helping us better understand the state of deep, prolonged unconsciousness.
Starting point is 00:01:54 This was a paper published in Nature Neuroscience by Friend of the Pod Daniel Toker at all on March 26th. And as always, we are going to learn about the science from the ground up because this is from first principles. Every year, tens of thousands of people fall into comas. And it's either from traumatic brain injury or a stroke, cardiac arrest, drug overdoses. And whenever this happens, some patients recover. some patients don't. We don't really know why some recover and why some don't. The other thing is for families that are sitting in that intensive care unit, there's a question that haunts them every time, which is, is my loved one still there? And this question is one of the hardest
Starting point is 00:02:55 problems in all of neuroscience, right? What is consciousness? It's not just philosophically hard, which that's above my pay grade and we're not going to get into, but even like mechanistically and clinically, this is a very hard problem, right? What is consciousness even physically speaking? Obviously, it has something to do with the brain. The human brain has 86 billion neurons. It's muscle of fat and neural tissue. And it's quite incredible that that, like, sack of fat and tissue is where we get this profound phenomenon of consciousness, right? Our ability to perceive, to feel, to think and to have this subjective experience of ourselves and the world around us. And it's all just from like this sack of like blood and fat in our skull.
Starting point is 00:03:48 Right. And one can ask, so it's somewhere in the brain, but what are the specific circuits that generate consciousness? And if a part of that circuit breaks, how does it affect consciousness? And then can I actually figure out how to repair it? right now doctors can observe that a patient is conscious or unconscious right because they're not responsive and they can classify the depth of unconsciousness on behavioral scales but all we can do really is like wait for them to wake up there are some new therapies right now that we're going to get into that are maybe getting at trying to wake them up but at the end of the day we still
Starting point is 00:04:30 don't have a way to peer inside the machinery of awareness and start asking like what is the thing that is broken and how do we fix it okay or how do we replace it there's still this delta between sort of what we have as the scientific understanding currently and the actual mechanism that generates that it's kind of a little bit of a dark cave yeah very much a black box in that sense right and that's why i really like this new paper it's a new study that i think represents a genuine step change in that field okay so it's a team that was led by Daniel Toker at UCLA, who is, as you said, a friend of the pod. He went to college with us at Princeton undergrad. Then I think he went to Berkeley for a PhD
Starting point is 00:05:16 and then came to UCLA and now has like a gig with UCLA and USC as a postdoc. He's also the brain scientist on Instagram and TikTok. He's got a bunch of followers really into science communication. You guys should check out his page. It's really, really cool. So the cool, the cool, the cool thing about this paper, the cool thing that Daniel did was he used AI to reverse engineer the biological mechanism of unconsciousness in coma patients. And the way that he used AI is very different from, I think, when people think about using AI to do science. They think, like, oh, Black Box LLM model, I, like, trained it on a bunch of data, and then it's going to spit out, like, a classifier, consciousness or not consciousness. There's part of that here. But what really
Starting point is 00:06:04 I think is cool about it is there's the AI has rediscovered known features of unconsciousness. And then it's also predicted two entirely new biological mechanisms. Because the way that he has engineered this AI is it's not a black box. There's actual mechanistic understanding about a model of the human brain that he's hard-coded in. And that's what the AI is sort of acting on. That's what the evolution of the AI is acting. on. And we're going to get into that. But I think it's very, very cool. And the implications are in every direction. I just want to make a quick note here. We use the term AI in a very general sense when we
Starting point is 00:06:47 discuss on the pod. It is a very expansive area of research with a lot of different subcategories and sub boxes. So a lot of times we will just say AI for shorthand because we have a lot to get to. But we don't mean AI equals LLM when we do so. It is sort of talking about the entire field of research at a high level. And we then get into the weeds of what we're talking about specifically. But just as a small caveat note, that's important because it is a vast, vast space that it's beyond just chatbots. Exactly. And this is very much not a chat bot.
Starting point is 00:07:22 Right. It's very, very cool. We're going to get into it. And the implications, I think, radiate in all directions, right? Something like 5,500 Americans currently are in a persistent vegetative state. and there's a larger number that's in a minimally conscious state. And this research offers a genuine scientific pathway towards treatment. From the philosophy of mind perspective,
Starting point is 00:07:43 it provides a very mechanistic specific picture of what makes a brain conscious. And then for an AI perspective, it's also very cool to think about how one can use underlying principles of AI architectures to understand something as complicated as consciousness, right? So it's a deeply personal question that I think this is answering. Like consciousness is the one thing I think that we can all be sure exists because at least we experience it. It's the Descartes, I think, therefore I am.
Starting point is 00:08:15 Clearly consciousness is a thing. Maybe the world isn't. Right. And quantum fields aren't. But consciousness, like 100%. Like I am me, right? Sitting here talking in this microphone. And you are you and everybody agrees that like that is a thing.
Starting point is 00:08:29 So it's a deeply personal question. And it's still a phenomenon that we, I think, understand the least out of everything. So any light that is shed on this mystery, I think, is certainly welcome. All right. So with that in mind, let's get into some of the history behind this type of research. And we'll start all the way with the ancient Greeks. Always. Okay?
Starting point is 00:08:54 Because the ancient Greeks, they had some crazy ideas. Like Aristotle thought that the brain was just a cooling organ for the blood. and consciousness actually lived in the heart, we're going to let that slide because other people like Hippocrates, the guy from the Hippocratic Oath, right? He noted that patients who fell into deep unresponsive sleep after a head trauma rarely ever recovered.
Starting point is 00:09:21 Okay? And the word coma comes from deep sleep in Greek. So they had already sort of classified normal sleep versus this pathological deep sleep coma. They had already kind of figured that out. But again, it was just sort of an observation, right? Then in the Renaissance, there came the anatomical revolution with Vyssalius. He published this massive manuscript called DeHumani corporus Fabrica in 1543.
Starting point is 00:09:51 He was basically like really into dissecting human bodies and gave us incredible drawings of human anatomy. So from there, now we've got an understanding of brain structure, right? But it's kind of like the machine is getting cataloged, but we don't really know when any of the parts are doing. So already by the early 1600s, we both had like a philosophical framework or concepts developing about classifying what these different parts of the body are doing and how that, like how that translates behaviorally, as well as sort of a very detailed cataloging of the physical structures. at least as it related to the brain and other key parts of the human body, you know, four or five hundred years ago. Yes, yeah, exactly. It was a catalog.
Starting point is 00:10:35 We didn't know what each thing did, but there was a pretty good catalog already, right? And then in the 1800s, we had some pretty revolutionary ideas. Paul Broca in 1861, he discovered this idea of cortical localization. There's an area of the brain now called Broca's area, and now we know that that damage to that area causes language loss.
Starting point is 00:10:58 We also know that electrical stimulation and the motor cortex causes muscle movements. So now we're starting to get into the brain, it turns out, is a machine that has specialized parts and each of these parts is doing something, right?
Starting point is 00:11:12 The other invention in the 1800s was electrophysiology. In the 1870s, Richard Katon placed electrodes on exposed skulls of rabbits and found that there was electrical activity. And then we see Hans Berger in 1929. he develops the EEG, the electroencephalogram, which is you put leads on the skull, and you can actually read electrical activity.
Starting point is 00:11:33 And he found that the brain electrical activity dramatically changes with the state of consciousness. Okay? So different patterns mean waking, sleep, anesthesia. So already now it's like, okay, the brain is doing different things during unconsciousness. So perhaps the brain is really the seat of, you know, consciousness. Yes. That kind of makes sense. So yeah, yeah, yeah.
Starting point is 00:11:57 Finally, 1949, Giuseppe Morozi and Horace Magwan, they published this landmark paper, and this demonstrates something called the reticular activating system. It's a diffuse system that runs in the brainstem. The brain stem is where your brain meets the rest of the body with the spinal cord. So it's kind of like the connecting part of the brain. And they found that that part of the brain, the part that connects the brain to the spinal cord, that is essential for maintaining wakefulness. So now we've honed in on this is the sort of general area
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Starting point is 00:13:34 So to make a crude analogy, we figured out the brain is the factory. And we now know that different parts of the factory have different workers. Yeah. The engineers are downstairs. The sort of manufacturing line is upstairs. The finance department's over here. Yeah. And, and, but, but we didn't really know where the boss's office.
Starting point is 00:13:54 Yes. Yeah. Where is the boss's office? Yeah. It seems like that's where it's the brainstem. Right. It's that part, right? And over the following decades, we've mapped out that brainstem in more and more detail. So we figured out there's something called a locust coriolis. There's something called a basal four brain. There's something that's part of the brainstem. There's the hypothalamus. There's the raffa nuclei. And so all of these like sort of parts, you see where the spinal cord is going in. That junction is where. all of this is happening. Which it's almost like even just from a crude structural, like just looking at it, you would imagine if the things that are most sensitive have the most protection, just locationally.
Starting point is 00:14:35 Yes. Locationally, that makes sense from one perspective of evolution. And the other perspective of evolution, I think, is that like the brain sort of grew out from that part, right? So it's like the oldest part of the brain is the part that connects it to the rest of the body because, I mean, let's face it. Like the brain evolved to control moving. Right? And so the brain controlling the rest of the spinal cord is sort of probably how it started. And then like higher and higher cognition formed around that, right? Like, oh, okay, I need a sense of place. I need a sense of time. I need a sense of problem solving. All of that starts forming around this like nucleus. And then the prefrontal cortex being the most advanced. That's the one that's like right, right in the front. Which, you know, it's very cool to think about it that way. Just like in terms of stages of development.
Starting point is 00:15:24 over the millions of years of evolution. Okay. Okay. So now we know that it's like kind of the brain stem, but we still don't have really an idea of like, okay, this thing connects to this, this thing connects to this, so this is powering that, that, that, that, and so on and so forth.
Starting point is 00:15:39 2007, there's a pivotal moment in consciousness research because Nicholas Schiff and his colleagues published this paper in nature, and it showed that continuous deep brain stimulation, this is the idea of you, we take an electrode, and we pulse it with an electrode, that is going to excite the neurons near that electrode. It's just you're pumping electricity deep into the brain.
Starting point is 00:16:01 That's why it's deep brain stimulation. And deep brain stimulation of the central thalamus helped a minimally conscious patient regain the ability to communicate and feed himself. Okay? This was a very big deal, because this was an ability that he had lost about six years earlier
Starting point is 00:16:16 after a traumatic brain injury. It's a preliminary result, single patient, notoriously in human consciousness, studies and things like that, the N is like very low. Single digits is you're already getting a lot. Because human, I mean, you're like experimenting on human beings, right? There's tons of ethical concerns. There's not a lot of like, you know, people who are willing to do this. And so even though the data is low, the fact that it worked means that there's something going on. So that's
Starting point is 00:16:44 sort of rejuvenated this research. And in 2010, that same author, Nicholas Schiff, he came up with something called the MesoCircuit hypothesis. Okay? Effectively, what he's saying is the following. The consciousness relies on a network of interactions between the cortex and the central thalamus. And that interaction is regulated by a part of the brain called the basal ganglia. We're going to focus on effectively three regions of the brain. Okay? And I'm going to use an analogy of an electrical grid.
Starting point is 00:17:19 Okay? A city's electrical grid. Yes. So the cerebral cortex, this is. is the part that's on the outside, the most sort of recently developed in humans. When we think about the brain and all the wrinkles, that's the cerebral cortex that we're seeing on the outside. And that outer layer, it's responsible for higher thought, memory, sensory processing. And in this analogy of a city's electrical grid, this is your network
Starting point is 00:17:44 of homes, podcast studios, you know, businesses that consume the electricity, right? Now, the central thalamus is the deep brain relay station. That's the part that's sort of on the right over there in the pink. Just above the brainstem. Just above the brainstem. Okay. So that's getting input from the cortex. And it's also giving input to the cortex.
Starting point is 00:18:04 Okay, so it's a two-way street. It's kind of like the primary power substation. Yes. It's pumping excitatory input to the cortex, but it's also getting excitatory input back from the cortex. So it's relaying a bunch of electricity one way on the other. So one of the examples being if you have solar on your house, you're sending electricity.
Starting point is 00:18:23 back to the grid. It's not just you're receiving it as a practical example. That's very good. Yeah, yeah, yeah. No, that's exactly right. And this feedback loop kind of helps both run. Right. Okay? In some sense. And then finally, there's the basal ganglia. And that's the striatum and the globus pallidus. That is a kind of regulatory system. And it's kind of like a voltage controller that manages the flow of power in this entire network. So in the summer, when it gets hot, they have to decide where to send energy, when they're not send energy. in order to not overflow. Like there has to be, there's somebody decides,
Starting point is 00:18:56 okay, we're going to shut down this neighborhood. Yeah. Because we need to power the nuclear. Yeah, yeah. Yeah, exactly. As a crude analogy, it's kind of routing signals
Starting point is 00:19:05 and it's controlling both the power stations and the homes to make sure like nothing's, yeah, there's balance and nothing's going out of the way. Yep. Okay. So that's how sort of the consciousness mechanism is working in a healthy patients.
Starting point is 00:19:17 What happens during a coma? Well, according to the meso-circuit hypothesis, here's what happens. When there's widespread, brain injury, right, like from a traumatic brain injury or a stroke, so a bunch of neurons die because they don't get oxygen and things like that, your power lines are going to be down on the cortex, right? So you're going to get localized areas of power cuts, like we do in LA sometimes when somebody steals our copper from underground. Yes. But anyways, the cortex is now
Starting point is 00:19:45 going to reduce its excitatory input to the thalamus. That connection is broken, as you can see, on the left. The thalamus in the cortex, that's now a dotted line. instead of on the left, it's a solid line. Okay. The other thing is, there are these special neurons in the striatum called medium-spiny neurons, and what they do, they're super prone to metabolic stress death, meaning you remove a little bit of oxygen and they'll just die. Okay, they're not very resilient.
Starting point is 00:20:14 They're very finicky. And if those guys die, then the striatum is going to not inhibit the part that is inhibiting the thalamus. It's a double negative now. Okay. Okay. So because of that, so what it's doing is usually the striatum is like inhibiting the part that is putting breaks on the thalamus. Okay.
Starting point is 00:20:36 But now that that break is gone, the first break is gone, right? The second negative is going to go even more negative. Okay. And it's going to start inhibiting the thalamus even more. That's why that red line just got fatter. That makes sense. Right? So the thalamus is one, not getting any input from.
Starting point is 00:20:53 the cortex because the power lines are down. And second, the part that was putting brakes on the thalamus has now gone hyperactive and putting even more breaks on the thalamus. So the thalamus is getting inhibited. It's getting shut down more and more in a coma because of these very tiny defects that have happened in exactly the wrong areas. Yeah. So this is very interesting.
Starting point is 00:21:14 And what we're sort of saying here is the traumatic brain injuries are disrupting the normal flow between these three fundamental component parts. The cortex, which is like the end destination, the homes example, the thalamus, which is sort of sending and receiving, and then the striatum and plaitum that are kind of controlling the amount of what is or is not being sent and where it is or is not being sent. Exactly. And it's exactly at the right part where the thalamus, which is the relay station, is just getting signal to shut down. Yeah, yeah, yeah, yeah. And when that shuts down, Now this entire circuit of consciousness is getting shut down.
Starting point is 00:21:54 It's almost like the fail-safe system that happens at a substation if there's some overload, just gets stuck in the locked position. Exactly. Exactly. And there's some evidence that this meso-circuit hypothesis is probably correct. There's certain stimulant drugs, for example, amantadine, which enhances the inhibition to that break, like the part that's inhibiting the thalamus. Amantadine inhibits that part.
Starting point is 00:22:20 So it's no longer going to inhibit the thalamus kind of works. And it kind of wakes up patients. It's turning it to overclock. Yes. Yes, exactly. So there's some mechanism where these drugs are kind of working with the mesocircuit hypothesis. But at the end of the day, still a hypothesis because it's not very granular, right? It's just like, oh, giant brain area.
Starting point is 00:22:41 You know, like there's, but the giant brain area has millions of neurons. Right. That are all different types. What type? What type is doing what, right? And also, you can't really test it directly because the bottleneck is standard animal models are really bad at mimicking human comas, this prolonged unconsciousness. And that just has to do with the fact that animal models like rodents, the brain is structurally a very different thing. Right. Right. Even though it's still a mammal, one of the things that we think happens during traumatic brain injury that causes this kind of coma is the idea of a diffuse axonal.
Starting point is 00:23:18 Injury. Here's the idea. You've got the cerebral cortex on the outside. There's gray matter, which is like sort of the cell bodies. And then there's white matter. You might have heard of that gray matter and white matter. Gray matter is kind of like the cell bodies. The white matter is the axons. These are these like cables. Like, you know, the high voltage cables that come from Hoover Dam to L.A. The axons are kind of like that. They're the high voltage cables. Now, if we go to a photo 13, what you'll see is the white matter is kind of in the middle. And it's like connecting. these areas of gray matter. But if you have a traumatic brain injury, let's say you got into a car crash or like, boom, like your brain had severe G-forces on it. Those axons, which are the cables, those are going to rupture first. Yeah.
Starting point is 00:24:03 Right? Yeah, yeah. Now, with a small rodent, the brain is not big enough to feel that kind of G-For stress, right? Ours is big enough where like, and we're like doing crazy things as humans. we're like we're driving around at 70 miles an hour. We're like we're now subject to dream G forces if something goes wrong.
Starting point is 00:24:23 Right. And so our brain is just not evolved when we were hunter gatherers in Africa like evolving. Right. The evolution didn't think, hey, I should probably make this brain, you know, withstand getting hit by another 350 pound man in an NFL game. Yeah, exactly. Okay. So there's a mismatch between like what the brain is designed. like the environment that the brain is designed in,
Starting point is 00:24:50 and then what the brain was capable of creating, right? Which is like human beings in cars and all this other crazy stuff, skiing and then hitting a tree and things like that, right? Right. So, and we simply can't test in rodent models. Right. Okay.
Starting point is 00:25:07 And this is something we talked about on a recent previous episode too, about just, you know, there are a lot of opportunities to use animal models, which the purpose of, which, yes, for folks who are, you know, PETA adjacent, et cetera, the ethical concerns about testing directly on humans are so prevalent that it's perceived as a lower ethically bad option. 100%.
Starting point is 00:25:32 And for an outcome that's going to save millions of lives at some point in the future. Yeah, but here, like, it doesn't. It doesn't. The ethics, like, is even more problematic because, well, you're not going to get anything out of it. Right. Right. And so you're just, yeah, you're just like.
Starting point is 00:25:46 wasting animals at that point, right? Right. And that's not something that we want to do in science research. Right. So that's one bottleneck. Okay. Which is just animal models are not a thing. The second bottleneck is the diagnostic crisis.
Starting point is 00:26:00 Okay. This is in general with consciousness in medicine. Okay. Consciousness has two fundamental components. There's wakefulness, which is like arousal, like when you're awake. And then there's also awareness. That's the qualitative experience of like me being me and seeing you and everyone else, right? This is some qualitative subject experience that only I have about what it's like to be me.
Starting point is 00:26:21 Right. So disorders of consciousness that comes from physical trauma and oxygen deprivation, there's several different types. So in a coma, you have neither arousal nor awareness, right? Because you can't be awoken. Yes. There's no sleep wake cycle. Yes. And they fail to respond to stimuli.
Starting point is 00:26:39 The lights are off. Yeah. Lights are off and maybe nobody's home. Right. Okay. Vegetative state means it's also called. unresponsive wakefulness syndrome. You have wakefulness.
Starting point is 00:26:51 And you have a sleep wake cycle, but perhaps you have no awareness. So the lights are on, but maybe nobody's home. Okay. But now it gets kind of weird. Like, what if they are aware? Yeah. But they just can't have any agency over their motor controls. Right?
Starting point is 00:27:10 So how can you tell? So someone's home, but they can't answer the door when you're wearing the doorbell. Exactly. Yeah. Lights are on. lights are on. And someone is home. Yeah.
Starting point is 00:27:17 You ring the doorbell, but they can't answer. Yeah. That's very good. Yeah, exactly. How can you tell? Right? This is a... Yeah, that's subtle.
Starting point is 00:27:24 That's very subtle. And for the longest time, wasn't really considered until science paper 2006 by Adrian Owen. It's a landmark paper. It's quite incredible. This was a wake-up call, so to speak. Okay. He used functional MRI to ask a patient that was diagnosed in a vegetative state to imagine
Starting point is 00:27:44 playing tennis. and imagine walking around her home. I love scientists so much. Okay? And the brain activity from that fMRI study was identical to someone who was fully aware. So she's there in this vegetative state. There's no way that she can express her awareness. But if we look into the brain MRI, it's the same of someone who's aware.
Starting point is 00:28:09 The idea being they may not be able to move their hands to touch a button or verbalized as the means by which or move their eyes. Or move their eyes, which is techniques that have been used before to communicate. Now we're just saying it's because the awareness is in the brain and so you shouldn't actually need any of these secondary
Starting point is 00:28:28 avenues to communicate and the only way to make the differentiation between is someone home versus is someone not home reference point. You have to go directly to the source if all of their physical capacities are not available to them, which does not necessarily mean that no one is home.
Starting point is 00:28:50 Exactly. It's like no one's answering the door, but here it's kind of like we did an x-ray of the home. And the person is moving around. Right, right. We have the thermal. Yeah, exactly. You know? Okay. It's, I thought that was a very cool paper. That is very clever. It's very clever. And now, now it's a real crisis, right? Because now there's a third. It's called minimally conscious state. Okay. And it turns out that 15 to 20 percent of patients that are classified, as vegetative actually might have covert conscious awareness. That's a lot. That's got to be terrifying.
Starting point is 00:29:21 And that's got to be so terrifying. You know what I mean? Because you can hear and see everything happening around you and you cannot engage in that environment. That's just unbelievable. And this was only 20 years ago, 2006, right? After this 500 year cycle we've just talked about. Yeah.
Starting point is 00:29:34 So, I mean, this field is just one of those where you can really sit back and be like, wow, we really don't know much about the brain. Right. Right. Right, right. Because this is like kind of, you know, people's, this goes to the materialist, uh, non-materialist debate. You know, is it that consciousness arises out of matter, uh, or as consciousness primary, which gets a little, that's, again, that was above our pay grade and not the focus of this podcast. Yeah. But it is, it is one of those. It's the first question. Yes. Because once you get, yeah,
Starting point is 00:30:08 you know what I mean? Like, you have, you can't, everything else downstream is really impacted. By which of those two, right? What are we talking about? Right. Who am I? Who are you? And what the hell is going on? That's how I like to say it.
Starting point is 00:30:24 You know? And so with these kinds of studies, it's really like underscoring how much we don't know. Right. About this, right? And now 15 to 20% of patients we're saying are classified incorrectly. Which is fascinating. Because I mean, I'm sure after that study, a variety of, because the FMR, Our eyes are not hugely a negative for a patient.
Starting point is 00:30:47 No. So at least as a way, especially for families or anybody to try, but in any event. Exactly. So now we finally get to Daniel's paper. Daniel Toker in nature and neuroscience, adversarial AI reveals mechanisms and treatments for disorders of consciousness. It's a really innovative way of using machine learning and the vast amount of data that's now available on comatose patients, vegetative patients.
Starting point is 00:31:15 He's made an in-silco model of coma, so a computer model of the brain, that circumvents the lack of mouse models. So now I have a model in the brain that I can play with. A model of the brain in my computer that I'm fairly confident is quite good that I can play around with. Because the ideas, it's based off of this real-world data
Starting point is 00:31:37 of actual anonymized. Yeah. Data. Exactly. And then I can figure out a kind of mechanistic model about how consciousness works, what gets disrupted to make a coma, and then it becomes a kind of discovery engine. From that, we can mess around with it and propose new treatments. And he is doing all of these.
Starting point is 00:31:56 Very well done, Daniel, by the way. Quite good. Nicely done. Quite good. Again, the brain scientist on Instagram. And before we deep dive into it, let's do a little bit of housekeeping. Yes. So as always, we are so grateful for all of you to join us for these research deep dives.
Starting point is 00:32:15 It's just an incredible, not only an incredible time to be alive, but the opportunity to really understand not only what we're learning today, but how it works and what the history of how we got here, you're not going to get it anywhere else. And this is why we love doing this show at Farm First Principles. And it is hugely helpful to us to continue to bring you the best and greatest breaking science research. As we, as I always say, fight the billionaire algorithms, a like, a share, a comment, a DM, sending it to a friend, bringing it into Journal Club is hugely, hugely helpful for us, where it's, again, still just the two of us running the show to be able to give
Starting point is 00:32:54 this to you multiple times every week. If you would like to become a patron, you can donate to the pod at ffppod.com backslash donate any and all support monetarily or non-monetarily is hugely, hugely valuable, and we really greatly appreciate it. I have no other show notes this week, and I'm very excited to dive back into this paper. Let's do it. Okay. So, first thing I want to do, right, I want to use artificial intelligence to make a discovery engine from my brain, figure out why comas happen, and then propose treatment.
Starting point is 00:33:28 That's the end goal of this paper, okay? First thing I want to do is train an AI detective that is capable of diagnosing consciousness from raw brainwaves. Okay. Just can I identify consciousness if you give me the, you know, sort of brain activity, the electrical activity of a brain? So he made something called a deep convolutional neural network. These are just our normal, you know, CNNs that we hear about,
Starting point is 00:33:54 giant network of artificial neurons that is trained through back propagation, you know, supervised learning, which is just we've got about 680,000 10-second electrophysiological recordings. So 680,000 recordings of brains, electrical activity. These recordings come from humans, monkeys, rats, and bats under anesthesia, in a coma, and wakeful. So a swath all across mammals. So that means it's not going to really hone in on some human feature. Right. It's going to, it's going to really start thinking about what is the nature of consciousness itself. Right? And he made three discriminators. So he made a cortical neural network. that was going to get trained on the cortical data.
Starting point is 00:34:40 There's a thalamic, and then there's a paladial. That's the three sort of big brain regions that we were talking about in that meso-circuit model, right? The cortex is your grid with all the homes and the podcast studios. The thalamus is the relay station, and the paladial station is kind of like governing what's going on between these two. Right? Yes. Okay. Once he trains it, he validates it.
Starting point is 00:35:09 It's pretty good. The AI score for consciousness, which is plotted on the Y axis, is correlated with the ground truth score of consciousness, that it was given to each sample in the test sample. Okay? Which means that like the AI, this deep convolutional neural network, is given a sample that it's never seen before. And it's told to guess how conscious it is based on a number between zero and one. That number is correlated with the ground truth. Okay, so that means it's working. Yes.
Starting point is 00:35:39 Okay? Yes. The other big one that I quite liked is from figure 1J, if you see over there. What that shows is that the AI was able to classify fully paralyzed ALS patients as conscious. Remember in ALS, we did the story where it's a motor neuron disease, right? All of your motor neurons go away. So you can still be conscious, but you won't be able to fully express that. here they looked at eFIS recordings from ALS patients
Starting point is 00:36:08 and there's no significant difference between them and healthy cortical activity. This is actually a fascinating follow-up to our ALS story because we did a great deep dive on understanding what it actually is mechanistically. Yes. And it dovetails with what we said earlier, which is just because your motor functions go away.
Starting point is 00:36:28 ALS is a perfect example of what we were just talking about. It doesn't necessarily mean that there's no one. home. Yeah, yeah. That's very... Exactly. And this was able to find that, right? Without motor output, you can now classify. That's... So already big win, figure one. Yes. Yes. That is huge. Right. That's good. That is huge. Okay. Now, we've made a detector. We've made a detector of consciousness. Yes. Now that we have a consciousness detector. Yes. Let's make a brain simulator. Okay. That can make my own brain signals. Okay. Okay. And this is where we get into the real why there's AI in the title. Okay. Okay.
Starting point is 00:37:04 because just making a deep columnusional neural network that will classify, that's just an autonomous classifier. That's like 10 years old. What are you doing? You're not going to get in nature and neuroscience like that. And Daniel knows that. And this is for the social clips. If we end up clipping the first half without the second half,
Starting point is 00:37:22 please watch the pod so you get the full story. Yeah. So they're not like that. I can't read that's a nature neuroscience. Yes, we know we can't fit an hour long thing on to Instagram. Yeah. Okay. So now what he's going to do is make a brain simulator.
Starting point is 00:37:37 He's going to combine that discriminator that he got, the AI, the consciousness detector, with something called a generative adversarial network. These are GANS. Traditionally with GANS, I mean, they're kind of used to make generative AI, like, photographs and things like that. Here's how it works. So this is very different from like a diffusion model, which is usually kind of used in the Zykeist.
Starting point is 00:37:58 Gans kind of didn't have popularity. They had popularity for a while. Yes. And then diffusion kind of went up. and became the generative sort of paradigm. But then now GANS are kind of back up. We don't really know which architecture is going to win in the end. But here's the idea, okay?
Starting point is 00:38:13 So you've got something called a forger, which is trying to forge real-life data. For example, in this case, what we're trying to do is create real faces. So we're going to have a data set of real faces. And then we're going to have a forger. That's the generator over there. And that's going to generate faces. Yes.
Starting point is 00:38:32 Okay? And then we're going to have a discriminator on the other side that is going to take the real data and going to take the forged data and try to figure out which one is forged and which one is real. Now, in the beginning, it's going to be obvious. In the Beninging. Yeah. In the beginning because the forger doesn't have any training. He's just going to be making up random nonsense. Right.
Starting point is 00:38:51 So the discriminator is going to be able to look and be like, oh, yeah, this is real, this is fake. But as the forger gets better and better, because that output of, hey, this is fake, you keep making fake stuff. I want the real stuff, that output is getting back propagated through to the forger. And the forger is thinking, okay, how do I get better? How do I get better? Yes. Pretty soon, after multiple rounds of training, the forger is going to get good at making the real data, such that it fools your discriminator.
Starting point is 00:39:19 Yes. Okay? That's the generative part and the adversarial part is you've got two networks that are adversaries. There's a detective that's trying to detect the fakes. And then there's a forger that's trying to create even better fakes. That's the adversarial part, right? Wishing you could be there live for the big game,
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Starting point is 00:40:20 Listeners of this shell will get a $75-sponsored job credit at Indeed.com slash podcast. That's Indeed.com slash podcast. Terms and conditions apply. Need a hiring hero? This is a job for Indeed sponsored jobs. For anyone who's ever used image generation, particularly mid-jurney, this structure is exactly the reason why you'll see a blurry, weird thing when you first initiate the image generation.
Starting point is 00:40:46 And then it's going through the cycle. You just talk about it. The fidelity gets closer and closer and closer and closer. Until it gives you the final, like, produced, like, image. This is like the whole stable diffusion kind of came in and changed. Yeah. And that one's slightly different. Slightly different because, so what you're talking about is very, very close to generative adversarial networks.
Starting point is 00:41:06 Because at the end of the day, how the forger creates the fake stuff is it starts with some kind of random noise, which is what you see there. And then it starts manipulating that noise to create the real thing, right? So what you're seeing there is the act of the forger, in some sense, going from noise to the real thing. But the training part is something that's already been done by mid-jurney on the back end. 100%. 100%. And so that's the generative part. Okay, great. So now, great, that's how you make a fake Picasso and a real Picasso and things like that.
Starting point is 00:41:40 How are we going to use that to figure out coma? Yes. All right? This is where Dan comes in hot with an interpretable biophysically grounded meanfield model. Okay. And that is what is cool. So on the upper left, that's a, figure A. Yes.
Starting point is 00:41:57 Okay. On the left-hand side, we've got our DCN, the convolutional neural network, that's our detector, that we had trained previously in figure one, right? There's other detectors in here that'll actually figure out, is this real or fake data? That one is saying, is this unconscious or conscious data? There's other ones that are not in this back end. You have to go to the supplement to see it, where it's like, is this real data or fake data? Because first we want to just create real-looking data. Then we'll worry about, okay, am I creating conscious data or unconscious data, right? So there's multiple steps to this process. But the key is that the forger is not a black box.
Starting point is 00:42:33 Okay? The forger is actually a three component, within which there's multiple components. But you know that mesocircuit hypothesis of like there's a cortex, there's the basal ganglia, there's the thalamus, and these guys are talking to one another. Each of those boxes is its own little neural network, right? And it's a biophysically realistic neural network in the sense that it's not. just a bunch of artificial neurons that start at noise. What it's doing is it's saying, okay, how does a biophysical neural network work? Well, some input comes in. Then there's going to be like channels, like, you know, some neurotransmitter is going to have some characteristic time scale. Other
Starting point is 00:43:15 neurotransmitters are going to have other characteristic time skills. There's going to be excitatory neurons which do positive feedback. There's going to be negative inhibitory neurons that do negative feedback. These I can hook up mathematically using differential equations and I can create a biophysically realistic model. It is no longer a black box. And instead of using back propagation to change the weights between each neuron, what I'm going to do is use something called a genetic algorithm to change the parameters of my biophysically realistic model, meaning how many excitatory neurons are there, How many inhibitory neurons are there? How is the connectivity?
Starting point is 00:43:56 What is the time scale of the interaction? Things like that. Things that are actually relevant when we think about what is a brain doing. And is in some sense the reason why it's like that algorithm is necessarily bounded by what the realistic value ranges are. Exactly. And that's why it's not a black box because you know that, oh, it's either going to be excitatory neurons or either going to go between X and Y.
Starting point is 00:44:23 And that's a realistic normalized range. Exactly. That's one of them. And the other one is we can literally point to components of the model and be like, oh, it's the excitation and the thalamus. Ah, yeah, yeah. Like that's, yeah, yeah, yeah, yeah. I can literally be like, oh, it's this part.
Starting point is 00:44:36 Yeah. With a GAN, it's like, with normal neural networks, I don't have no idea. Yeah. Like, you know, I type in, make me a cat on a horse. I have no idea in the trillions of parameters where it decided cat, where it decided horse, how it figured out to put the cat on top of the horse. Here, literally, I could just be, I could look into the parameters. I can see how they evolve with training and figure out what is actually going on.
Starting point is 00:45:02 That's very good. And then make that extrapolation from there to the brain. It's very good. That's very good, I think. That's very good. Right? Yeah. And that's one of the things I like a lot.
Starting point is 00:45:11 Yeah. Right? This loss function, he had a loss function that sort of like figures out, right? How to how to change the parameters. and this loss function incorporates the outputs from the networks that's trained to classify real versus synthetic data. It also has outputs from the consciousness detector that we had done earlier. It's also got a way to identify seizures. And as you said, it's got these empirical constraints on the firing rates of these neurons.
Starting point is 00:45:37 As you said, like, right? Excitation can't be that high. Inhibitory neurons are usually higher firing rate than excitation. Things like that, right? And the interregional communication patterns. Right. Like, excitation is long range. Inhibition is usually short range.
Starting point is 00:45:51 This is stuff you can bake into the model. This is quite nice. Right? This is quite nice. I love the fact that it's not black box because that's one of the things that I hate about, like, just large neural networks. Yeah. It's just, I have no idea where anything is happening. Yeah.
Starting point is 00:46:04 And it's also so different from the culture of software. Yes. Since the, it's beginning, which has been that everything is like explicit. And you can literally point to where exactly, like the trace callback of where something is coming from. This is the going back. to that type. Yeah, which is great. Which is great.
Starting point is 00:46:19 This is like, yeah. Fantastic. And so once this genetic algorithm has trained my, you know, brain maker. It's an artificial brain. Now we can ask, okay, how about we reprogram the objective now? Okay. It was just making real world data. Now I reprogram the objective to make comatose data.
Starting point is 00:46:41 So I can use that first neural network to be like, give me coma data. Yes. Right? And then now that genetic algorithm is going to tweak the parameters such that I get coma type data. Yes. And I just want to re-bring this back in because we have done the training and done the validation based off of a ground truth, real source of actual information. Yeah. We have all of those 10 second long clips. Right. That's that's, like, it's not making this from whole cloth. No. Like I just, that's like a really important concept. Yeah, and there's multiple stages of training. It's like he's he's figured out a way to, you know, you can't just tell a biophysical model, make me coma. Right, right.
Starting point is 00:47:22 You got to first be like, no, no, no, let's make just a normal data. Give me data that can fool even me to thinking, I don't know if that's from a real patient or from my brain simulation, right? I'm sure he did like checks just on his own. Yes. Where like after the whole thing, I mean, you look at it's like, okay, that looks pretty good. Yes. Right. And then you go, okay, now give me a coma.
Starting point is 00:47:42 And he was successfully able to recreate known phenotypes. Like on the right hand side, we've got high voltage delta oscillations. This is something that happens in coma, like the slow sort of oscillations that are super high voltage. We've got burst suppression that's on the bottom side. You've got this big burst and then just seconds of inactivity. Again, something that's there in coma patients. What's cool is there's no explicit programming of prior neuroanatomical knowledge on what is the difference. between a coma versus a normal brain.
Starting point is 00:48:15 Okay? Just the genetic algorithm and that detector that I had of coma versus conscious. Yes. Just that and the genetic algorithm has now independently discovered some of the core tenets of that mesocircuit hypothesis, right? What did the mesocircuit hypothesis said? It said that if I weaken cortical drive coming in from the cortex, that's going to cause a bunch of random crap. Yep. That's what my model is doing.
Starting point is 00:48:44 So as a first pass, it's already kind of on the right track. You can smell it in the water. I'm on the right track because the normal stuff that I kind of know about the meso circuit that I hadn't baked in explicitly, it's already figuring that out. It is able to intuit what we've already done over this last five, six hundred years that we talked about. out of the box without, this is sort of what people say about benchmarks and AI models. It's like, well, if you train it on the benchmarks, that it's going to do good on the benchmarks. Yeah.
Starting point is 00:49:18 And so the point here, it's not, the answers to the test were not provided as a part of training. And so it's getting answers that are not tainted by sort of giving them the cheat sheet before. Yeah, yeah, yeah. It's just looking at how do I make a coma. And already it's recreating parts of the MesoCircuit hypothesis that we know are probably true. Right. Okay. So that's already impressive. The next part is the impressive part, which is what is the new stuff? I just want to say this is all already very
Starting point is 00:49:49 impressive. And just as another caveat, we're talking about Daniel specifically. This was obviously a team and this is incredible work by everybody on the team. Yeah, yeah, yeah. But Daniel's our friend. So that's why we're talking about Daniel. Yeah. All right. So but clearly yeah, this is this is very I mean, it takes a lot of data. It takes a lot of like it takes a lot of brain. It's always a team effort. Yeah. Every time we're talking about it's always the team of her. So let's get back to Daniel. Okay.
Starting point is 00:50:17 Here's what he's going to do next. Okay. So the one part of the mesocircuit hypothesis, which is like cortical drive goes down. So the power station, like the normal power grid is down or the, there's elevated firing in the palatal population. So that's going to stop the, that's going to inhibit the thalamus even more and things like that. That stuff is already corroborated.
Starting point is 00:50:39 Stuff we already knew, this thing is kind of confirming. Okay. Now, does it do anything new? Well, yes. There's something called the selective disruption of the indirect pathway. This is a new prediction from the model. Here's what's happening. So it turns out the prediction is that the coma is actually driven by the degradation of certain medium-spiny neurons.
Starting point is 00:51:05 Remember those neurons that I was telling you about that, like, they just die if there's, like, any sort of. stress whatsoever. Or like a little bit of loxygen deposition. Yeah. Immediately. There's like, okay, no, I'm done. There's selective degradation of a certain type of medium spinding neuron in the striatum that is projecting to the part that's putting on brakes to the thalamus.
Starting point is 00:51:27 Okay. And this very specific pathway is new. Okay? The classical meso-circuit hypothesis is just like, oh, there's like stridal dysfunction. It's like the whole brain region. Yeah, yeah. Right. This thing is saying that the indirect pathway, which is specifically this D2 receptor expressing medium spine and neuron, this very specific subpopulation in the striatum, that's the part that is getting weakened.
Starting point is 00:51:57 And when that gets weakened, that's going to ultimately suppress the thalamus at the end of the day. Like that thing that I was telling you about, but now it's identified a little part. It's not just all of L.A. County. We got it down to a street block. Yeah, and a specific type of house type thing. Right. Right. Okay, so how do you find, that's your prediction.
Starting point is 00:52:16 Predictions are only as good as the data that corroborate. Right. So how do we corroborate it? We use something called diffusion tensor imaging. So this is an advanced form of like MRI. Oh, this is beautiful. What we can look at is trace. This is very cool.
Starting point is 00:52:30 What you can do with MRI is magnetic resonance imaging, right, where you look at like hydrogen atoms in, whatever biological tissue and you can actually see that using this magnetic resonance imaging technique. I'm not going to get into how MRI works, but effectively we can trace hydrogen atoms.
Starting point is 00:52:50 Water has a bunch of hydrogen atoms. So we can measure the directional diffusion rate of water molecules along the axons, along those fibers of those neurons, right? And we can measure in white matter, the water is
Starting point is 00:53:06 going to move faster along the length of the axon than across. And so we have a directional idea of like how diffusion of water is going. And diffusion of water is a proxy for kind of how neurons talk to one or another. Where is it? How's the traffic and flowing? Right? Yeah, exactly. So what they did
Starting point is 00:53:22 was use this DTI, diffusion tensor imaging of 51 patients with disorders of consciousness. And you can show that there's significantly lower striatum to GPE streamlines. That's the break on the thalom
Starting point is 00:53:38 that prediction is lower in vegetative state versus minimal consciousness patients. No way! Yeah. So just to take a step back, right? From this model, it made a prediction about where specifically in this region of the brain that is controlling the flow between the thalamus and the cortex is the point where the degradation, like the degradation of this specific area is what's actually driving the problem. And this connection is where we would find it.
Starting point is 00:54:10 And so it said, this is the road and the house where the problems, like, arise out of. And then we said, okay, well, we have all this actual MRI data from real patients. So can we look at this road, this house, and real patients that the model predicted you would see degradation in, in an outsized ways compared to surrounding area? Yeah. I mean, no, they compared vegetative versus minimal incognitive. Right, right. Because we've got those two sets.
Starting point is 00:54:41 Yes. And if there's a difference, there should be some statistically. Some delta between those two. The vegetative will have more of the degradation than the minimally, oh, my God. Yeah. And so on the left-hand side, we see that significance. There is a significant difference. On the right-hand side, he did sneak the sin.
Starting point is 00:55:00 The P-value is only 0.07. So it's not significant. but it's there. And perhaps if you were to pull the two data, it would become even more significant. But it's the, there's at least something, right? And the N is low.
Starting point is 00:55:14 Yeah. Right. So obviously like significance is not, we're not going to get like Higgs boson 10 to the minus five significance here, right? Where literally to do that, they had billions of particles colliding with each other. Right?
Starting point is 00:55:28 So you'll never get the significance level of traditional like physics. but the effect, it seems, is there. And with more and more data, perhaps, it's going to be an even bigger effect. Makes sense. It was really kind of a proof of, like, minimally viable proof. Yeah, yeah. That this hypothesis of this little prediction that I have,
Starting point is 00:55:50 it's probably true. It was good enough for nature and neuroscience. Yes. Not bad. Exactly. The second thing that they did was predict, this whole AI architecture predicted that there's increased synaptic
Starting point is 00:56:02 coupling between inhibitory interneurons, meaning those negative feedback neurons that I was telling you about, these are sometimes called fast-spiking PV-plus neurons in the cerebral cortex. Those negative feedback neurons in our cerebral cortex have a lot of coupling in between them. So it's like the negative feedback is coupled to the negative feedback, which is coupled to the negative feedback, right? That is what the AI model is predicting. So to test this, you go to transcriptomics. Transcriptomics means I'm going to now read the MRNA that is in my cerebral cortex.
Starting point is 00:56:38 Okay? And I'm going to see what genes are being expressed in patients that have vegetative state and patients that don't. Yes. Okay? Healthy versus those in coma. Yes. What they find is there's an upregulation of two genes, the VGF and the SCG2. These are genes that when expressed in these interneurons,
Starting point is 00:57:00 they drive synaptogenesis, meaning they drive this feedback mechanism, this coupling. Yeah, yeah. That, right? This is really, this one's pretty significant. Yeah. This one's way more than in both those genes. Yeah, yeah, yeah, yeah. Right.
Starting point is 00:57:17 And this is, again, data that's out there. Right. Right. Right. Right. Exactly. And I think the, this is kind of, again, in terms of like a frame of reference for, I've seen the conversation around quote unquote, be very different within some corners of the science community versus the general public, because a lot of researchers view it in this way,
Starting point is 00:57:39 where it's like, okay, this can be a sort of intermediary layer where I can rapidly prototype and generate predictions and rapidly be able to test that against real data in a way where I don't have to abuse my postdocs. Yeah, yeah, yeah, yeah, just abuse the undergras. here's a thousand images labeled them. Right. Right. Sorry,
Starting point is 00:58:08 undergrads are always going to. That's tough. It's tough life. We've all been there. We all want those letters of recommendation. You got to work the sweat. This is really interesting, though, because now the predictions are also on two very different planes. Yes, that's a very good point.
Starting point is 00:58:26 You know what I mean? Like, in terms of what's... Yeah, because when we think about those three, those three components, of our city, right? The cerebral cortex is the homes and the businesses. That PV plus interneuron thing has to do with that part. Right. Right. And then and then the, the brain imaging part. Yes. That one had to do with the thalamus and the relay stations. Correct. Right. Right. So all three parts of the mesocircuit hypothesis are working together. And this thing is giving predictions, as you said, on all of them. Right. Right. Right. In a very interesting
Starting point is 00:59:00 ways. And again, this continues to go back to the fact that we have all these existing tools like transcript transcriptomics enables the ability to know what genes are being expressed. Yeah. And one thing I just want to say is like to the team that made this
Starting point is 00:59:18 paper happen, right? I admire the resourcefulness. Right? Because it's one thing to have an AI model and make predictions. Right. And it's another thing to think, okay, here are the predictions. how can I make the argument that this is real? Right.
Starting point is 00:59:34 How can I check? It's always about checking. Yes. And they were so resourceful that they found these kinds of data sets. You know, maybe they talked. I don't know exactly the details. I don't know if these are open or not, but you go talk to somebody who has that data set. Right.
Starting point is 00:59:47 You meet someone at a conference. And they're like, hey, actually, you can look into mine, you know, put me as an author. You know, so like. It's very clever. Yeah, I think that part is nice. the whole from the from the ideation of like let's give it a try to then how are we going to be able to prove to review or two that this is not all nonsense yeah yeah exactly i got i got um lunch with daniel about three weeks ago and he was telling me about this paper and he told me
Starting point is 01:00:17 like and lino the thing predicted this and the first thing i asked well yeah but like you know how do you know the model isn't just bullshit and then he told me about these two techniques I was like, okay, that's actually pretty dope. Yeah. Well, as soon as it's out, we'll cover it. Yeah. You know? So, yeah, this was pretty cool.
Starting point is 01:00:36 Okay, the final thing we're going to talk about is a proposed strategy for awakening patients. Okay. With coma, right? Right. Because at the end of the day, that's what really matters. Clinically, we want to. That's how it started. And that's how we're going to end it.
Starting point is 01:00:49 So the intervention that they looked for and how to test was deep brain stimulation. This is, again, the idea of you test, you put in an electrode deep into the brain, and then you give it electrical activity, and you try to wake up the neurons. Okay. Now, the researchers here, what they did was test a bunch of targets in their biophysical model and say, what if I provide stimulation here? What if I provide stimulation here? What's the best target in my three-component model, right?
Starting point is 01:01:22 Because there's a bunch. There's cortex, there's thalamus, there's subthalamic nuclei. There's the palladium. And each of those has their own little subpopulations. So we can get really granular now, right? We can get really granular and try to think what is the best target? This is so good. They settled on the subthalamic nucleus.
Starting point is 01:01:42 It had an overwhelmingly standout result for consciousness recovery in their model. Okay. Then again, they tested this with humans. They tested 130 hertz stimulation. in the subthalamic nucleus in six awake human patients, and the cortical CNN, the cortical consciousness detector that they had previously trained, detected a significant shift towards optimal consciousness.
Starting point is 01:02:13 This is crazy. With only stimulation in the STN. If they went anywhere else, only the subtylamic nucleus showed this effect. If they did it in the cortex, if they did it in the palladium, didn't show any significant increase in consciousness. Yes.
Starting point is 01:02:27 And that's what the model predicted. So are you saying we found the boss's office? Yeah, it seems we found... We may have found the boss's office. Where if you turn the lights on and off, the boss will wake up. Right. Right. Right. This is, I'm so mad because it's so clever. Each of the three layers also on how we went through it of like detection, characterization,
Starting point is 01:02:49 and evaluation almost is like is so... good? No. Because I think the part that's getting me about this piece is because you've set up like the genomic algorithm and the model, the brain simulator, the way they thought to set it up that way means that you almost have this like alpha fold adjacent kind of thing where you can in silica, like test stuff to try to narrow the sandbox of where where to look.
Starting point is 01:03:23 Exactly. Right? And like that's so valuable. Yeah. Yeah, exactly. It doesn't necessarily have to be the exact answer. No. But if it's even somewhat directionally correct, that's unbelievably valuable.
Starting point is 01:03:35 Yeah, dude, it's great. And one thing that one thing that's kind of funny is so Daniel, he is himself a science communicator, right? So he's got an Instagram and a TikTok. And he did like a short three minute video being like, hey, my paper came out and he kind of explained it at a very high level. I mean, here we've gone really. in depth. So at that
Starting point is 01:03:54 high level he was describing his generative AI framework and there was someone in the comment who was like, that's not really AI right, because you're using a biophysical model and it's like, dude, that's the point. That's the point. It's like without a biophysical model, I wouldn't be able to make these predictions of
Starting point is 01:04:10 oh, it's the PV plus neurons and the cortex. It's this highway in between the striatum and the palladium. It's the subthalamic nucleus that we need to probe. It's just going to be some random neuron. in some random layer of a trillion parameter model. What good is that?
Starting point is 01:04:28 100%. I still come back to one of the, there's so many interesting insights in this entire paper's architecture, like the experimental design architecture. But I think a key piece was you can get traceability and then subsequently reproducibility because of that brain simulator. Yeah.
Starting point is 01:04:50 Like and the way in which it is Explicit. It is What's the there's the the terminology and this may not be correct. There's a terminology where a Probabilistic versus deterministic and it's more on the deterministic side and less on the probabilistic side. Yeah. Yeah. Which in science That's a good thing. It's a good thing. Yeah. It's very much a good thing and right and then finally we now have an idea that it should be the sub-delimic nucleus that we target which is the this tiny, like, lentil-sized structure, right? It's actually also quite incredible, if you think about it, like, that is the boss's office. Right.
Starting point is 01:05:29 Right. For at least stimulation of the brain. Consciousness could be a distributive thing, but just stimulating that tiny structure of maybe, let's say, hundreds of thousands of neurons at the max, is going to wake up a brain that is 86 billion neurons, right? Consciousness is a crazy thing. We're getting closer. So with actually a correct analysis, because there's going to be probably some thoughts about, oh, like consciousness is a, like you discussed at the beginning, a very expansive thing.
Starting point is 01:06:02 And really all we're identifying in this last piece is, I keep using the grill lighter example. This might just be the igniter, the little button you press on the grill to turn consciousness on. Yeah. But that's that's all we're saying. I don't know what the grill being on means. Right. We don't know how big the grill is. Is it a black stone?
Starting point is 01:06:24 Yeah. Is it a, you know, whatever. Exactly. We're just saying we may have found where we can wake. Yes. An unconscious from this vegetative or unconscious state. Yes. And the interesting dovetail of how the 2007 paper we talked about that identified this idea of minimally waking consciousness.
Starting point is 01:06:48 was actually a key step in order for this to actually also work. Because that was where we started to zoom in and be able to validate the mesocentric model. It's just like everything has to... Study and play. Come together on a Windows 11 PC. And for a limited time, college students get the best of both worlds.
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Starting point is 01:08:00 Hasbro is not a sponsor of this promotion. Yeah, one after the other. It has to stack, right? Yeah. In order for this to even be possible, this is really quite nice. It was a good paper. Daniel does a lot of really cool work with Koma.
Starting point is 01:08:15 He's actually also an organoid lab at UCLA. So one of these days, you know, we'll come by UCLA and see your lab, Daniel. Yes. But until then, nicely done. Very, very nicely done. Obviously, the, this is early. Yes. But there's a huge, the unlocks that are there.
Starting point is 01:08:34 You know, you could talk about it forever just in terms of not only the clinical or medical context, but even for the philosophy of mind kind of stuff, having some mechanistic details. Yes, that's big. And I think, I think the part that is going to be most influential for this paper is actually the, the way that he went about using this biophysical model. Yes, I totally agree. And tweaking. I totally agree.
Starting point is 01:09:05 That's a very interesting way to do things. I totally agree. And I can already imagine it being used for all sorts of stuff. material science, like physical things, you know? Like we've got really good models about how atoms work with each other. Exactly. Make a GAN genetic network type thing. You know, like that is the part that is really, like I think mechanistically very interesting
Starting point is 01:09:30 than me. The methods is very nice. I mean, obviously the results are incredible, but to me, the one I'm most impressed about is the way that he used this biophysical model. As someone who's coming more from the technology and software world, it is naturally what I'm able to better engage in at a deep level. But I agree with you. I think they've basically created a conceptual framework around how to design ML and AI architecture as an end-to-end system. and process that is subject matter agnostic.
Starting point is 01:10:16 Yeah, yeah. Like it could work. Yeah, yeah, yeah. That thing can work. And the whole variety of the brain was just the first target. But the exact same conceptual framework could work in a variety of different areas. Yeah. Particularly the data feedback loop and validation, processing, et cetera.
Starting point is 01:10:31 Really, really, I just, this was great. Yeah, good stuff. Well done. Daniel Toker at all. Again, this was in Nature Neuroscience on March 12. 24th, fresh hot off the presses. Again, there is nowhere else on the internet, not even on the direct pages of the authors themselves
Starting point is 01:10:49 where you're going to get this level of excitement, passion, and deep dive. They need a break. Daniel needs a break anyway, so he doesn't need to. It's our job to do this and step in. Yeah, we'll see what he thinks about. You actually, guys, did pretty well. You did pretty well.
Starting point is 01:11:04 Just another fantastic paper. And we just really want to thank those of you who have stayed this long and listened to the episode for staying with us and enjoying this journey of curiosity and discovery. I will do a brief pause to ask if we would like to do a comment. For the audience. Yeah, GAN.
Starting point is 01:11:27 GAN. This has become our shtick. We can't think of anything. What's another alternate full form of GAN? Yeah, acronym. generation for generative adversarial networks. Come on, you guys can think of something better. Something great. We really appreciate you all. My name is Lester Nare, joined as always by my co-host and our resident PhD Krishna Chowdery. This is the last reminder I'll make on this. We are moving to single story episodes multiple times a week. We have gotten confirmation from our deep listeners that you do appreciate it and you like it. And there was a good idea that we will think through. I don't know if actually, I don't even know, actually, I don't know, you know, if you saw this. Yeah, yeah, yeah. The rundown, when we do the rundown at the end of the week,
Starting point is 01:12:13 we don't really go in depth. And there's a lot of folks who would like us to go in depth or any number of those particular stories. So we will look into having basically a patron system to vote on what rundown story should we follow up on for a deep dive. It's a great idea. Excuse me for not remembering the commenter who said it, but you can comment again. We do see it. Thank you so much. We will see you all later this week. comes in all shapes and sizes. At First Citizens Bank, we roll with your goals
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