Exploring Consciousness with George Mashour

What is consciousness? Neil deGrasse Tyson and Chuck Nice learn about the study of consciousness and how psychedelics could uncover the inner mechanisms of the brain with anesthesiologist and founder of the Michigan Psychedelic Center, George Mashour.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Chuck Nice?

  Anybody who's seen a picture of themselves for real understands that instruments that measure of reality objectively can really mess you up. I see a picture of me and I'm like, I do not look, I'm not this ugly. I am not this ugly. But that is because when I look in the mirror, my brain is creating a construct for what it says, this is what I look like. But the camera is just like, nah, you ugly, bro. Sorry.

• 0:29Neil deGrasse Tyson?

  Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:42Neil deGrasse Tyson?

  This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. Got Chuck with me. Chuck Nice, how you doing, man?

• 0:49Chuck Nice?

  Hey, doing well, Neil. Thank you for asking.

• 0:52Neil deGrasse Tyson?

  We got a hot topic today. Psychedelics and consciousness.

• 0:55Chuck Nice?

  Ooh. Well, guess what? One of them I really, I'm interested in.

• 1:02Neil deGrasse Tyson?

  Okay.

• 1:03Chuck Nice?

  I'm interested in one of those things.

• 1:05Neil deGrasse Tyson?

  One of them, okay. We have our expert about town on this very subject. He's been on StarTalk before. George Mesher, did I pronounce your name correctly, George?

• 1:16Speaker 02

  Yes, you did. Thank you.

• 1:18Neil deGrasse Tyson?

  Excellent. A chair of anesthesiology? And professor of neurosurgery, University of Michigan? You've taken a multidisciplinary approach to consciousness? I have a zillion questions about that. And the network mechanisms that empower consciousness? And possibly disrupt unconsciousness?

• 1:38Chuck Nice?

  Yeah.

• 1:38Neil deGrasse Tyson?

  And just all kinds of metrics of consciousness? You're the guy.

• 1:43Chuck Nice?

  Is that, is that what made you want to be an anesthesiologist? Or was it the other way around? Was being an anesthesiologist just sparking all kinds of curiosity about consciousness? Or was it that you always had these wanderings about consciousness and that led you to being an anesthesiologist?

• 2:03Speaker 02

  Yeah, great question. I got interested in consciousness studying philosophy as an undergraduate. And decided to pursue medicine and neuroscience. Actually started off in psychiatry with an interest in psychoanalysis. And then I switched over into anesthesiology because I thought that would be the best field to study consciousness because of the Rich set of tools that we have to modulate conscious experience.

• 2:31Chuck Nice?

  Not to mention the myriad of either willing or unwilling subjects.

• 2:40Neil deGrasse Tyson?

  George, I like your phrase to modulate their conscious experience. You mean knock them out. Just say it.

• 2:47Speaker 02

  Well, but actually it depends because there are certain procedures in which you try to engineer the state, if you will, to be somewhere in between consciousness and unconsciousness.

• 2:59Neil deGrasse Tyson?

  And also this affects very real afflictions, nerve injury that people have, stroke. And so, yeah, so let's get, let's get right into this. So you founded the Michigan Psychedelic Center beyond everything we just said. Because regular consciousness was not good enough for you.

• 3:21Chuck Nice?

  Yeah, exactly.

• 3:23Speaker 02

  I started off studying consciousness. I founded the Center for Consciousness Science here at the University of Michigan Medical School in 2014. And we used anesthetics as a tool to modulate the level of consciousness. That's one key dimension of consciousness. And the level of consciousness refers to the global state of arousal. So I'm awake, somnolent, sleeping, anesthetized, comatose, brain dead.

• 3:53Speaker 02

  And it's a very powerful set of tools that we have, but it's also limited because it isn't really addressing another key dimension of consciousness that is sometimes referred to as the content of consciousness. That's what we're actually experiencing, the qualitative aspects, the redness of the rose, the blueness of the sky. And this is where psychedelics can come into play because they don't have a major impact on the level of consciousness, but they certainly alter the way that we experience things and the content of consciousness. And that's what motivated it.

• 4:28Neil deGrasse Tyson?

  That's a whole other place to go. Oh, my gosh.

• 4:30Chuck Nice?

  Yeah.

• 4:31Neil deGrasse Tyson?

  On the research frontier. So consciousness then.

• 4:37Neil deGrasse Tyson?

  If I thought about it mathematically, another dimension of consciousness is the intensity with which you experience reality. Is that a fair way to say that?

• 4:45Speaker 02

  Um, yes, I think that would, uh, fall under that content of consciousness. And there are a lot of different levels that we could be talking about, just basic interoceptive consciousness, consciousness of the world, consciousness of myself or self-awareness.

• 5:02Neil deGrasse Tyson?

  Alright, so, and, and tell me, in the, the extreme limit of these examples here, you, you mentioned comatose. The, uh, what do people mean when they say it was a medically-induced coma? Can you measure that as like the extreme limit of no consciousness without being dead?

• 5:20Speaker 02

  Sure. So, I mean, one form of the medically-induced coma or a common form would involve some sort of anesthetic agent like a berbaturate or propofol, for example, these intravenous anesthetics. You can, uh, in fact, measure the state or at least the drug impact, uh, using the electroencephalogram, EEG, focused on brainwaves. And there are certain, uh, characteristic morphologies such as something called burst suppression, which is electrical quiescence punctuated by this high-frequency, high-amplitude activity. That would suggest that somebody does not, does not

• 6:03Speaker 02

  have the capacity for consciousness. So I think that would be one example of, uh, what is referred to as a medically-induced coma.

• 6:11Chuck Nice?

  Speaking of measuring, what exactly are you measuring, uh, electrically? Is it the firing of neurons in a certain part of the brain? Like, what exactly is the metric?

• 6:25Speaker 02

  Yeah, that, that's a great question. First of all, I want to be clear that even though we're measuring things, not everything is reducible to a single metric.

• 6:34Speaker 02

  Or measurement. And Chuck, to your question, it really depends on the scale. It depends on the experimental setting. So in the laboratory, we might be able to measure neuronal activity at a single unit level. For example, in the non-human primate brain, which we've done in our research group with our collaborators. In humans, we're going to be using typically scalp EEG to measure electrical activity. There's also magnetoencephalography that's measuring magnetic waves. There's functional magnetic resonance imaging, which is a neuroimaging form. So there are a variety of different scales and neuroimaging techniques that people evaluate

• 7:16Speaker 02

  when they're trying to assess an impact of a drug, for example, on consciousness. And then a whole suite of analytic techniques thereafter to try to parse through that data.

• 7:30Neil deGrasse Tyson?

  So now, let's back up. Let me be the thousandth person to ask you. What is consciousness? How should we think about it?

• 7:42Speaker 02

  Yeah, great, great question. I don't know if I can really give you an answer, but on the other hand, it's something that we all know from the first-person perspective. It's a sense of experience, subjectivity, interiority, a point of view. Some people have defined it operationally. One philosopher is what we lose at night when we go into a dreamless sleep and what we regain the next morning when we wake up. Oftentimes, in the clinical setting, we have to operationalize this through behavioral assessments. Neil, Chuck, I don't have access to your first-person phenomenology, but I can make some inferences

• 8:26Speaker 02

  about your state of consciousness based on your interactivity. And we do this all day. We basically are making inferences about the state of someone else's subjectivity based on their objective behavior. That usually works, but there are certain situations, certainly in medicine, where there can be a divergence between responsiveness and consciousness.

• 8:52Neil deGrasse Tyson?

  So the fact that the bookshelves are filled with people writing with titles, "Consciousness Explained," for example, doesn't that mean we don't really understand consciousness? As long as people continue to write books on it? Because I can tell you that in physics, you know, there's like three books on gravity on the shelf, right? We're not still writing books on Newton's laws of gravity. So, so we're done there and we're on to other things. So isn't the activity in the field a measure of how much we don't know more than a measure of how much we do?

• 9:27Speaker 02

  Yeah, I think that's fair to say, and certainly if you compare it to physics and the long history of physics, or other disciplines, the modern science of consciousness as we know it, and we talk about it, really started to coalesce in the 1990s. Now, of course, people have been asking the question, "Why are we aware of ourselves and the world?" Since people have been able to ask questions. But in terms of the modern science, it really started to emerge in the 1990s. For most of the 20th century, consciousness was really marginalized, even delegitimized, as a topic of scientific inquiry, largely through the influence of behaviorism and psychoanalysis.

• 10:12Speaker 02

  But then in the 1980s, there were some-

• 10:14Neil deGrasse Tyson?

  Freud, say it, say it, Freud.

• 10:16Speaker 02

  That's all right, you said it, that's fine.

• 10:18Chuck Nice?

  Yeah. Tell me, tell me how you really feel about your mom and cocaine.

• 10:24Neil deGrasse Tyson?

  And cigars, and cigars.

• 10:26Chuck Nice?

  Right, yes.

• 10:28Speaker 02

  I'm not going to address that, but, uh, many implications. But actually, yeah, so Freud said that consciousness is merely the tip of the iceberg, and probably was correct in terms of how much cognitive activity is going on outside of our conscious realm. But in the 1980s, there were some really prominent scientists and intellectuals that started to publicly turn their attention to consciousness. Nobel laureate Francis Crick, Nobel laureate Gerald Edelman.

• 10:59Speaker 02

  Won the Nobel Prize for his work in immunology. Mathematical physicist Roger Penrose, who won the Nobel Prize a few years ago.

• 11:08Neil deGrasse Tyson?

  Not for that.

• 11:10Speaker 02

  I know, I know, and I know I don't need to tell you this. I believe for his work on black holes.

• 11:15Neil deGrasse Tyson?

  Yeah, yes.

• 11:16Speaker 02

  But they started to turn their attention to this in a public way, and that helped to confer legitimacy. So it's fairly young, and despite the fact that we're learning a lot, and neuroscience has really advanced in terms of neuroimaging, the ability to manipulate neural circuits to image them at the animal level, we're still asking fundamental questions like,

• 11:44Neil deGrasse Tyson?

  Right, there it is.

• 11:45Speaker 02

  Are the neural correlates of consciousness in the front of the brain or in the back of the brain? Literally.

• 11:51Chuck Nice?

  Where is consciousness located?

• 11:52Speaker 02

  That course in terms of large swaths of cortex. And most recently, there's been a big kerfuffle in the field with respect to one very well-developed theory of consciousness that has been called out or accused by 124 individuals of being pseudoscience. And this is a theory that's been around for almost two decades. So it just gives you a sense of the state of the field. It is, relatively speaking, in its nascent phases, certainly compared to disciplines such as physics.

• 12:32Neil deGrasse Tyson?

  So then you'd expect there to be, it's the Wild West, and that's not a bad thing, it's just the reality of a newly born field.

• 12:39Chuck Nice?

  In a way, it's kind of a cool thing.

• 12:41Neil deGrasse Tyson?

  It's kind of cool, right, right, right. So why do you, why are all these people who want to deny consciousness to other animals? Like, anyone who's owned a cat or a dog will never deny them a full consciousness of what's going on. But how about your jerk?

• 12:56Chuck Nice?

  Especially a cat. We know that cats, now dogs, okay, listen.

• 13:01Neil deGrasse Tyson?

  Yeah, the cat's plotting, plotting your death.

• 13:04Chuck Nice?

  When you see that cat actually calling your lawyer to see if it is a beneficiary on your insurance, you know that that cat is conscious.

• 13:15Neil deGrasse Tyson?

  That's right. Basically what they're doing. So, so what is, where does that come from? Is it the size of our frontal lobe? Relative to that of other animals, because we all know cats don't have a forehead, right? So, uh, so what?

• 13:30Speaker 02

  Yeah, that is, that is such a great question, and that, that taps into this bigger question, and I've alluded to it earlier, which is, how do we know someone or something is conscious or not? So on the one hand, you have some who would assert that only human beings are capable of consciousness, and again, this is where definition is important, because some people might actually be referring to self-awareness. There, there are others, and not just in the philosophical realm, but in the neuroscientific realm, who are bordering more on what is called panpsychism, which suggests that everything in the universe, to some degree, has some level of consciousness.

• 14:14Chuck Nice?

  That's, that's like a molecular consciousness.

• 14:17Speaker 02

  Yeah, so how do we, um, how do we figure this out? And you brought up animals as kind of an example and between. Well, this is where it's really important for us as a field to try to identify, and some are trying to do this, you know, what are the fundamental characteristics of a conscious system that we can measure independently of behavior? Um, because again, we're making inferences based on behavior. Even if you're describing your interaction with a, a dog or a cat, you're making inference based on their behavior. But how can we figure out a behavior-independent way to assess the system's capacity for consciousness?

• 14:58Speaker 02

  Because then we could apply that to someone who, for example, we think is in a vegetative state, but might not be, or somebody that we think is anesthetized in the operating room, but they're only paralyzed.

• 15:11Chuck Nice?

  Right.

• 15:12Speaker 02

  Or a species that can't communicate with us, or babies.

• 15:17Chuck Nice?

  I was gonna say, because really where you need to go first is babies, because their consciousness, uh, is emerging, I don't know if it's emergent, because that would be all of us.

• 15:28Neil deGrasse Tyson?

  It's a different word, yeah.

• 15:29Chuck Nice?

  It's a different word, but it is emerging, because when you have an infant... You couldn't necessarily say that that infant is conscious of the world around it, is conscious or aware of itself. But you know that as another human being, that it is definitely going to be that barring any kind of brain malady or cataclysmic event that would stop it from happening.

• 15:55Speaker 02

  Yeah, and you could take it even, or you can take that question even earlier and think about the prenatal and utero phase where there is electrical activity, where there are dynamics of brain activity that might potentially sustain experience. And obviously, this is a question with major ethical implications as well. The other, the other place where this is going to come up, so, you know, the big problem used to be, we think someone is unconscious because of their behavior, they're unresponsive, but they're actually conscious. And I gave you an example, someone we think is anesthetized

• 16:36Speaker 02

  or we think is in a vegetative state. But now, there's another problem that's emerging, or that will emerge, and that is, now we have artificial systems that are highly responsive, and will get more and more responsive, and now people are going to start asking the question, well, is this responsiveness driven in part by some kind of sentience? And again, that's where we need these tools to assess, does this system in a principled way have the capacity for consciousness?

• 17:08Neil deGrasse Tyson?

  We're all gonna die when AI takes over.

• 17:13Chuck Nice?

  That's it.

• 17:14Neil deGrasse Tyson?

  That's the answer to all those questions.

• 17:27Speaker 03

  Hi, I'm Chris Cohen from Hallworth, New Jersey, and I support StarTalk on Patreon. Please enjoy this episode of StarTalk Radio with your and my favorite personal astrophysicist, Neil deGrasse Tyson.

• 17:46Neil deGrasse Tyson?

  Tell me about the importance, because I've read papers on this, the importance to you as a neuroscientist and a consciousness expert of an animal recognizing itself in a mirror.

• 18:00Speaker 02

  Yes, so I mean, this is something that goes back to Darwin, who, while he was thinking and theorizing and investigating biological evolution, was also thinking about cognitive and mental evolution. And that mirror recognition test has often been used, and I'm not an expert in that, so I want to be clear about this, to assess some sort of self-reference, self-recognition. And this is interesting in terms of applying it to not just primates, but also some avian species.

• 18:45Speaker 02

  And, you know, some would posit that there have been multiple lines of evolution, not exactly the same thing as the cortex as we know it, the avian pallium, but a kind of similar functional organization. So I think this comes up in terms of trying to identify, you know, where across the timeline of phylogeny did consciousness emerge? And the other question is, is it an all-or-none phenomenon? Is it graded? Is there a continuum?

• 19:17Chuck Nice?

  Because, I mean, think about it. If a bird may see itself in a mirror and go, "Oh, that's not another bird, you know, that's just me." But that doesn't mean that it then ponders why it is here.

• 19:32Neil deGrasse Tyson?

  Its own existence, yeah.

• 19:33Chuck Nice?

  Its own existence, you know. So, you know, some of this is a matter of intelligence as opposed to consciousness.

• 19:42Speaker 02

  Yes, it could be. And actually, your comment Chuck also leads to a reflection on different categories of consciousness theories. Because some theories are referred to as perceptual, others are cognitive. And one question that comes up is,

• 20:01Neil deGrasse Tyson?

  Interesting.

• 20:01Speaker 02

  Does consciousness itself require some of the cognitive functions that we have, such as attention or working memory? Or is it just kind of a purely perceptive phenomenon?

• 20:15Chuck Nice?

  Oh, let's talk about getting high.

• 20:18Neil deGrasse Tyson?

  Well, I'll get to that in a minute, just a quick second here. Hold on, but I've been saving that for the end of this conversation.

• 20:24Chuck Nice?

  I'm just sitting here just like, when are we getting to it?

• 20:27Neil deGrasse Tyson?

  I want to get the foundations established here.

• 20:31Chuck Nice?

  That's why you're a scientist.

• 20:35Neil deGrasse Tyson?

  So if we don't really understand consciousness on a very detailed level, we're not in a position to establish that what's going on in computers is consciousness. Right? Can we? Are your tools useful, even if we don't know what it is that's going on, to say that a computer has achieved consciousness?

• 21:02Chuck Nice?

  Right, how will we know?

• 21:04Speaker 02

  Well, that's the question. When people say, when people will ask me, do you think computers are or can be conscious? My response is, how will we know? And again, that's where we need to figure out what is the system that's required? And does that system need to be neural? Does it need to be neurobiological? Or can you simply have a functional arrangement of information processors that could achieve the same outcome? So I would say we do not know that.

• 21:35Chuck Nice?

  So let me ask you this then, based on what Neil just asked and what you just said. If we were, have the computing power, like a quantum computer, and we were able to replicate Down to the very neuron, a human brain. So you have this trillion connections, all firing at once. And, and you're able to program into it exactly everything that, uh, the person that you're mapping was thinking and so forth. Would that then be sentient? Or would that just be a replication of sentient?

• 22:14Speaker 02

  It's a great question, and I don't have an answer.

• 22:17Neil deGrasse Tyson?

  Chuck, you're not supposed to stump the guests, okay? That's not why you're on the show.

• 22:22Speaker 02

  No, it's great, yeah, great to explore. Um, and you know, there, there are a few things that go along with that. One is, you know, we think about it exclusively related to the brain. But what about, what about the body? What about the interaction with the environment? So those environmental factors are critically important as well. But also to the point is, you know, we don't know yet what is generating the conscious experience. And we can look at lots of different network models. Um, and we can look at different principles across different systems, but some of these systems are conscious and others aren't. So there, there are clear network phenomena that are going on in the conscious brain

• 23:05Speaker 02

  that get disrupted during unconsciousness. But there's similar network phenomena going on in non-biological systems that we don't think are conscious. So, very important question.

• 23:18Neil deGrasse Tyson?

  And Richard Hofstadter, was that his name, or Douglas Hofstadter? Who, who wrote, uh, Gödel, Escher, Bach, do you remember?

• 23:24Speaker 02

  Yes.

• 23:25Neil deGrasse Tyson?

  Last name's Hofstadter. Uh, in that book, which I think won a Pulitzer Prize, very thick, very fascinating book. Uh, in the end, he has a conversation with Einstein's brain. And he imagines, this is, this is like decades before people thought of that we're in a simulation or anything. He imagined removing Einstein's brain, but preserving every single neuro synaptic, um, capacity, all the neuro synaptic capacity of that brain. Okay? So it's in a jar. And so now you ask it a question. You say, Albert, um, you know, what time does Grand Central Station arrive at the next train? Okay? That'd be like a fun relativity question.

• 24:09Neil deGrasse Tyson?

  Cause everything's relative, right? So you pick a question, and then that question. Goes in through acoustic signals to the up to the to the whatever the acoustic nerves that connect with the brain and you watch it trip circuits throughout the brain. And if you had it perfectly modeled, you should be able to follow how that question lands and how it triggers a response where then Einstein's brain speaks back. Is that in principle, something that could happen one day, do you think?

• 24:47Speaker 02

  Yeah, I mean, you know, I don't know if I'm answering your question, but first of all, you know, this brain in a vat concept really in many respects goes back to Descartes when he was reflecting on whether he could just be completely deceived by everything that he was experiencing. But yes, there are ways of mapping the information processing from, as you said, the primary, in this case auditory cortex to higher order cortices. These different volleys or reverberations of activity can in coarse ways be mapped.

• 25:29Speaker 02

  But then again, the question comes up, is that associated with experience? Because I could, I can put the same questions into ChatGPT right now. That's going to have its own processing capability and it could give me the same answer as Einstein's brain in this thought experiment through a completely different mechanism that we presume is non-conscious.

• 25:51Neil deGrasse Tyson?

  Got it, got it. Okay, very good. All right, so now let's get to the meat of this conversation. Sorry, there could be vegetarians out there. Let's get to the carrots of this conversation. I never thought before today and the notes for this conversation, how psychedelics could be.

• 26:31Neil deGrasse Tyson?

  Tools in your utility belt to probe the conscious mind. And that fascinates me greatly. So you would measure certain quantities of psychedelics. And get a willing subject to ingest them. And then measure the consequences of that. And their awareness and reaction to the physical world around them. So that seems like an entirely. Is that an unexplored frontier for the neuroscientist? As opposed to just the person who wants drug experiences?

• 27:09Speaker 02

  Yes, great question. So obviously, many of these naturally occurring psychedelics have been used for millennia in spiritual practices and rituals. But of course, there was already in Western civilization, a first wave of intense interest in psychedelics as a tool to understand the mind, the brain, and for therapeutic purposes. And this is something that was happening in the 1950s and 60s. And of course, we know how that turned out. In terms of the late 60s, the enthusiasm started to extend far beyond the rigor and sense of responsibility.

• 27:51Neil deGrasse Tyson?

  Woodstock, just say it, Woodstock.

• 27:53Speaker 02

  Things were made illegal around 1970. And then the field really just became dormant.

• 28:01Neil deGrasse Tyson?

  It was under President Nixon, if I remember correctly. The drug rules got all readjusted.

• 28:07Speaker 02

  Right.

• 28:08Neil deGrasse Tyson?

  Yeah.

• 28:09Speaker 02

  Yeah. And now we are really experiencing what has been referred to as the psychedelic Renaissance. Because in the past 10 to 15 years, there's been a resurgence of neuroscientific investigation.

• 28:25Speaker 02

  There has been a resurgence of clinical investigation with rigorous clinical trials that are testing psychedelics for conditions like depression. These articles are getting published in the New England Journal, The Lancet, major medical journals in the field. And obviously, social attitudes have been changing, policy has been changing with decriminalization, and cannabis has probably led the way a bit on this. So we really are in the midst of a renaissance. Again, this is something that was already a matter of intense interest, but now we have a lot of tools, such as neuroimaging, for example, lots of analytic tools, theoretical

• 29:10Speaker 02

  constructs, to explore psychedelics and to help us understand this spectrum of conscious states. Now, I'm an anesthesiologist, and I actually, I want to state with humility that I wouldn't consider myself the foremost psychedelic neuroscientist. There are great people out there doing great work, but if you think about anesthetics and psychedelics, they're kind of mirror images of one another, and they help us probe our model of the world, brain function. So anesthetics suppress consciousness, they contract the repertoire of accessible brain states or configurations, they reduce neurophysiologic complexity.

• 29:54Speaker 02

  Psychedelics, one could say they give us a higher consciousness.

• 29:59Chuck Nice?

  Yeah.

• 30:00Speaker 02

  They expand.

• 30:01Chuck Nice?

  Elevate consciousness.

• 30:02Speaker 02

  They expand the repertoire of accessible brain states, and they enhance neurophysiologic complexity.

• 30:08Neil deGrasse Tyson?

  Wait, wait, wait, but, but, you know, the brain barely works as it is, as a measure of, as a tool to measure objective reality. You know, if it worked any, if it worked better, we wouldn't have, have optical illusions books, right? Where simple line drawings completely confound your capacity to know what is objectively true and what isn't. So.

• 30:33Chuck Nice?

  We certainly wouldn't have Penn and Teller.

• 30:35Neil deGrasse Tyson?

  Illusionists, right. That wouldn't exist, right? So, so why would stirring chemicals into the brain?

• 30:46Neil deGrasse Tyson?

  Give you a more accurate understanding of the brain rather than a less accurate one.

• 30:52Chuck Nice?

  Hmm.

• 30:53Speaker 02

  Yeah, so that great question and there are a couple of dimensions there. First of all, what is consciousness doing in the first place to your point? Is it a mirror for reality or objective reality, as you said? I don't necessarily think that's the case. There are lots of different ways that you can think about it. You can think about the brain as a sensory processing organ. But others would suggest that the brain is really creating this conscious experience. It helps us get through the world, helps us achieve the biological goals. And the brain is essentially like a hypothesis and model making machine. It generates a mental model.

• 31:36Speaker 02

  It uses sensory information to give feedback to that model. So I think what what the drugs are doing in one direction or another is not so much helping us understand, you know, the brain vis a vis objective reality, but just how the brain functions in terms of its own models and its own capacity for consciousness.

• 31:59Chuck Nice?

  So it's it's.

• 32:00Neil deGrasse Tyson?

  An institute tool, an institute tool.

• 32:02Chuck Nice?

  Yeah, because that makes sense because anybody who's seen a picture of themselves for real understands that instruments that measure of reality objectively can really mess you up.

• 32:16Chuck Nice?

  Because I see a picture of me and I'm like, I do not look, I'm not this ugly. I am not this ugly. But that is because when I look in the mirror, my brain is creating a construct for what it says. This is what I look like. But the camera is just like, no, you're ugly, bro.

• 32:31Neil deGrasse Tyson?

  So Chuck, you should sign up for one of his. It sounds like you need help.

• 32:37Neil deGrasse Tyson?

  All right, so presumably the dosing matters greatly here. And if people's brains are roughly similar, you would expect similar reactions to similar drugs and perhaps similar dosing. But Mike, I bet that's not the case. Could you explain why?

• 32:57Speaker 02

  Sure, I think the dose does matter and people are exploring what is necessary, for example, for a therapeutic effect. Can you do microdosing? That doesn't really have a major impact on consciousness.

• 33:13Speaker 02

  Some actually are exploring whether you need to have a psychoactive experience at all. Maybe there are aspects of these drugs that are having a therapeutic effect independently of the psychedelic experience.

• 33:24Neil deGrasse Tyson?

  Which of course is the case with marijuana. You separate out the ingredients there and they have very different utilities.

• 33:31Speaker 02

  And that's being explored as a novel drug class. I think the other thing about psychedelics, and this goes back to the Timothy Leary days, is the concept of set and setting. That unlike other drug classes where maybe you give dose X and you get response Y, obviously it's going to vary across the population. But with psychedelics, the set or the mindset going into the experience and the setting or the environment can have a major influence on what the subjective experience is.

• 34:07Neil deGrasse Tyson?

  Of course it would.

• 34:08Speaker 02

  So even at a similar dose, in the same person, going into it, you know, in a certain mood or with a certain orientation, having this at a hospital versus a naturalistic setting could evoke very different kinds of experiences. Good trip, bad trip.

• 34:24Neil deGrasse Tyson?

  Yeah, exactly, exactly. So if you're successful, if you're supremely successful in this exercise, you and your colleagues, and I've said this, but only because it felt like it would be true, not because I really knew, if you're successful in treating mental health, we won't need psychologists or psychologists in the future, because you just go into the brain and fix the brain, rather than, oh, lay on the couch and talk to me for three hours a week and do that for three years and maybe you'll be cured. You're coming at it from a whole other place. So I've said this, I've gotten only mild pushback, because I think deep down people know it

• 35:04Neil deGrasse Tyson?

  could be true, if not will be true, that psychology is to neuroscience as alchemy is to chemistry. Oh.

• 35:13Chuck Nice?

  Well, that's not good for psychologists.

• 35:15Neil deGrasse Tyson?

  No, no, what I'm saying is you have to begin somewhere. I'm not faulting alchemists. They bet on the wrong horse, but they kept good notes.

• 35:21Chuck Nice?

  They bet on the wrong, yeah.

• 35:22Neil deGrasse Tyson?

  But they kept notes and they, the foundations of the early periodic table were there. You know, but we learned, no, there's a better way to do this, a more reliable way. So could you just react to what I just said?

• 35:34Speaker 02

  I'm reacting right now.

• 35:36Neil deGrasse Tyson?

  No.

• 35:37Speaker 02

  Um, yeah, so it's a, it's a great question. And, and another way I want to just reframe this is, you know, what is the mechanism of therapeutic action of the psychedelics? And there are a couple of different possibilities. Some would say it's just the drug in the brain. There's something that's going on at the molecular level. It's going to induce neuroplasticity, maybe dendritic spine arborization and neurons. And we can engineer a drug that doesn't even have to have any experience. Others would say, well, it's not just the drug in the brain. It's the experience that the drug evokes. And there is something that the person and the brain learns about itself through that experience, and that's essential.

• 36:20Speaker 02

  And others might say, no, it is actually the ther- it's the therapeutic intervention. It's the psychotherapy. The drug is just creating the conditions for growth, but it's the therapy that's actually doing the work. Or it might be some combination.

• 36:38Chuck Nice?

  So i- i- it's kind of, it's kind of like planting, planting a, a, a, a field. You gotta prepare the ground. You gotta have the seeds. You have to have the water. All these things come together. You know, it's not just one of those things.

• 36:52Speaker 02

  But it's, it's an, I don't know the answer, but it's an empirical question. And if we find out that these so-called non-hallucinogenic psychedelic analogues or psychoplastogens can have an impact on depression.

• 37:07Speaker 02

  Without any therapy and without any associated psychedelic experience, that would help us answer.

• 37:14Chuck Nice?

  We are seeing some evidence, not necessarily of that per se, but there is some evidence pointing towards that. When you look at PTSD patients who go through these psychedelic experiences, many of them basically say, "I don't have PTSD anymore."

• 37:31Speaker 02

  Yes. Well, there certainly is empirical evidence that some of the protocols used in these trials, which often include a psychedelic drug support during the psychedelic experience and then psychotherapy or integration afterwards, are effective. And what's unique, I think, and what differentiates psychedelics from traditional antidepressant medications is that they can sometimes have an impact that's durable beyond the drug being in your body.

• 38:01Chuck Nice?

  I was gonna ask that, yeah.

• 38:02Speaker 02

  After a single session. As opposed to a traditional antidepressant might take four to six weeks for a mood effect, psilocybin or ketamine, it's almost immediate. And that's important if you think about somebody who's acutely suicidal or who might be in a palliative care situation with cancer.

• 38:22Chuck Nice?

  That's the other area where these cancer patients go through these psychedelic experiences and they come out of it and invariably they come out and say, "I'm cool now. I'm not afraid to die anymore. I'm no longer overly anxious or no longer anguish about the fact that I know I have a terminal disease." That's incredible.

• 38:44Speaker 02

  Yes, and that is one area trying to treat or help existential distress in the dying process. Again, was explored in the 1960s is being actively explored again with psychedelics.

• 39:00Chuck Nice?

  Wow.

• 39:01Neil deGrasse Tyson?

  So I'm delighted to just bear witness to the birth of a field and watching this unfold in real time, right in front of our eyes. And I have friends who were microdosing and who had neurological, emotional challenges, and they only speak highly of that experience. And so to the extent that science continues with Phase 1, 2, 3 trials, whatever is necessary in the field, I look forward to where this is going.

• 39:33Chuck Nice?

  Yeah, yeah.

• 39:34Neil deGrasse Tyson?

  George.

• 39:34Chuck Nice?

  Now, Doc, I gotta ask you, and this is the most important question.

• 39:39Neil deGrasse Tyson?

  And we gotta wrap.

• 39:39Chuck Nice?

  Okay, well, then I'm glad I'm getting this question in, because it's seriously important. Okay. Where do I get these drugs?

• 39:48Neil deGrasse Tyson?

  What's that?

• 39:49Speaker 02

  He's got a van out back. A good time to wrap up.

• 39:56Neil deGrasse Tyson?

  Offline, we will learn where.

• 40:02Speaker 02

  I do need to say, and this is important, that, you know, we are really trying to adhere to the most rigorous, the most responsible standards in our work. I'm looking at the big picture and the long game. It's great to be enthusiastic, but we also have to be self-critical if we want this to become part of mainstream medicine. And so my tagline always is, we shouldn't stigmatize psychedelic research, neither should we romanticize it. We need to treat this with seriousness, just like we would any other drug research.

• 40:34Chuck Nice?

  That is.

• 40:34Neil deGrasse Tyson?

  That is a sentence to end a show on, right there.

• 40:37Chuck Nice?

  If I ever heard one.

• 40:38Neil deGrasse Tyson?

  Yeah. Dr. George Mashour, thanks for being back on StarTalk. Thank you for having me. Been a delight to catch up on what you're doing in your field, you and your colleagues, and keep up the good work. Like I said, that's a whole, we're witnessing the birth of a branch of science that could just become commonplace and routine in the decades to come.

• 40:59Chuck Nice?

  And please, send me an email on where I can get those drugs.

• 41:02Neil deGrasse Tyson?

  Send me a sample.

• 41:07Neil deGrasse Tyson?

  Chuck, let's end this before Chuck loses it. All right, well, this has been StarTalk. Neil deGrasse Tyson here, your personal astrophysicist, all about psychedelics and consciousness. Again, Doc, thanks for being on the show. Chuck, always good to have you, man. Always a pleasure. All right, Neil deGrasse Tyson here, as always. Keep looking up.