The following is a conversation with Andrew Huberman, his second time on the podcast. He's a neuroscientist at Stanford, a world-class researcher and educator, and now he has a new podcast on YouTube and all the usual places called Huberman Lab that I can't recommend highly enough. Quick mention of our sponsors.

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And I'm pretty sure Andrew will have a neuroscience masterclass on there soon enough, though his podcast is basically a weekly masterclass in itself. As a side note, let me say that Andrew is a friend and a new collaborator. We're working on a paper together about a topic we're both really passionate about.

At the intersection of neuroscience and machine learning. But that's probably many months away from being published. Still, I'm really excited about this work. He's one of the smartest and kindest people I have the pleasure of talking to on this podcast. So I hope we'll talk many more times in the future.

If you enjoy this thing, subscribe on YouTube, review it on our podcast, follow on Spotify, support it on Patreon, or connect with me on Twitter @LexFriedman. And now, here's my conversation with Andrew Huberman. Why do humans need sleep? Let's go with a big first question. - Okay, well, the answer I'll start with is the one that I always default to when there's a why question.

I wasn't consulted at the design phase. So I wriggle my way out of giving a absolute answer, right? But there's one mechanism that's very clear, that's super important, which is that the longer we are awake, the more adenosine accumulates in our brain. And adenosine binds to adenosine receptors, no surprise there.

And it creates the feeling of sleepiness, independent of time of day or night. So there are two mechanisms. One is we get sleepy as adenosine accumulates. The longer we've been awake, the more adenosine is accumulated in our system. But how sleepy we get for a given amount of adenosine depends on where we are in this so-called circadian cycle.

And the circadian cycle is just this very, very well-conserved oscillation. It's a temperature oscillation where you go from a low point. Typically, if you're awake during the day and you're asleep at night, your lowest temperature point will be like 3 a.m., 4 a.m., and then your temperature will start to creep up as you wake up in the morning, and then it'll peak in the late afternoon, and then it'll start to drop again toward the evening, and then you get sleep again.

That oscillation in temperature takes 24 hours. - Plus or minus. - Temperature. - Yeah, plus or minus an hour. And I don't, even though I wasn't consulted at the design phase, I do not think it's a coincidence that it's aligned to the 24-hour spin of the earth on its axis, and the fact that we tend to be bathed in sunlight for a portion of that spin, and in darkness for the other portion of that spin.

So there are two mechanisms, the Adenosine accumulation and the Circadian time point that we happen to be at, and those converge to create a sense of sleepiness, a wakefulness. The simple way to reveal these two mechanisms, to uncouple them, is stay up for 24 hours, and you will find that even though you've been, let's say you stay up midnight, 2 a.m., 3 a.m., provided you're on a regular schedule, like that I follow, not like the kind that you follow, you get, I will get very sleepy around 3, 4 a.m., but then around 5 or 6 or 7 a.m., which is my normal wake up time, I'll start to feel more alert, even though Adenosine has been accumulating further.

So Adenosine is higher for me, the longer I stay up, and yet I feel more alert than I did a few hours ago, and that's because these are two interacting forces. So Adenosine makes you sleepy, and then just how sleepy or how awake you feel also depends on where you are in this temperature oscillation that takes 24 hours.

- Okay, so that's fascinating. So there's a bunch of oscillations going on, and then they kind of, through the evolutionary process, have evolved to all be aligned somewhat, and they interplay. So you said your body temperature goes up and down, there's chemicals in your brain that oscillate, and then there's the actual oscillation of the sun in the sky.

So all of that together has some impact on each other, and somehow that all results in us wanting to go to sleep every night. - Right, and we can get right into the meat of this, I guess we just dove right in. The temperature oscillation is the effector of the circadian clock.

So every cell in our body has a 24-hour rhythm that's dictated by genes like clock, per, b-mal. This is one of the great successes of biology, they give a Nobel Prize to Ruppert, I don't know if Ruppert got it, forgive me, but sorry, if you got it, Steve, congratulations, if you didn't, I'm sorry, I wasn't on the committee.

Nonetheless, did beautiful work, Steve Ruppert and others, but Mike Roshbosch and like other people worked out these mechanisms in flies, in bacteria, in mammals, there are these genes that create 24-hour oscillations in gene expression, et cetera, in every cell of our body. But what aligns those is a signal from the master circadian clock, which sits right above the roof of the mouth, called the suprachiasmatic nucleus, and that clock synchronizes all the clocks of the body to this general temperature rhythm by way of controlling systemic temperature, which makes perfect sense.

If you want to create a general oscillation in all the tissues and organs of the body, use temperature. And so that work on temperature, if people want to explore it further, was Joe Takahashi, who was at Northwestern now, at UT Southwestern in Dallas. And it is absolutely clear that humans do better on a diurnal schedule, sorry Lex, than a nocturnal schedule.

Because you could say, well, provided I sleep and push adenosine back downhill, which is what happens when we sleep, adenosine is then reduced, and provided I am on more or less a 24-hour schedule, why should it matter that I'm awake when the sun's out and I'm asleep when the sun is down?

But it turns out that if you look at health metrics, people that are strictly nocturnal do far worse on immune function, on metabolic function, et cetera, than people who are diurnal, who are awake during the daytime. And animals that are nocturnal, it's the opposite. And animals that are so-called crepuscular, which tend to be active at dawn and at dusk, this is a beautiful system, I won't go down that rabbit hole, but these are animals whose visual systems operate best.

They tend to be predators like mountain lions. They have optimized their waking times for the times when the animals they eat can't see well in those light conditions. But given the rod-cone ratios in their eyes, the mountain lion is picking off, it's like when you see special forces and they are looking through night vision goggles and they have a clear advantage, right?

They are seeing in the dark. That's basically what it's like to be a mountain lion as opposed to a bunny rabbit. - Would you say that a lot of these cycles evolved in the predator-prey relationships of the different, throughout the food chain? So it's basically all somehow has to do with survival in this complicated web of predators and prey?

- Almost certainly. There had to have been a time in which humans being awake and active at night as opposed to during the day led to higher levels of lethality. And probably particular in kids, you imagine kids running around in the dark and getting where there are a lot of animals that can see really well under those conditions and humans can't.

And this would be all pre-electricity. Even if you're carrying a torch, I mean the range of illumination on a torch is nothing compared to what a nighttime predator like a large cat or something can do. I mean, they basically, they can see everything they need to in order to eat us and not the other way around.

- So one fascinating thing you said is that blew my mind and we went right past it, which is the temperature is a really powerful, like if you were to think about the ways that different parts of the body, different systems in the body would communicate with each other, temperature would be a really good one.

And that just, I mean maybe it's obvious, but it kind of blew my mind just now that yeah, these systems are all distributed. - Right. - And they have to kind of, they're not actually sending signals, but they're coordinating. They need some sort of universal thing to look at in order to coordinate.

And temperature is a nice one to build around. And that way you could control the behavior of all these different systems by controlling the temperature. - Right. It's attractive to think of a mechanism where this master circadian clock secretes a peptide or something that goes and locks to receptors in all the cells and gets it just right.

But that leaves far too much room for variability, binding affinities, cells in a lot of parts of our body are at different stages of maturation. They're turning over liver cells and so forth. And for instance, we have a clock in our gut and in our liver, such that if we were just take out your liver and put it on a table and just look at the expression of these genes, it would be in a 24 hour oscillation on its own.

It's independent. But something has to entrain them and keep them all synchronized. And so it's not obvious that it would be temperature. Takahashi's great gift to biology was to show that all the stuff coming out of this master circadian clock at the end of the day, that's a weird statement, no pun intended, at the end of the day and the night, at the end of the story, it all boils down to making sure that the temperature of tissues oscillates in the same fashion.

- That's blowing my mind and thinking like what other mechanism could possibly exist to create that kind of oscillation. - You're Russian, it's cold in Russia for a lot of the year. The hibernation signal in certain animals is a remarkable signal. There are peptides secreted from this very same clock that in animals like ground squirrels or bears, they go into a kind of a torpor where everything, reproduction, metabolism, everything is reduced while they're in their cave.

They don't actually stay asleep all of winter, that's a myth. And they actually do these very dramatic and periodic arousals from hibernation where they just shake and shake and shake, it looks like a seizure and then they go back under into the torpor. That's from a peptide that's released.

But that's different because that's about shutting down the whole system. It's clear that having these very regular oscillations every 24 hours is essential for everything from metabolism to reproduction. - Is there an optimal temperature for sleep that I should mention, I think your latest episode, and people should go check out helixsleep.com/huberman to support Andrew.

- Thanks for the plug. (both laughing) I mean, the amazing thing about the stuff they create, and oh, and yes, you have a new podcast, that's amazing. And this past month he did a whole series on sleep, which people should definitely check out. There's some podcasts that come out that just make me wanna be a better human being by just the quality.

Three Blue One Brown, Grant Sanderson is like that for me. Just like, wow, this is, education is best. So Andrew symbolizes that, captures that brilliantly. So go support the sponsor so he doesn't stop doing the thing. So they, I think they have a cooling pad too. So I, Eight Sleep Mattress sponsors me.

They've been, they sent me a mattress and it's been, I've never, listen, I used to sleep on the floor. - Sleep where you fall. - Sleep where I fall, I don't give a shit. It doesn't really matter. So like I would have never bought a nice mattress 'cause it's like, why, I'm fine.

This is the floor, it's fine. But it was a game changer to be able to control temperature. Like for me, it's cooling. I don't know what the hell it is. - Well, you want the brain and nervous system and rest of the body needs to drop by about anywhere from two to three degrees in order to get into your deepest sleep and transition to sleep.

That's really gonna help. You don't wanna be cold that you're bothered and can't fall asleep. But that's why some people like it really cold in the room and under a warm blanket or with socks on for some people. That can be good because this temperature oscillation is such that as your temperature is dropping, that correlates with the, generally with the most sleepy phase of your circadian cycle.

So cool is better for falling and staying asleep and sleeping deeply. - And then I guess like that's what Eight Sleep showed. They have like an app is it warms back up to wake you up. The idea that I haven't actually used it. I'm like, this is stupid. People say it works, but I just keep it the same temperature throughout the night.

But warming it up, I guess wakes you up, which is fascinating. - Yeah, because the wake up signal is, it's interesting to think about it. It's not just correlated with an increase in body temperature. The increase in body temperature is triggering the release of cortisol from your adrenals. And that's the wake up signal.

- Do you think it's absolute temperatures we're talking about is just even relative, just even just the decrease? - Well, everyone's gonna have slightly different basal temperature. The idea that everybody should be 98.6. I mean, that's a myth. And there's a theories that body temperature overall has been dropping in the last 50 years or so.

I doubt that's true for somebody who is athletic like you and is young and healthy. But basically the coldest period of that 24 hour cycle is when you are going to be sleepiest. There's actually a period within that 24 hour cycle. It's a time point called your temperature minimum.

And your temperature minimum tends to be about two hours before your typical wake up time. I'm not talking about the wake up time in the middle of the night where you go use the bathroom or where you set an alarm to go catch a flight. I mean, if you were to just allow yourself to sleep without a clock for a few days, measure when you typically wake up, two hours before then is your temperature minimum.

And that temperature minimum turns out to be a very important landmark in your circadian cycle. Because it turns out that if you get bright light in your eyes in the hours immediately before your temperature minimum, so two to four hours or anytime within the two or four hour window before that temperature minimum, you are going to what's called delay your circadian clock.

The next day, that whole oscillation is going to move forward. It'll make you want to go to sleep later and wake up later. Whereas if you get bright light in your eyes in the hours after that temperature minimum, so let's say for me, typical wake up time is 6 a.m.

My temperature minimum is somewhere around 4 a.m. If I get bright light in my eyes, 5 a.m., 6 a.m., 7 a.m., it's going to advance that oscillation so that I'll want to go to bed earlier and wake up earlier the subsequent nights. So you might say, wait, but most nights I go to sleep and wake up at more or less the same time.

Why is that? And that's because the same thing is happening on both sides. You are both advancing your clock a little bit and assuming that you're looking at light in the evening, you're also delaying your clock a little bit. So you get kind of captured in between and then your rhythm more or less oscillates at the same period as we say, as the spin of the earth.

Unless you're like you where you're, I get text messages from you sometimes at odd hours. And if you're on the East Coast, then I know that you had to have been pulling basically an all nighter. - Yeah, yeah. That's the interesting point about the messiness of sleep. So most people seem to perform the best when they have like a regular sleep schedule.

I perhaps am the same, but I don't know that. And I tend to believe that you can also perform relatively optimally with chaos of sleep, of like a weird soup of like, power naps and all nighters and all of that. As long as you're like happy doing what you love.

And maybe you can tell me what you think about this. I tend to, for myself, try to minimize stress in life. So what I found for myself with diet, with sleep, is that if I obsess about it being perfect, then I'll actually stress quite a bit when it's not.

Like I'll feel shitty when I don't get enough sleep because I know I should be getting more sleep as opposed to the actual physiological effects of not getting enough sleep. I find if I just accept whatever the hell happens, happens and smile and just take it all in, like David Goggins style, like if it sucks, it's even better or what is it?

Jaco's like good or whatever he says. - Right, I think that several things that you said they're important, but I agree that one can have a dysregulated sleep schedule and still be a happy person and productive. In much of my life, I've pulled all nighters and slept weird schedules.

I think many people can probably relate to going to sleep, waking up four hours later, being up for an hour or two on your computer, then going back to sleep and getting amazing sleep the next day functioning. I think it's important that people have highlighted the importance of sleep and getting enough rest.

I do think it's gone too far and now I'm editorializing a little bit, but I think that we've created this anxiety about sleep that if we don't sleep enough, we're going to get dementia. If we don't get sleep, then the reproductive axis is going to completely crash. There's a lot of evidence to the contrary and as well, just based on personal experience and based on the fact that sure, it may be that a solid eight hours with no interruptions in there or nine or 10 could do great benefit, but you can do really well if you do what you say, which is you wake up, you don't want to start stressing about it, creating this meta stress about sleep.

Being happy is actually one of the most powerful things that you can do, not allowing yourself to go down that rabbit hole of stress for the following reason, a lot of our fatigue is not due just to the buildup of adenosine or time of day, the circadian thing we were talking about earlier.

An additional factor is that effort is related to the release of epinephrine, of adrenaline in our brain and body. At some point, those levels get so high that we get stressed mentally, we get stressed physically and we want to give up. There are good data published in Cell showing that that signal, the epinephrine signal is eventually accumulates and there's a quick point.

Dopamine, the molecule of pursuit and reward and feeling good, resets our ability to be in effort. In fact, a lot of people don't know this, but dopamine is actually what epinephrine is made from. If you look at the biochemical cascade, it starts with tyrosine, which is rich and found in red meats and things of that sort.

And tyrosine is eventually converted through things like L-DOPA into dopamine. Dopamine is made into epinephrine. So, I mean, this sounds kind of new agey, but happiness, joy and pleasure in what you're doing creates a chemical milieu that provides more of the chemicals that allow for effort. And there's nothing new agey about that.

It's in every biochemistry textbook. It's in every decent neuroscience textbook. They just don't talk about the happiness part. They just talk about the dopamine part. So I think that limiting your stress and at least recognizing, okay, if you're pulling an all nighter, you're somehow on messed up sleep, that there is going to be a point in that 24 hour cycle where your brain is not trustworthy, where your mental state is not worth placing too much weight on because you are near that temperature minimum.

And near that temperature minimum, which is correlates to that two hour, about two hours before you would normally wake up, the brain is hobbling along. And anything you feel or think at that time should not be given too much value. But if you can trick yourself into thinking that's the pleasure point, you afford yourself a huge advantage.

There's a study done by a colleague of mine at Stanford that showed that positive anticipation about the next day events actually is a powerful metric for creating quality sleep, even if the sleep is very reduced. And you'll love this one. And a lot of people might be critical of this, so I just want to make sure that, so this is work done out of Harvard Medical.

It was Bob Stigold's lab, and Emily Hoagland did this study that showed looking at performance on OCHEM scores. Okay, so organic chemistry at Harvard is pretty tough subject, highly motivated. A number of very good control groups in this study. What she showed was that consistency of total sleep duration was far more important for performance on these exams than total sleep duration itself.

So it's not that just getting more sleep allows you to perform better. Consistently getting about the same amount of sleep is better for performance, at least on OCHEM, than just getting more. - That's interesting. So that's referring to more that there should be a consistent habit versus the total amount.

- To me, the entirety of the picture of sleep is similar to nutrition in that it feels like there's so many variables involved, and it's so person-specific. So a lot of studies, I mean, this is the way of science, has to look and aggregate the effects on sleep. It doesn't focus on high performers, which are individuals, ultimately.

The question isn't, so it's a very important question, is what kind of diet fights obesity, reduces obesity? It's another question, what kind of diet allows David Goggins to be the best version of himself? So these high performers in different avenues. And the same thing with sleep. People that tell me that I should get eight hours of sleep, it's like, I mean, I get it, and they may be right, but they may be very wrong.

- There's no evidence that eight is better than six, that you could very well do better on six than on eight. There are a few other things that turn out to be strong parameters for success in this domain. For instance, your entire life, waking or asleep, is broken up into these 90-minute ultradian cycles.

If you look at ability to attend or do math problems or do anything, drive, performance tends to ramp up slowly within a 90-minute cycle, peak, and then come down at the end of that 90-minute cycle. And in sleep, we go through these stage one, two, three, four, REM, et cetera, we'll talk more about that if you like, those on 90-minute ultradian cycles as well.

Ending your sleep after a 90-minute cycle, near the end of a 90-minute cycle, say at the end of six hours, in many cases is better for you than sleeping an additional hour, seven hours, and waking up in the middle of an ultradian cycle. And there are a few apps that can measure this based on body movements and things like that, that have your alarm go off at the end of an ultradian cycle.

And if you wake up in the middle of an ultradian cycle, sometimes, not always, you can be very groggy for a long period of time. I certainly do better on six hours than I do on seven. I happen to like an eight-hour sleep, it feels great, but I haven't slept an entire eight hours without waking up in the middle of the night at some point in, I don't know, forever, I can't remember.

It's probably some point in infancy, but, and I function well during the day. I think that that's a big, that's an important parameter, is how do you feel during the day? Almost everybody experiences some sort of dip in energy in the late afternoon, or what would correlate to their temperature peak.

And that's a good time of day to get either a 90-minute or less nap, or if you're not a napper, or you can't nap, feet elevated has been shown to be good for clear out of some of this, the glymphatic system is this kind of like sewer system of the brain that you can clear stuff out.

So legs elevated, or one thing that I'm a big proponent of, and that my lab has been studying, is what I now call NSDR, non-sleep deep rest. And this is just lying down. There are some scripts that we're going to put out there soon as a free resource. There's some hypnosis scripts that my colleague David Spiegel has put out there as a free resource.

But non-sleep deep rest is allowing your system to drop into states of real calm that allow you to get better at falling asleep later. And they can be very restorative for cognitive and motor function. There's at least one study out of Denmark that shows that the basal ganglia, which is an area of the brain that's involved in motor planning and action, one of these 20-minute non-sleep deep rest protocols resets levels of neuromodulators like dopamine in the basal ganglia to the same levels that they were right after a long night's sleep.

So I also respectfully or semi-respectfully disagree with the idea that you can't recover lost sleep. What does that mean? I mean, there's no IRS for sleep. So what does it mean to be in debt for sleep? If you're falling asleep during the day and you're sleepy, like you're falling asleep, that's a good sign of insomnia.

It means you're not sleeping enough at night. If you're fatigued during the day, but you're not falling asleep, so you're just exhausted, but you're not finding yourself falling asleep in meetings and in conversation, then chances are you're fatiguing your system through something else, like a long run in the middle of the night in Boston or whatever it is that you're up to lately at 3 a.m.

- Yes, there is a magic to the nap. And maybe you could speak to the, 'cause you mentioned these protocols that don't necessarily, so they're non-sleep. But to me, the nap, one or two a day, can almost, irrespective of how much sleep I get the night before, have a fundamental change in my mood and my performance.

- For the better? - For the better, for the better. - Yeah, likewise. - So I do tend to kind of experiment with durations. It's consistently surprising to me how a nap of 10 minutes, I don't know, maybe you could speak to the perfect duration of a nap, but I find that it's like magic that a short nap does as much good and often better than a longer one for me, for me.

Subjective experience. - What would be a longer one? Longer than 90 minutes? - No, no, like 90 minutes, but longer than 90, like two hours. - Yeah, that's dropping you, starting to drop you into REM sleep. And even if it's a tiny amount of REM sleep, people can come out of those naps kind of disoriented.

I mean, remember in sleep, space and time are totally uncoupled. And so that's an odd state to reenter the world in if you're not gonna stay there for a while, like for a good night's sleep. I think a 20 minute nap is pretty fantastic. - Would you say that's the, if you were to recommend to the general, it's very weird to recommend anything to the general populace because obviously it's very person specific, but what's a good one will you say to friends?

Is 20 minutes a good time? - 20 or 30 minutes. 20 or 30 minutes 'cause you're going, unless you're sleep deprived, you're going to stay out of REM sleep, rapid eye movement sleep. If you're sleep deprived, you'll drop right into it. If you've ever traveled and you're really jet lagged, you go to the hotel, you lay down for one second, all of a sudden you're just like, you're in a psychedelic dream, which can be pretty great too.

But I think that 20, 30 minutes, and if you can't sleep, some people have trouble napping, then learning to relax the body as much as possible, like trying to remove all expression from your face, completely letting your body kind of float. If people have a hard time relaxing when they're awake, there's some terrific clinically and research tested hypnosis protocols that we could provide links to that are cost-free and that teach you how to just completely release the alertness button and you just start drifting.

Now, the problem is if you don't have an alarm or something to go off, the other day I did one and I'm almost embarrassed to say this, but there's a component of it where you actually are supposed to let your hand float up because it's a hypnosis script. So they, it's my colleague, David Spiegel, in the script, he says, let your hand float up.

I woke up an hour later and my hand was still floating. - Wow, that's awesome. - And I was completely relaxed. So hypnosis is just a matter of going deep relaxation, narrowing of context, and it's all self-imposed. A lot of people think that hypnosis is like the stage thing with the pendant and the chicken, people fucking like chickens, but real hypnosis is self-hypnosis.

You're learning to, it involves some shifts in the way that you, the hypnotic induction involves looking up, closing your eyes, slowly deep breath, and then imagine yourself floating. And people vary on a scale of about one to four, four being the most easily hypnotized. There are a few people who it's very hard for them to allow themselves to go into these states, but for most people, they just, they're gone.

And it's nice if you can have access to those states, because when you come out of it, you feel amazing. You feel like you slept the whole night, at least most people report that. - So refresh, alert. - Ready to go. I mean, basically you're ready. Yeah, I know you have this interesting challenge coming up, and I'm curious what you're going to do to reset in the hours that the frequency of running is every four hours.

It's not going to allow you to get any more than a couple hours sleep in between. - A couple hours, so we should tell to people, I'd be curious to get your thoughts and advice on it. I'm on March 5th, running 48 miles with Mr. David Goggins. So four miles every four hours, and people should join us.

That madman is going to be live on Instagram, starting at 8 p.m. Pacific on March 5th. So-- - You're gonna join him in person? - In person. - Undisclosed location. - Undisclosed location. And I was trying to clarify, like, okay, so we're gonna, like, there'll be like friendly people around or something.

No, it's just me and him. - Friendly people. - I don't know, like, I just feel it's very difficult to be with David alone in a room. - I imagine his, I mean, I've done some work with David. His energy is infectious. - Yeah. - That's an intense schedule, and the periodicity of those four hour, every four hours, four miles, means that there's no chance of catching an extended block of sleep.

- So it's about three hours that you have non-exercising every time. And of course, it takes time to try to fall asleep, and there's an intensity to the whole thing. I mean, it's probably impossible to get anything more than two hours of sleep if you wanted to. So the optimal thing is probably, from the sound of it, I'd be curious to see what you think, but like it's getting a few 90 minute naps.

- Yeah, well, I thought about this a bit before we met up today. So I think there are two general approaches that could work, neither one necessarily better than the other. One would be just to hammer through the whole thing, just to get your level of alertness and adrenaline ramped up so that you don't expect yourself to sleep.

There are certain advantages there. One is a subjective kind of emotional advantages, which is if you can't sleep, you're not going to be stressed about that. And if you do fall asleep, it's a bonus, provided you wake up and you don't look up and you realize David's been out running for half an hour and you're behind, right?

But chances are that's not the way it'll go. You'll set an alarm. So that's one approach. And I grabbed that from, you know, I've a couple of friends who were in the SEAL teams, and they'll say that, you know, during BUD/S there's this infamous hell week, and there's this five day, excuse me, definitely five days of no sleep.

Although there is a component where they offer a nap at one particular point. And a lot of people will say that it's worse to go down for that nap and then be woken up 20 minutes later than to just stay up. So that's one option. Let's call it the full blitz hammer through option.

And if you happen to fall asleep, you do. - Bonus, yeah. - It's a bonus. The other one would be to really anchor in these ultradian cycles. So coming back from a run, unless you're thoroughly exhausted, you're probably going to have a few minutes where you're going to want to stay awake.

It's going to be hard to just immediately fall asleep. And getting as much sleep as you can in the intervening periods, provided that you guys aren't posting constantly or doing something else. You also, there's a question of whether or not you want to nourish, whether or not you want to eat or not in that time.

Anytime we put food in our gut, I don't care if it's meat or oatmeal or broccoli or cardboard, you're drawing blood into the gut. And so you are going to divert some energy towards digestion and it's going to make you sleepy. There's a reason why the rest and digest, the parasympathetic nervous system is called that.

So you could decide that you were only going to sleep in certain, in between certain blocks. That would be another way to think about this. - That, 'cause I did this last year. I ran very slow. Some of it was walking. I was listening to audio books. And one of the biggest mistakes I did is to overeat during that time.

It was, it made the experience very unpleasant. So I have been considering basically eating almost nothing throughout the day. - Being fasted will increase alertness because high levels of epinephrine in your system from fasting. You just think about fasting or being thirsty before you get exhausted. People always think, if I don't eat, I'm going to be tired.

No, the energy that you derive from food is going to be used from glycogen. And after a long storage and conversion process. So the food that you eat is going to consume energy to digest. And so a lot of people feel better fasted. And presumably throughout history, people have fasted for long periods of time and had to stay up for two or three days.

And God forbid, if a family member is sick, you can stay awake in the hospital without any trouble. So that alertness system, and it's all mental. Actually, and then there's a third. So you could try and sleep or take care in between. - Yes. - Yeah, and then there's a third approach.

- Uh-oh, yeah. - But I didn't come up with it, but David did. So I actually texted him earlier because I had a feeling that I heard that you were going to do this challenge. So I asked David. So these are David Goggins words, not mine. - Okay. - One.

Being organized is super important. Two, you want to waste as little time as possible. Three, you need to eat, sleep, and rehab in as little time as possible so you can sleep as much as possible. Oh, interesting. By the way, this is the first time I'm reading this. - Yeah.

- Four, meal prep and gear prep, et cetera, are very important. That's consistent with everything I know about military. They don't leave too much to chance. Five, again, these are David's words. All that said, he's fucked on most all that because he'll be interviewing me before or after. I will also be interviewing him.

- Oh, shit. - Five, long story short, the only thing that might help is a very special pill. Ooh, this is interesting. They're called SIU pills. Hard to get, but I believe he can get them. SIU stands for suck it up. Tell him to grab his balls. He will find those pills there.

- That's number six, all right. - And then the last one, stay hard, brother. - Stay hard, brother. - Amen. That was one of the other things that I think makes this challenging is that I'll be doing a podcast throughout. So first of all, I'll do a long one before and after, but also I'll have to come up with things to talk to him about.

So it's a different thing to do something privately and then publicly. I know it doesn't seem that way, but one of the hardest, the hardest thing I had to do last time was to turn on the camera and talk to the camera. 'Cause last time I did it, I recorded every single time I did a leg, I recorded something I'm grateful for.

It's just kind of unrelated. I'm not a fan of talking about how I'm feeling or how the run is going. I wanna do something totally unrelated to the run with the run as the background, sort of something I'm grateful for, just any kind of interesting discussion. - Gratitude, I mean, I hate the word hack, like, oh, it's a dopamine hack or it's a serotonin.

I don't like the word hack because A, it's disrespectful to hackers who do a real thing. And B, a hack implies that it's some sort of trick that you're kind of gaming the system. You know, what works is mechanism, right? Biological mechanisms were designed to work and they were selected for to work under variable conditions.

And as you know, and I know, and we have great appreciation for the fact that the nervous system was designed to be an adaptive machine so that you don't have to sleep eight hours every night. You can do this thing. And things like gratitude allow you to tap into chemical resources.

And that's not a hack. The fact that being grateful for something external to the event happens to release serotonin and have a certain soothing effect or dopamine and give you more epinephrine and let you go further, that's not a hack. That's actually what allowed the human machine to evolve to the point that it is now.

Every time, you know, an inventor eventually created something that worked and felt great about it, you can imagine that the first, you know, air flight felt pretty awesome and motivated those people to go on and do more. They didn't just go on, you know, yawning, go have a beer.

So being able to access the genuine internal states of gratitude and reward works. You can't trick the system. You can't pretend that you're grateful for something. But if you can identify or attach yourself to some larger goal or something that's deeply gratifying to you, or place it in service to a relative that passed away that you care a lot about, that's not a hack.

That's accessing the deepest components of your nervous system. And to steal your kind of lingo, you know, there's real beauty there, right? (both laughing) - Yeah, but for an introvert like myself, and I think David, I don't know if he's an introvert, but like he's not, despite the fact that he has written a great book and he communicates, he puts himself out there, he's not really a fan of communication.

He's not, I don't know if he's energized by speaking his mind. - I don't know well enough to know. I mean, we've done a little bit of work together and we're in communication now and again. He's obviously super impressive. I don't know. It seems like he's a pretty private guy.

So I don't have access to that. - So for me, I'll just speak to myself, and I think David is the same, but I'll speak to myself that it was a hugely draining thing not to experience the gratitude, experiencing the gratitude, just like you're saying is really energizing. And it's a powerful thing.

It can lift up your mood, but to turn on the camera and have to use words, which is very difficult to do, to explain like what you're feeling and do it in a way that you know a bunch of people will be watching is really draining. And one of the things I'm concerned about that in this whole process, how do I keep my mind sharp while also keeping the physical performance sharp?

And that's a little bit scary because talking to David, like actually intellectually sharp, like thinking, being charismatic as much as I can be and like being still maintaining a sense of humor too, 'cause I become with sleep deprivation, with exhaustion, you start being- - The Russian bear comes out.

- You start being such a, like I become a David Goggins essentially like- - Oh, it makes you irritable. Sleep deprivation makes us irritable. - Yeah. - It's clear so that in the early part of the night, we get a higher percentage of those old tradian cycles are occupied by slow wave sleep, sometimes just called non-REM sleep.

And those early night sleep bouts are great for muscular repair and for certain forms of learning, but REM sleep, the rapid eye movement sleep, which it starts to accumulate and occupy more of those 90 minute old tradian cycles toward the late part of a sleep bout. So typically toward morning, but after you've been asleep a while, that's when you do the emotional processing.

That's when we recover the ability to feel refreshed and not irritated by things. And if you deprive people of REM sleep, they become selectively bad at uncoupling the emotion from things that happened in the previous days. So the little things start to seem like big things. I always know I'm REM sleep deprived when I'm irritable.

And when I look at like the word the, and it doesn't look like it's spelled right, and I'm kind of off about it. Like something's off. And we actually are becoming slightly psychotic when we're REM sleep deprived. You're not gonna get a lot of REM sleep in this thing, except as you fatigue more, if you do fall asleep, you're gonna drop more and more into REM so that those 90 minute cycles, you won't have to go through stage one, stage two, stage three, and then REM, you're just gonna drop right into REM.

So you can count on your system to compensate for you. But I think that just the knowledge that you tend to get irritable as the time goes on, just that third personing of yourself, that awareness, the observer, that can be very beneficial because there may be bouts during this event when you just should probably say nothing.

And maybe you just, I don't know, smile and record or not smile or do whatever it is, because you're gonna be conserving energy. If it feels like a grind, that's epinephrine being released. That's epinephrine that you could devote to the physical effort. But humor is an amazing anecdote for this because it resets that, it's that dopamine release that gives us that fresh perspective.

And it's a real chemical thing. It's not a hack, it's not a trick, it's not a visualization, it's biology in action. - Well, but I think the act of interviewing, of conversation in these processes, even if you don't wanna do it, the right thing to do, even when you're feeling irritable, is to do the third person view and be able to express with words that you're feeling irritable.

Like express what you're going through, use words, which I hate doing. I honestly, I think my ultimate thing would be just to never say a single word to David Goggins and just go through hell. It doesn't matter what we do, but to do it quietly, to also express it, that's my ultimate hell.

- And he's definitely gonna be, if I know David at all, he's going to try and find your buttons. Like he's gonna, I mean, he, even though he knows he can complete this, and I believe that he trusts that you can complete it too, I believe you can, you will complete it.

You know you will complete it, right? There's no question about that. But he's not gonna make it easier for you, he's gonna make it harder. - Well, I'm afraid, so I'm like, you know, it's very difficult for me. So 48 miles is not easy. I have not been training that much, so I'm not ramping up, but it's not like going to kill me.

We'll see what happens. Of course, for him, he might almost get bored because I think the 48 miles for him is easy. I think-- - I don't know that ever gets easy. I have a friend, Casey Cordial, who works with David. He does some physical rehab type stuff with him.

And he took Casey on a 50 miler, and Casey said it's like 16 miles into it, he was just like, he'd hit his wall. But he found it, they find it to get, you know, you find that portal. There is one thing I want to mention. There's some very good physiology that can perhaps support the actual running effort part.

These are very new data. And we have a study going on with David Spiegel at Stanford looking at how different patterns of breathing can affect heart rate variability. Heart rate variability is good. There's this interesting mechanism that I think most people might not realize, but that medical students learn that your breathing and your heart rate and your brain are in this really remarkable interplay.

It goes like this. When you inhale, this isn't breath work, we're not going to do breath work. But when you inhale, the diaphragm moves down. The heart gets a little bigger 'cause there's a little more space in the thoracic cavity. And as a consequence, blood flows a little bit more slowly through that larger volume.

And there's a category of neurons, the sinonatrial node that sees that, that recognizes that slower rate through that larger volume. It sends a signal to the brainstem and the brainstem sends a signal back to the heart to speed the heart up. So every time you inhale, you're speeding the heart up.

When you exhale, the diaphragm moves up, the heart gets a little smaller, the volume is smaller, blood flows more quickly through the heart, signal sent up to the brain, and the brain sends a signal back to slow the heart down. This is the basis of heart rate variability. So at any point, if you feel like your heart is racing and you feel like you're working too hard per unit of effort, focus on making your exhales longer or more intense than your inhales.

If ever you feel like you're truly flagging, you do not have the energy to get up, it's like, okay, it's time to go and you're exhausted, you want to draw more oxygen into the system, get your heart rate going faster. Now, some people, when they hear this probably thinking, well, this is really obvious, but there's so much out there about breath work and how to breathe and all this stuff, but no one talks about how to do it in real time while you're exerting effort.

- So this is something like almost like second by second, you can adjust things that just in real time based on how you're feeling, but it's based on the heart rate. - That's right. - The variance of the heart rate. - That's right. So one thing that could be very efficient and we're doing some work with athletes now, so these are unpublished data, but if you, while you're running, if you want to get into a nice cadence of heart rate variability, do double inhales while you're running.

What this will do is that when you do the double inhale has the effect of reopening the alveoli of the lungs, your lungs are filled with tons of little sacks, when you, they tend to collapse as you fatigue, when you, and carbon dioxide builds up in the bloodstream. And that's when we start getting stressed.

If you've ever been sprinting, you start getting beat and you're going as hard as you can, what you really need to do is double inhale and reinflate these sacks in the lungs and then offload a lot of carbon dioxide. So when you're at a steady cadence and you're feeling good, double inhale, exhale, double inhale, exhale is a terrific way to breathe while you're in ongoing effort.

- By the way, any recommendations or differences in nose or mouth breathing? - So nasal breathing, there's a lot of excitement now, obviously about nasal breathing 'cause of James Nestor's book, "Breath." There was also, if people are going to know about that book, that I do feel like out of respect for my colleagues, there was a book by Sandra Kahn and Paul Ehrlich at Stanford, both professors at Stanford, with a forward by Jared Diamond and Robert Sapolsky.

So some heavy hitters in this book. And the book is called "Jaws, A Hidden Epidemic." And it's all about how nasal breathing is better for us, especially kids, than being mouth breathers under most conditions for sake of improving immunity. It turns out there's a microbiome in the nose, like all sorts of good stuff about nasal breathing preferentially.

But when we exercise, you can do pure nasal breathing, but the problem is once you get up to kind of third and fourth and fifth gear effort, you can't nasal breathe and be at maximum capacity unless you've been training it for a very long time. So I would say double inhale through the nose, offload through the mouth.

So double inhale, exhale while you're in steady effort. And then if you really feel like you need to gas it and you're pushing, the data show that then just use whatever's there, right? Just go into kind of default mode because bringing too much concentration to something is also going to spend epinephrine.

The goal is to get into that, I don't like the word, but the flow state where you're not thinking too much, you're just in exertion. So these are things that can help in the transitions, but I don't think there's any secret breathing technique. Anyone who's been in the SEAL teams will kind of, they'll tell you like, there's no breathing technique, right?

There's tools that you can look to from time to time. And these double inhale exhales can be great for setting heart rate variability very quickly and getting into a steady cadence while you're exercising. But if there's a sprint, like if suddenly you guys are sprinting, ditch the double inhale, exhale and just sprint.

- One thing that you mentioned, he's probably gonna push my buttons. It's a good place to ask a question about anger. So I'll probably get pissed off at him at some point, I'm guessing. And do you have thoughts from a scientific perspective or also just the personal philosophical perspective about the role of anger and all of this in managing alertness, performance?

- I think about this a lot because there's so much out there about how important it is to do things from a place of love. - I tweet about it all the time. - And I think, and love is powerful, right? It is interesting that autonomic arousal, alertness, let's just make use simple language, alertness physiologically looks identical for love and excitement as it does for anger and frustration and wanting to defeat your opponent or whoever that opponent happens to be.

They're identical, except that the love component does tend to be associated with the release of neurochemicals of the serotonin and dopamine type that do have this replenishment component. I don't think one wants to be in constant anger and friction, but I mean, I'll come clean a bit. There've been portions of my career where some of my best work, my extra two hours, my ability to nail a really hard deadline or problem has come from not wanting to get out competed or from wanting to prove something.

These days, I'm not oriented from that place toward my work quite as often, but I think we should be really honest. Anger is powerful, provided it's channeled. It's very, very powerful and it can give you a ton of fuel and gas to push when otherwise you'd tap. - Yeah, Joe Rogan has, aside from being a fan of his, has been an inspiration to sort of be, to have a kind of loving view on the world in the way he approached the world, to me.

So I've tended to want to approach the world that way, but in the same way, David Goggins has been an inspiration to like, yeah, be angry at stuff and use it as fuel. Like he almost conjures up artificial demons in his mind just so he can fight them. But at the same time, I tried that 'cause I did a challenge in the summer of, well, for 30 days, I was doing a lot of pushups and it was, over time, it was counterproductive for me.

I found that it was easier to just, like the rollercoaster that the emotional, like being angry at stuff takes you, can also be exhausting. - Oh, absolutely. - And it can take you down, like the ups of it are good, but the downs are bad. And what I found is better to get, to use it as a boost every once in a while, but mostly to get lost in the, you're talking about the breath work, like getting lost in the ritual of it, like the beat, like that, as opposed to going on the big rollercoasters of emotion.

- Yeah, this brings us into the realm of neuroendocrinology. There's a fascinating relationship between the hormone system and the nervous system. And hormones work in general on slower timescales. The definition of a hormone is something, is a chemical released at one location in the body, goes and acts at multiple locations far away within the body.

Pheromone would be between two bodies. Neurochemicals like dopamine and serotonin tend to work a little more quickly. There are hormones like adrenaline and cortisol that can work very fast, but here I'm referring mainly to testosterone, prolactin, prolactin tends to be in men and women, tends to make people kind of lazy and want to take care of young.

It tends to throw down body fat so we can stay up late. It's secreted in response to having children. These are all in humans and in animals. There's a very interesting relationship between testosterone and dopamine that speaks directly to what we're talking about now. So dopamine and testosterone are closely related in the pituitary system.

And obviously testosterone comes from the adrenals and from the testes. But the major effect of testosterone is to make effort feel good. That's what testosterone does. It has other effects too, right? Reproductive effects, androgenizing parts of the body, et cetera, but it makes effort feel good. The testosterone molecule is synthesized from cholesterol.

Cholesterol can either be made into cortisol, a stress hormone, or testosterone, but not both. So you have a limited amount of cholesterol and it gets diverted towards stress or this pathway where effort feels good. That's the pathway you want to get into. The anger pathway, if we were to just kind of play a mind experiment here, the anger eventually is going to divert more of that cholesterol molecule to cortisol and stress, and you will be slowly depleting testosterone.

Now going into this, you'll have plenty of testosterone, but after a couple of days, there've been very interesting studies showing that testosterone doesn't necessarily drop with sleep deprivation. That's a bit of a myth. You need it to replenish, you need sleep to replenish testosterone eventually. But the real question is, are you enjoying what you're doing?

And here that the work was, some of the major work on this was done by Duncan French, who runs the UFC Training Center. He did his PhD at Yukon stores, did a really beautiful PhD thesis looking at the relationship between stress hormones, testosterone, and dopamine. Really interesting work. And the takeaway from all of this is, if you can just convince yourself, or ideally, if you can just enjoy yourself, you are going to maintain or maybe even increase testosterone stores, which will make effort feel good.

And to me, aside from neuroplasticity, where everything becomes automatic after this experience, to me, that's the Holy grail. When effort feels good, life just gets way better. And we're not talking about achieving the reward. I'm not talking about the end of this thing. I'm talking about the process of it feeling really good.

- Yeah, there is a magic to, I don't know if you can comment on this, but I find myself being able to, if I just say I'm feeling good, like this old hack of smiling while you're running. If I just tell myself I'm feeling really good right now, no matter how I'm actually feeling, I'll start feeling way better.

And the whole thing, there's a cascading effect that allows me to maximize the effort. It's quite fascinating. It's weird. - Hormones are powerful. The relationship between thoughts and hormones and these physiological things is enormous. I had a colleague that a few years ago, he was dying of pancreatic cancer.

And I was interviewing him just 'cause he's an important figure in our community. And I was a friend. And there was one day where he told me, he said, "I don't want to make it past the new year." And it was crushing for me to hear. And I knew that he had been on some androgen therapy for a whole set of other things.

And I said, "Have you taken your androgen cream?" And he was like, "No, I haven't done it. Go get it for me." I have this on film. He takes it, he puts the androgen cream on. I'm not suggesting people take androgens, by the way. 10 minutes later, he says, "You know what?

I think I want to live into the new year. And I'm going to write 12 letters of recommendation." He went to MIT, by the way. He said, "I'm going to write 12 letters of recommendation." And he did. And so there's something about these molecules that in an ancient way, in all organisms, all mammals, as far as we know, are linked to the will to live.

They're linked to effort and making effort feel good, which has been fundamental to the evolution of our species. I always say, people think that the opposite of testosterone is estrogen, but it's not. The opposite of testosterone is prolactin, which makes us feel quiescent and not in pursuit of things, et cetera.

Testosterone makes effort feel good. Estrogen makes emotions feel okay. And they are in mixed amounts. People, as I say, have all chromosomal backgrounds. - Yeah. - Yeah. - I mean, you also mentioned fasting potentially through this two-day thing. It'd be cool to get your thoughts about fasting in general.

Do you think, on a personal level and at a higher sort of level of studies that you're aware of and physiology and so on, what do you think about intermittent fasting of like not eating for 16 hours and then having an eight-hour window or something I've been doing a lot recently, which is eating only once a day.

So that's 24-hour fast, I guess, one meal a day. Or something I've been thinking about doing, haven't done yet, of doing like 72 hours. And some people do like five-day fasts in general. So this would be, for this particular run, would be a 48-hour fast if I don't eat at all.

What do you think about that for performance, for mood, for all those kinds of things? - I can speak a little bit to the science and a little bit of my own experience and then some anecdotes of people that have done very hard, very long-duration things and what they've told me.

So I just want to make sure I'm separating those out so people know my sourcing. I think, now, none of this is about the actual long-term nutritional benefits of one thing or the other. But if you look at the science on intermittent fasting, it's pretty remarkable. Before I was at Stanford, my lab was in San Diego.

One of my colleagues was Sachin Panda at the Salk, is phenomenal biologist and researcher. Wrote a book called "The Circadian Code." It's very, very good. And kind of popularized intermittent fasting, although there were others that had talked about this before, Ori Hoffmechler talked about the warrior diet. People probably might not know who Ori is, but he's sort of the originator of this business of intermittent fasting, eating once a day or limited.

Anyway, Sachin has published papers, peer-reviewed papers in very good journals like "Cell" and elsewhere, showing that limiting the consumption of calories to eight, four, six, or eight, or even 10 hours of every 24-hour cycle, and keeping that more or less correlated with the light, with when the sun is out, leads to less liver disease, improved metabolic markers, less body fat, et cetera.

In the mouse studies, they even gave the mice the choice to eat whatever they wanted, as much as they wanted, as long as they restricted it to a certain period of within the 24-hour cycle, they did great. They maintained a healthy weight or even lost weight. When they took the same amount of food and they stretched it out across the entire 24-hour cycle, so this is eating every hour or two hours, the animals got fat and sick.

So it's pretty remarkable data. How much of that translates to humans isn't clear, but one thing that's really clear with humans is adherence. Right, we could talk a lot about nutrition and some of the problems with the studies on nutrition is that what people will do in a laboratory is often hard to do in the real world.

Low-carbohydrate diets, just they tend, because they tend to focus on foods that have high amino acid content, like meats, generally people are less hungry on those than they are on calorie-matched diets of fruits and vegetables and carbohydrates, because when the insulin goes up, you get hungry and you want to eat more.

So this is not a push for carnivore or a push against one thing or the other, it's just there are a lot of factors. But we know for sure that when you're fasted or when you have low amounts of carbohydrate in your system, complex carbohydrate, your alertness is going to go up.

Fast increases alertness and epinephrine for the sole purpose of getting you to go out and find food. Can you imagine if our ancestors got hungry and they were like, "Oh, I'm too tired to go find food," we wouldn't be here. It'd be like robots or some, one of your alien buddies will be like running the planet.

So I think that if you want to be alert, fasting or keeping complex carbohydrates to a minimum is very valuable. If you want to sleep and you want to be sleepy, ingesting foods that have a lot of tryptophan, which is the precursor to serotonin, so complex carbohydrates like rice and grains, turkey, white meats, those things do create a sense of sleepiness.

However, there is a caveat, and this is one problem with the once a meal, once a day meal, is that anytime you have a lot of food in the gut, you're increasing sleepiness because you're diverting blood to the gut. It's going to trigger the vagus to signal to the brain to shut down your system and utilize those nutrients, digest and utilize those nutrients.

So I've done the once a day eating thing. The problem is I eat so much in that meal that I'm exhausted. And so it doesn't always lend itself well to the schedule. But so in a six or eight hour eating block for me is a little bit better. I do eat carbohydrates.

I'm probably one of the few people left on the West Coast that actually consumes carbohydrates and will say that out loud. - I don't know people who eat carbs anymore. That's weird. - They don't. - Where do you even find carbs these days? - I like oatmeal. I like rice.

The other time is if people are doing very high intensity weight train, they need to replenish glycogen. - On the alertness side, I do feel like it's probably person dependent. For me, alertness, being alert makes my life better in a lot of ways, more than just the alertness itself.

Like for example, one of the things I discovered with fasting is that when I was training twice a day in jiu-jitsu, for example, and competing and so on, I performed way better at things that you traditionally would say you need carbs for, which is explosive movements and all that.

I don't know if I actually perform better in terms of like the force of the explosion, the explosiveness. What I do know is the alertness resulted in me doing the technique more precisely. That's the dopamine and epinephrine system in action. There are some other just purely physical aspects to one diet versus the other that can be complicated.

If you're ingesting carbohydrates, complex carbohydrates, you're going to replenish glycogen, which is great, but they also tend to be bulky and fibrous. And I've never rolled jiu-jitsu, but running when you have a lot of bulky, fibrous food in your gut or in your intestine, it can be a barrier.

It can be uncomfortable. And so some people do really well on low carbohydrate, meat-rich diets because they're just not as bloated. They're not carrying as much water and other stuff. Carbohydrate carries a lot of water molecules with it. So there are aspects to being able to train and being really explosive 'cause you feel light.

One anecdote that really, again, I'm not encouraging any one particular kind of diet, but I have a friend who is in the SEAL teams. I happen to know a number of people in that community. And he told me that he did this very long fast. It was a fast that I think you get to eat a little bit of soup or broth, and there's like a bar or something, but it's like a nine-day thing.

And he's a very strong athlete. And he said that on day six or seven, he was running up some hills or something while he was on deployment, and he felt amazing. He had kind of hit this other level. He was somebody who had boxed in the Naval Academy. He was somebody who knows a new high output.

And he felt like he discovered the 13th floor, that there was another floor to this performance space that he hadn't experienced except while he had fasted. And he said that that was a remarkable clarity of mind, energy, it's a little bit of what you described. He described a kind of suppleness and explosiveness.

So there's probably something there. - On which day? - At once he was in the fifth or sixth day of the fast. - See, this is the thing is I've never been there on the second, third, fourth, fifth day, that kind of thing. But when I just don't eat for 20 hours, many times through my training, the clarity, it's like you feel like everyone is moving super slowly, and you're able to like dominate people you weren't able to before.

It's like-- - Well, you might have slipped into or switched over rather into full ketosis. And ketogenic diets done properly can be great for people. The problem is if you do it wrong, you can really mess it. I tried it once and I basically got psoriasis. I thought my scalp was gonna fall off.

I was like sloughing off all this. And then I stopped and I was taking the liquid ketones. And then all of a sudden I felt better again. But I was told that I just did it wrong. That's so I think there's a right way and a wrong way and you have to get it right.

- Definitely, and so I've experimented quite a bit with keto to see how my body feels and doing it the right way and following all the instructions that there's definitely a huge difference. For example, one of the things I discovered, everyone know who said this, but I tried this recently over the past year is I started drinking, when I don't feel great, if I'm fasting, bone broth, chicken bone broth.

And for some reason, like magically, it could be, this is the other thing, the mind, I don't know, but it makes me feel really good. - Well, it could be the salt. So I mean, neurons, the action potential neurons, as you know, is sodium is rushing into the cell.

You need enough extracellular sodium in order for your brain and nervous system to function. And so salt, I mean, unless people have hypertension, salt is great. There was an article in Science Magazine about a decade ago about how salt had been demonized. And unless people have hypertension, provide you drink enough water, salt is great.

You need sodium, magnesium, and potassium to function and for your nerve cells to work. I mean, people who over drink water and don't consume enough electrolyte die. Now, hydration is really important. I know David's really into hydration. He's mentioned that a few times. I mean, hydrating properly is key.

And so you definitely want to make sure that you're drinking enough water and getting enough electrolytes. We should have actually talked about that at the beginning because that's going to keep your nervous system functioning well. And a lot of people, they'll get shaky or jittery. And when they're fasting and they'll think they need sugar.

And if they just put some salt in some water, they feel fine. - And like the other stuff, potassium, magnesium, whatever the other electrolytes are, but yeah. - Yeah, those three. So I mean, salt, yeah. Magnesium's good before sleep. Salt, I mean, this is a vast space. And we're kind of talking about the overlap between neurochemicals, hormones, and nutrition.

And it's a fascinating space. And it's one that the academic community has gems within the textbooks. It hasn't really made it into the public sphere yet. And I think that's because people get so caught up in the, you know, being, are you vegan or are you carnivore? And there's a vast space in between too that people can explore.

Like I'm not a competitive athlete, so I eat meat and I also eat vegetables and I eat fruits. And it's just about timing them. But I tend to eat carbohydrates when I want to be sleepy. I eat them at night. And everyone said, that's the worst thing. You can't do that.

You sleep great after eating a big bowl of pasta, I'll tell you. - And by the way, I should give you a big thank you for connecting me with Belcampo Farms. They sent me some meat, I think because of you. (laughing) And it's delicious. So I really appreciate that.

I mean, it also connected me with this whole world of people who are doing farming in this ethical way and like really love the whole process. And like, and as from a both like a human level, but also scientific level and the result is, it's like ethical, but also it's delicious.

And it makes you think about your diet in a whole new kind of way. - Yeah, I've known, I don't have any commercial relationship to Belcampo, so I can be very clear. I've known Anya Fernald, who is the founder and CEO of Belcampo. I've known her since the ninth grade.

It is true that her parents are faculty members at Stanford. They're colleagues of mine, but she's just a serious academic of nutrition, but also of sustainable agriculture, of all sorts of things. And also the meat just, it's awesome. It tastes really good. And no, I'm not getting paid to say that.

No, they're not sponsoring my podcast. It's just, I feel like if you're gonna eat animals, if that's in your framework and you're gonna eat animals, knowing that the animals were raised as happy as could be until time of slaughter is at least important to me. - And actually talk to her.

So I will talk to her on this podcast actually. And she invited me like a week ago out to visit the farm in May or June or whatever. - Yeah, they have the farm up at the Oregon border. I haven't been there yet, but I've seen the pictures. And it's just beautiful.

- It looks awesome. And I was like, yes. - It looks beautiful. Let me know when you're going. - Yeah, let's go together. - You'll probably run there, but I'll drive there. - Yeah, but all that said, I do want to, 'cause a lot of people who are vegan write to me, and I do want to seriously, in the same seriousness that I approached keto, I do want to go on a few months to switch to a vegan diet at some point to really try it.

- I haven't done it yet 'cause I'm afraid I'm gonna function better. (laughing) I'm Argentine by my dad's side. And I don't eat meat super often, but well, for most people it would seem often. But I do love steak, I do. So I'm afraid I'm gonna feel better. - There's a social element to steak, you're right, 'cause coming from a Russian background, I can't imagine going to visit my folks, like my parents for Thanksgiving or something, and say, "Mom and dad, I don't eat meat." - Well, I think if you're gonna eat meat, getting it from sources that are compatible with continuation of the planet is good.

I mean, there are some real problems with the factory farm meat. You drive up and down the five and you pass that point where there are all those cows. I mean, as somebody who loves animals, it's clear that you wanna limit the amount of suffering of those animals. Whenever I hear about, we know people that hunt and that go and get their own meat, I really admire that.

I admire that people do that. We don't tend to do that in the hills around Stanford. There are mountain lines back there, but that's about it. And I'm certainly, I admire the vegan mindset of just making that decision. You're just not gonna consume other beings, but I haven't gone that way.

- For performance-wise, I'm just curious because I was surprised. I was certain that eating five, six, seven meals a day is the right thing to do if you wanna perform your best when I was like 20 or whatever. And I would eat oatmeal. Like I thought it's obvious I have to have a really, a lot of carbs in the breakfast.

I had a lot of preconceived notions. And then when I started eating like once a day, this was at the peak of my competing in jujitsu, it was like everything I know about nutrition is wrong. You realize that you have to become a scientist. First of all, you have to read literature, you have to learn, you experiment, but you also have to become a scientist of your own body.

In the same way, I have a lot of preconceived notions of what performance is like under a vegan diet. And I want to do it right, like seriously, not necessarily for the ethical reasons, but to see if it's performance-wise. Like can I, I remember there's like a fruitarian diet where you eat fruit only.

These extremes are like, they're pretty, they're interesting 'cause people have this need. The extremes are informative though, right? I mean, well-controlled experiments, you eliminate as many variables as you can except the one you're interested in. So people are running these experiments. I think that it's hard to imagine getting, I know people say you can get enough amino acids from plant-based sources, and I believe that.

I think it probably takes a little more work. One thing that's really clear is that the benefit of these omega-3, omega-6 ratios, like fish oils and things like that. There are some data that show that the, getting at least a thousand milligrams of the EPA, which is high in fish oils, but other things too, even some meats and other plants, in double, in matched placebo, double-blind controlled studies, placebo-controlled double-blind studies have shown that those can offset antidepressive symptoms as much as some of the selective serotonin reuptake inhibitors like Prozac and Zoloft.

So that's pretty impressive. And in Scandinavia, people know, especially in winter, to consume a lot of those omega-3s because they're good for you, they're good for the brain. - That's the other question. Nutrition-wise, what kind of stuff have you come across that's useful? Like I basically only take fish oil, like you said, electrolytes.

Electrolytes with water, the David Goggins diet. - Fish oil. - Plus fish oil. And then again, the sponsor, they made it so easier. The sponsor of your podcast and mine, athleticgreens.com/huberman. - Great stuff. - Support it. I don't know, like it's great stuff for sure, but also just takes away the headache of like, I don't have to think about.

- Yeah, you're going to get a bunch of vitamins and minerals. It does that. It sounds like a plug, but I have genuinely been buying it. No discount, no affiliation or anything since 2012. I think I heard about it on the Tim Ferriss podcast. I was like, oh, I'm going to try that stuff.

And I liked it. I mean, when I was starting my lab, I was working insane hours. I still work very long hours. And getting sick limits productivity. And I also wanted to train and I wasn't doing much training back then. Now I try and get three, four sessions in a week.

I'm not doing nothing like what you and David are doing or what Joe does. Or like you guys are way more regimented and consistent than I am. But I think that being healthy and feeling good is one of the great benefits to a career is having energy and just being not sick.

- Can we take a step back to sleep for a little bit? And so people should definitely look through your podcast the first five episodes were on sleep. Or no, I guess the first opening episode wasn't. - First one was sort of how the brain works generally. It was to give people some background.

And then we did four episodes on sleep. Including some stuff about food, temperature, exercise, jet lag, shift work for the jet lag folks and shift workers. - Yeah, it's like a masterclass on sleep. And then you're going on to a next topic in the next few episodes, which is incredible.

Well, neuroplasticity, we'll talk about it. But on sleep, one of the cool things about the human mind when it sleeps is dreaming. What do you think we understand about the contents of dreams? Like what do dreams mean? All the stuff we see when we dream. Is there something that we understand about the contents of dreams?

- Some of it is very concrete. So Matt Wilson, who MIT, showed in rodents and it's been shown in non-human primates. And now it's been shown in humans that there is replay of spatial information during sleep. So initially what Matt showed was that as these little rodents navigate through a maze, there are these cells in the hippocampus called place cells that fire when the animal encounters a turn or a corridor.

And that same exact same sequence is replayed during sleep. And it turns out this is true in London taxi cab drivers. Before phones and GPS were what they are today, the London taxi cab drivers were famous for knowing the routes through the city, through these mental maps and their analysis of their place cell firing during sleep and during wakefulness.

And so we are essentially taking spatial information about the location of things and replaying it during sleep. However, it's not replayed so that you remember it all. It's replayed so that if there's a reason to remember it, the links to the emotional system, to the components of the limbic system and hypothalamus that are relevant, like you got into a car crash or a particular location, or you lost a bunch of money because you were a cab driver, Uber driver, we'd say nowadays, and you were stuck at one particular avenue all day and frustrated.

You were getting yelled at by your spouse. That information gets encoded so that you never forget that at that particular time of day and that particular time of year and this thing happened. So context starts getting linked to experience. So there's spatial information that's absolutely replayed during sleep. And we experienced this sometimes as dreams.

The dreams that happen early in the night when slow wave sleep or non-REM sleep dominates, tends to be sleep of very kind of general themes and kind of location. It can feel a little bit eerie and kind of strange. Not so incidentally, the early phase of the night is when growth hormone is released.

In the '80s and '90s, there was a drug that was very popular. It's very legal now called GHB. You could actually buy it at GNC or a store then. I never took it, but it was a popular party drug. And some people, some famous celebrities died while on GHB.

They were also on a bunch of other things. So it's not clear what killed them, but GHB was very big in certain communities 'cause it promoted a massive release of growth hormone and gave people these very hypnotic states. So people would go to clubs and they were in these very hypnotic states.

It was part of a whole culture. That's early night. And those dreams tend to not have a lot of emotional content or load. That phase of dreaming is associated with the occasional jolting yourself out of sleep 'cause it's a somewhat lighter sleep. The dreams that occur during REM, during rapid eye movement sleep and that dominate towards morning are very different.

They tend to have very little epinephrine is available in the brain at that time. Epinephrine again being this molecule of stress, fear, and excitement. You are paralyzed during these REM dreams. You cannot move. There's intense emotion at the level of what you're feeling and there's so-called theory of mind.

Theory of mind is an idea that was put forward by Simon Baron Cohen, Sasha Baron Cohen's cousin. I think on the podcast, I mistakenly said that he was at Oxford. It's like the Cardinal sin. He's at Cambridge, forgive me. I'm not British, but. So the dreams in REM are heavily emotionally laden.

And it's very clear that those dreams and REM sleep, if you deprive yourself of them for too long, you become irritable and you start linking generally negative emotions to almost everything. The dreams that occur in REM sleep are when we divorce emotion from our prior experiences. And it's when we extract general rules and themes.

MIT seems to come up a lot today, but it's highly relevant. Susumu Tonogawa, Nobel Prize for immunoglobulin, but obviously fantastic neuroscientist as well, has shown that the replay of neurons in the hippocampus and elsewhere in the brain is kind of an approximation of the previous episode. And a lot of fear unlearning of uncoupling emotion from hard or traumatic events that happened previously occurs in REM sleep.

So you don't want to deprive yourself of REM sleep for too long. And those dreams tend to be very intense. Now, epinephrine is low so that you can't suddenly act out your dreams. But what's interesting is sometimes people will wake up suddenly while in a REM dream and their heart will be beating really, really fast.

That's a surge of epinephrine that occurs as you exit REM sleep. So you were having this intense emotional experience without the fear. You were essentially going through therapy in your sleep, self-induced therapy. It's like trauma therapy where you try and divorce the emotion from the experience. And then you wake up and some people also have the other component of REM, which is atonia, which is paralysis.

Pot smokers experience this a lot more than non-pot smokers. There's an invasion of paralysis into the waking state. I'm not a pot smoker, but I have experienced this. And when you wake up and you're paralyzed for a second, it's terrifying, but then you jolt yourself alert. So the REM sleep is important for kind of the self-induced therapy and forgetting the bad stuff.

It's good for uncoupling the emotions from bad experiences. And just there are two therapies, eye movement desensitization reprocessing, which is a eye movement thing that shuts down the amygdala during therapy, not during sleep. And ketamine, which is a dissociative analgesic. It's actually very similar to PCP. And ketamine is now being used as a trauma therapy when someone comes into the ER, for instance, and they were in a terrible car accident.

I mean, these are horrible things to describe, but you know, they saw a relative impaled on the driving, steering column or something, and they will give this drug to try and shut off the emotion system so that, because they're not going to forget, let's be honest. You don't forget the bad stuff, but it is possible to uncouple the bad events from the emotional system.

And there's all sorts of ethical issues about whether or not that's good or bad to do, but PTSD is a failure to uncouple the emotion from these intense experiences. - So the goal of this kind of therapy is in the uncoupling for that to be permanent, to separate. - So they can recount the event, and they can describe it without it triggering the same somatic experience of terror and dread, because those feelings can be debilitating, obviously.

- And you're saying physiologically in REM sleep, a similar process is happening. - That's right. That thematically, REM sleep is about experiencing or replaying intense emotions without experience, the somatic, the physical component of the emotion, either the acting out or the accelerated heart rate and agitation. Likewise, with things like ketamine therapies, that's the idea is you're uncoupling the physical sensation from the mental events.

- What is REM sleep and why is it so special? Maybe we can comment on that. Rapid eye movement sleep. - Yeah, discovered in the '50s at the University of Chicago, it's intense brain activity, high levels of metabolic activity, dreams in which people report a lot of the theory of mind.

We were talking about Simon Baron Cohen. Theory of mind was actually something that he developed for the diagnosis of autism. If you take kids, most kids of age five, six, seven, put them in front of a TV screen in a laboratory, and you have them watch a video where a kid is playing with a ball or a doll, and then the kid puts it into a drawer, shuts the drawer and walks away, and another kid comes in, and you ask the child who's observing this little movie, you say, "What does this second child think?" And a typical kid would say, "They want to play, and they don't know where the ball or doll is," or "They're upset," or "They're sad, they want the doll." Autistic children tend to say, "The doll's in the drawer.

The toy's in the drawer." They tend to fixate. They can't get in on the event. They can't get into the mind of the, they don't have a theory of mind. Dreams in REM have a heavy theory of mind component. People are after me trying to get me. You can assign motive to other people.

I'm afraid, but it's because there's an expectation. That doesn't tend to happen in slow-wave sleep dreams. Now, all this, of course, is by waking people up and asking them what they were dreaming about, which from a standpoint of a AI guy or a machine learning guy or a neuroscientist, kind of like, eh, but it's the best we've got.

But brain imaging in waking states while people view a movie and then brain imaging while people are sleeping supports the idea that that's basically what's going on. So REM sleep is amazing, and you're not gonna get much of it during your bout with Goggins, but you will afterward. - Why, so to comment, why won't I, so is it not possible to get into it real quick?

- Only if you're very, very sleep-deprived, but because you're going to be at high muscular output, that's going to bias you towards more slow-wave sleep overall. And your body and brain are smart. They, it will know, they will know that your main goal is to recover so you can keep going, so you can keep firing neuromuscular contractions and you can keep running so that you can, I mean, it's amazing to think, like, why do we ever stop?

Like, unlike weight training where I can't do a 500-pound deadlift, I just can't. I could train for it, but I certainly can't do a 600-pound deadlift. I can't do that. What causes us to stop an endurance event is usually not a physical barrier. It's almost always a purely mental barrier.

And that's a very interesting problem. I mean, neuroscientists don't tend to think about those sorts of problems 'cause it sounds so non-neuroscientific, but that's fundamentally related to the question of, you know, what is pursuit? What is the desire to push and to carry on? - Is there a neuroscientific answer for that question, you think?

- I think the closest thing is this paper from Genelia Farms, the Howard Hughes campus, showing that if you put animals into a simulated environment where you can measure their effort, the forces while they're running, and you can control the visual environment, and you can create a scenario where the animal thinks that its output is futile.

It thinks, it knows it's running and it's actually running, but you change the frequency of the stripes going by in their visual world, such that they think they're not getting anywhere, and eventually they quit. And the thing that determines whether or not they quit is a threshold level of epinephrine in the brainstem.

If you drop that level back down or you give the animals dopamine, essentially, they keep going. If you take dopamine down, they're like, "This isn't worth it. "It's helpless. "This isn't worth my time and energy." - But this is where the difference between humans and non-human animals is interesting 'cause it does feel like humans have an extra level of cognitive ability that might be relevant here.

- Well, you can pull from different time references. So if you're in that moment, you're gonna need a kit of things to pull from. So you can think this is in honor of someone else that passed away, and you will find a gas reserve that's amazing. Now, whether or not mice are like, "I remember my brother back in the other cage "when I was a little mouse." We don't know, but it's very likely that they don't do that, that they're so present, they're in the experience of there and then and now, that they aren't able to extract from the past, and they're not able to project into the future, like how great it's gonna feel when I get to the end of this really lame VR corridor.

I don't think they think about that. - And think about like, if I quit now, how will that have, what kind of effect will it have on the rest of my life in the future difficult times? Like if you allow yourself to quit in this particular moment, you'll become a quitter more and more in life, and then you're going to not get the other nice, the opposite sex mammals.

- That's pretty severe. You went there, you took it the whole way to evolution and back again. I mean, but that's really it. I mean, our ability to time reference in the past, present, or future. I do believe that we can be in the present and the past, or the present and the future, or only in the present, or only in the future, or only in the past.

But I don't think that we can really think about past, present, and future all at once. And this has a similarity to covert attention. Like we can split our visual attention into two things. We really can do a task, even though we can't multitask. Or we can bring those two spotlights of attention to the same location.

But it's very hard to split our attention in really well into three domains, excuse me, into three domains. I think that that's very, very challenging. And our time referencing scheme tends to be just one or two time references. - So Lisa Feldman Barrett, I'm not sure if you've done work together, but at least you're-- - I found out about her because of you and your podcast with her.

And I brought her onto Instagram, did an Instagram Live about emotion. And it was fascinating. And she's a very spirited and very, very smart woman. - Fearless and brilliant. So I love her, she's amazing. She's not a scholar of hallucinogens or dreams, but she had this intuition that there may be a connection between the kind of dissociation that happens in dreaming and that happens in like psychedelics.

Because of my previous conversation with you on this podcast, Matthew Johnson from Johns Hopkins reached out and he said, but he commented, I think, on something that we commented on, I don't even remember exactly what, but that there's not many studies, it's not being psychedelics and not being rigorously studied in an academic setting, like with a full rigor of science.

And he said, "Well, actually, "that's exactly what we're doing "and they're extremely well-funded now." And it's been a long battle to get it accepted as a serious scientific pursuit. So, but, and I'd like to ask you a little bit about that. Do you have a sense about connection between dreams and psychedelics or these different explorations of mind states that are outside of the standard normal one, that's the wake mindset?

- Yeah, I loved your discussion with Matthew. I knew of the Hopkins group and the stuff they were doing, but I didn't know much about it at all. And I learned a ton from that podcast. I reached out to him just to say, "Love what you're doing, I think it's incredible." So yeah, your podcast has been a great source of serious academic and intellectual conversation for me.

I think what they're doing at Hopkins is amazing. He has a collaborator there, actually, they had a very popular paper I just throw out there for fun, who was a postdoc at Stanford. Her name is Gule. She's Turkish, I believe. And I apologize, her last name escapes me at the moment, but that's just a function of my brain.

She had a paper showing that she put octopi on MDMA, on ecstasy and found out, this was published in Current Biology, it was a great journal, showing that the octopi then wanted to spend more time with other octopi, and they started cuddling. So they're colleagues out there. But the Hopkins project is super interesting because I think they were initially supported mainly through private philanthropy.

And now you're starting to see some more interest at the level of NIH about psychedelics. It's a complicated space because the psychedelics are always looked at through the lens of the '60s and people losing their mind. I always say, you don't want a Ken Kesey out of the game.

Ken Kesey was amazing, right? Part of the whole beat generation thing. And he was actually at the VA near Stanford. That's where he eventually, in Menlo Park, he wrote "One Flew Over the Cuckoo's Nest," or maybe that was about him. Anyway, the comments will tell me how wrong I am, but I think I'm tossing these words in the right general direction.

But Huxley, Kesey, they did a lot of LSD and they all lost their jobs, right? They lost their jobs at big institutions like Harvard and Stanford and elsewhere, or they left because they made themselves the experiments. Hopkins, as far as I know, is one of the first places, if not the first place, where whatever Matt may or may not be doing in his own life, I don't know, it's really about the patients and whether or not the patients in these institutional review board approved studies, whether or not they're getting better in situations like depression.

I think it's clear that there's a very close relationship between hallucinogenic states and dreaming of the sort that would describe for REM dreaming. And there's a terrific set of books and body of scientific literature from a guy named Alan Hobson, who is an MD, is at Harvard Med, and he wrote books like "Dream Drugstore." One of the first neuroscience books I ever read was about hallucinations and how psychedelics and dreaming are very similar.

That was way back when I was in high school, I was just curious. And he really understood the relationship between LSD and REM dreams and how similar they are. I think psychedelics, and Matt knows way more about this than I do, of course, but psychedelics have some very interesting properties.

They are certainly not for everybody, right? And kids, it's a problem. I think the major issues right now around the psychedelic conversation is that it's clear that they can unveil certain elements of neuroplasticity. They make the brain amenable to change, changing up space-time relationships, changing up the emotional load of an event and being able to reframe that.

It's clear that happens. But there's two major issues. One is that people talk about plasticity as if plasticity is the goal, but plasticity is a state within which you can direct neurology. And the question is, what changes are you trying to get to? So people are just taking psychedelics to unveil plasticity without thinking about what circuits they want to modify and how.

I think that's a problem. I think there's great potential, however, for people opening up these states of plasticity with psychedelics or otherwise and directing the plastic changes toward a particular endpoint. And there's an absolutely spectacular paper at a UC Davis, published as a full article in Nature just a couple of months ago, showing that there are psychedelics that are now can be modified.

So chemists have gotten into the game now and modifying to take away the hallucinogenic component where you still get the neuroplasticity components. And for a lot of people, it'd be like, oh, that's no fun. That's not giving you the wild experience. But I do think that that holds great potential for people that wouldn't otherwise orient towards some of these drugs.

So I think it's really marvelous what's happening and what's about to happen. And I think there is one drug in that kit of drugs that's very unusual, like psilocybin, LSD, those promote heavy, heavy serotonin release and lateralized connections ramp up, et cetera. Matt talked about all that. But MDMA, ecstasy, is a very unusual situation where dopamine is very, very high because of the way the drug is designed.

Dopamine release, it goes through the roof. So people feel great and they want to move and they have a lot of energy. But serotonin levels are also high. And that's a very unnatural state. And why MDMA may, and I want to highlight may, have particularly high potential for the treatment of certain forms of depression is an interesting question because never before, as far as we know in human history, has there been a possibility of opening up dopaminergic and serotonergic states at the same time, dopamine being the molecule pursuit and reward and more and more, and serotonin being one of bliss and being content right where you're at.

So it's almost like those two things wrap back on themselves and create this very unusual state. And I think the bigger conversation is what to do with a state like that. Like, do you, is it about self-love? Is it about developing love for another person? Is it about forgetting hate?

Like, these are powerful molecules. And I think if the academic community and the clinical community is going to move forward with them in any serious way, I think there needs to be a conversation about what they're being used for. - Right, and coupled with that, I think similar to what you're saying, like Matt has talked about, as others have talked about, some of the biggest benefits of progress, whether it's quitting smoking and all this kind of stuff, is in the days after, it's the integration of the experience.

So maybe you open up the brain to the neuroplasticity, but then there's work to be done. It's not, you're like, you shake up something in the biology of the brain, but you have to do then its work. - Absolutely. Now, a friend of mine who's a physician, he says, who's quite open to this idea that psychedelics could play a real role in real medicine, says, "Better living through chemistry "still requires better living." And I think it's a beautiful statement.

I wish I had said it, but he gets the credit. But the plasticity window opens, and then as you said, what are you going to do in the two weeks, three weeks, four weeks afterward? Because that's the real opportunity. But those psychedelic experiences are really a case of an amplified experience inside of an amplified experience, so much so that everything seems relevant.

And it's fascinating. I mean, my hope is that the AI and machine learning and the brain machine interface and all that will eventually be merged with the psychedelic treatments so that an individual can go in, take whatever amount of whatever's safe for them, working with a clinician, and really direct the plasticity while maybe stimulating the medial orbital frontal cortex, or increasing the observer, or decreasing the observer in the brain, or decreasing the amygdala.

I mean, it's doable. It's doable with transcranial magnetic stimulation, and it's for shutting down activity, and it's doable with ultrasound. Ultrasound now allows very focal activation of particular brain regions through the skull noninvasively. - So it's approaching the same kind of therapy from different angles. One of AI's is the computational side, sort of injecting the robotics, injecting, maybe you can even think about it as electricity, the electrical approach, versus then the chemical approach.

- Absolutely, and then the psychology is subjective, right? So it's gonna take some real understanding of what that person's lexicon is. Like, you know, that wasn't a pun, sorry. (laughing) Sorry, terrible. I'm like the worst. That's the one thing I know from the feedback on my podcast. My jokes are terrible, but I never claim to be funny.

(laughing) But somebody who they really trust and understands when somebody says, you know, for a very stoic person, like I'm imagining you interviewed the great Dan Gable, right? I don't know anything about Dan, but can you imagine, like, you asked Dan, like, you know, how you feel about something while on one of these drugs?

And like, I mean, his languaging might, if he says that was troubling, it might mean that it was very troubling or not troubling at all. So people are, language is a poor guide because if I say I'm upset, how upset is that? Well, that's very subjective. So you need, we need, can you build a tool for that?

Can you build an AI tool for that? - Yeah, deeper, yeah, well-- - Maybe that's the eye, maybe that's our, that's what the eyes could reveal. - So language is not just words, it's everything together. And that's one of the fascinating things about the eyes and the window to the soul.

I mean, they express so much, the face, the eyes, the body. I mean, Lisa talks about that, the communication of emotions. It's a super complex. Perhaps it's a bit of a side fun tangent, but Matt, Matthew Johnson brings up DMT. And the experience of DMT is, from a scientific perspective, just a mystery in itself over its intensity of what happens to the brain.

And of course, Joe Rogan and others bring it up as a very different, special kind of experience. And elves seem to come up often. - I've never tried DMT, what allows for hallucinogenic states. And it, I mean, DMT is a really interesting molecule. There are a lot of people experimenting now with DMT.

And they just, the way they've described it is as a kind of a freight train through space and time. Very different than the way people describe LSD type experiences or psilocybin, where time and space are very fluid, but it tends to be a kind of a slower role, if you will.

So it's clear that DMT is tapping into a brain state that's distinctly different than the other psychedelics. And you mentioned jujitsu and these other communities. I mean, it's, I think it's interesting because jujitsu is a nonverbal activity and people get together and talk about this nonverbal activity and they show great love for it.

In the same way that surfers, you know, I've known some surfers in my time and they will get up at the crack of dawn and drive really, really far to sit in the water and wait for this wave to come. I have to imagine it's pretty fantastic. I think that human beings now, some of whom are in the scientific community are starting to feel comfortable enough to talk about some of these other loves and other endeavors, because they do reveal a certain component about our underlying neurology.

I'm fascinated by the concept of wordlessness, activities in which language is just not sufficient to capture and in which feel so vital as a reset, as important as sleep. You know, I think that's one of the dangers of the phone is not that you're gonna get into some online battle or that you're always staring at the phone, is that it's a words.

Whereas we read things, we're hearing the script in our head and I think getting into states where we are in a state of wordlessness is very renewing and replenishing and just can feel amazing. And I believe also can help us tap into creative states and allow our neurology to access creative states.

And sleep is one such wordlessness period. So one of the most interesting things to me are states that one can approach in waking, non-sleep depressed, wordlessness through, maybe it's jujitsu, maybe it's for some people surfing, maybe it's dancing, maybe it's just, I don't know, staring at a wall, who knows.

But where the language components of the brain are completely shut down. And it has to be the case that drugs are no drugs, that the brain is entering and starting to states and starting to use algorithms that are distinctly different than when we're trying to compose things in any kind of coherent way for someone else to understand.

There's no interest in anyone else understanding what you're experiencing in that moment. And that's beautiful. And I think it's not just beautiful because it feels good, I think it's beautiful because it's important and it's clearly fundamental to our neurology. - And your sense is there's a connection between dreams and DMT and psychedelic, like all of the, you can understand one by studying the other.

So for example, dreams are also very difficult to study, but they're more accessible, it's safer to study. - And we're told we need to get more of it. Whereas with psychedelics, there's this big question mark, is it gonna make everyone crazy? Is it gonna be legal? I mean, it's kind of interesting how, if one looks on Instagram, one could almost think that these drugs are already legal based on the way that people commute, but they're not yet.

There's still a lot of them are scheduled. - And there's a lot of questions. I mean, but nevertheless, it's like, my hope is that science opens up to these drugs a little bit more. It's just, I have this intuition that, like a lot of people share that they would be able to unlock deeper understanding of our own mind.

It's any kind of, same as studying dreams. - Absolutely. - So creativity is in the nonlinearities, right? But productivity is in the implementation of linearities. I mean, that's what is absolutely clear. This is why I think we were talking earlier about why a formal rigorous training in something where other people are looking at you and telling you, "No, not good enough, go back and do it again." There's real value to that because otherwise, it's just ideas, it's just vapors.

- You know, one thing that Matt mentioned as the study that they're working on is, as opposed to, I think most of the psychedelic studies they've done is on how to treat different conditions. And one of the things they're working on now is to try to do a study where, for creatives, for people that don't have a condition that they're trying to treat, but instead see how this, how psychedelics can help you create.

So like-- - Goodness, if you take creatives and you give them more psychedelics, they're not gonna be able to get out of their room. - I don't know. Well, but this is the, maybe you can speak to that, psychedelics or not, or dreams or tools in general, how to be better creatives.

That's an interesting, I don't often see studies of this nature of like how to take high performance in the mental creative space and get them to perform even better. So it's not average people, it's like masters of their craft, like taking, I mean, his examples was taking an Elon Musk, which is in the engineering space, and maybe musicians and all that kind of stuff, and studying that.

I mean, that's weird. Usually the science, the scientific exploration there has been done by the musicians themselves, as has been documented. - Like jazz is like all nonlinearities, right? But the people still have to know how to play their instruments, right? There's some early skill building that's critical. I mean, when you mention someone like Elon, I mean, he's already a virtuoso, right?

'Cause he, and in so many different domains, I've never met him, but it's clear, right? It's not just that he's ambitious and bold and brave and all that, it's all that. And there's clearly a different way of looking at the same problems that everyone else is looking at. And people are probably banging their head against the refrigerator, thinking like, think differently, it doesn't work that way.

It involved, there's a certain anxiety in, for the, I'm not talking about for Elon, but I have no idea. But I think for somebody who's very structured, very regimented, very linear, the anxiety comes from letting go of those linearities. And for the person that's very creative, the anxiety comes from trying to impose linearities, right?

The really creative artists or musician, they seem nuts, they seem like they can't get their life together because they can't. And we look at people who are kind of pseudo Asperger's or Asperger's or some forms of autism, and they are so hyper-linear, but you take away those linearities and they freak out.

And that's kind of the essence of some of those syndromes. So I think that the ability to toggle back and forth between those states is what's remarkable. I mean, because we're here and we're having this discussion, I mean, Steve Jobs is a good example. He probably the best example, somebody who actually talked about his own process, about the merging of art and science, art and engineering, humanities and science.

Very few people can do that. You seem to have a capacity to do that. Like you know poetry and you are AI guy, like there's nothing linear about poetry as far as I can tell. - I mean, I do wonder just like we've been talking about if there's any ways to push that to its limits to explore further.

I don't like leaning, this is why I'm bothered there's not more science and psychedelics I haven't done almost, so I've eaten mushrooms a few times allegedly, but that's it. And the reason I don't do more, the reason I haven't done DMT is because it's illegal and it's like not well studied.

I'm in those things, I'm not usually at the cutting edge, but I'm very curious and it feels like there could be tools to be discovered there, not for fun, not for recreation, but for like encouraging whether you're a linear thinker to go non-linear or it's non-linear to go linear, like to shake things up.

You mentioned Dan Gable, the idea of Dan Gable on psychedelics is fascinating to me because he's such a control freak. I mean, he lets control-- - That I would show up for. That I would show up for. - But like so much of these psychedelic experiences it feels like is for letting go.

- That's right. - To resist. - But that's supposedly where the growth is in giving oneself over to the process. - And that's for people who are like master controllers, he's one of the greatest coaches of all time, it's fascinating to see what that battle looks like of resistance and then of letting go.

Yeah, I mean, I can't wait to see where these studies take us. - Well, it's clearly happening. You know, I've asked, I have a couple of colleagues at Stanford who are doing animal studies. I've asked around, you know, there's a lot of discussion in the neuroscience community about what the perception of a laboratory is if they work on psychedelics.

I mean, I have to tip my hat to the folks at Hopkins, they are pioneers. And as Terry Signowski, he's a computational neuroscientist down at Salk says, I don't think he was the first person to say this, he says, you know how to spot the pioneers? They're the ones with the arrows in their backs.

- Yeah. - And you know, it's an unkind world to a scientist that's trying to do really cutting edge stuff. My colleague, David Spiegel, who studies medical hypnosis, he's got dozens of studies now showing that hypnosis can be beneficial for pain management, anxiety management, cancer outcomes. And it's finally, you know, at the point where there's so much data, but people hear hypnosis and they think of stage hypnosis, which is like the furthest thing from what he's doing.

And I think mind body type stuff, hypnosis, respiration and breathing, I think the hard science walk into the problem is always going to be best to get the community on board. And then it's up to people like Matt and to really, you know, take it to the next level.

And as I say, not Kesey out of the game, because Kesey basically was taken too much of his own stuff and he started dressing crazy, a banana hats. And like you see him, he had the magic bus. So, you know, the day I start driving to work in the magic bus, that's the day I lose my job.

I'm not into buses or wearing fruit, but- - You're going to get a phone call from me and I hope you do the same for me. It's like, dude, what are you doing? - Well, what's interesting earlier, we're talking about the challenge with David that you're about to do.

I mean, that is a psychedelic experience of sorts because you're biasing your mind towards a pretty extreme neurochemical state and you don't know what you're going to find there. And that's kind of the excitement, at least for me as an observer. It's like, I want to know what the experience is like afterward.

I want to know, like, how was it? I mean, I'm sure you're going to get something. Like you said, you're going to grow. The question is how. - And not resisting. I mean, it's the same as with a psychedelic experience. It's like not, like giving yourself over completely to the experience and not resisting and going through the whole mental journey of whether it's anger or excitement or exhaustion, the whole thing.

It's, I mean, that's the entirety of the process that David goes through when he does his own challenges and so on, is that whole journey. He finds purposely, like, missile seeks the limits of the mind that whenever the resistance is felt, runs up against it, and then goes through the full journey of going beyond it and seeing what's there on the other side.

- Well, stress has these two sides, the limbic friction of being tired and needing to get more energized. That's one form of stress. And then there's the feeling too amped up and needing to calm down. The typical discussion around stress is one thing, but it's all limbic friction. It's just that when I say limbic friction, that's not a real scientific term.

I just mean the limbic system wanting to pull you down into sleep or wanting to put you into panic. And you using top-down processing, using that evolved forebrain to say, "Mm-mm, I'm not going to go to sleep." And, "Mm-mm, I'm not going to freak out." And those top-down control mechanisms are, I mean, when those get honed, that's beautiful because then you're increasing capacity for everything.

- This month on the podcast, you're talking about neuroplasticity. You mentioned it a bunch already. Is there something you're looking forward to specifically, like something maybe you're fascinated by that jumps to mind about neuroplasticity, this fascinating property of the brain? - Yeah, I think that it's clear there's one facet of neuroplasticity that is very well supported by the research data that hardly anyone has implemented in the real world.

And that's the release of acetylcholine from these neurons in the forebrain called nucleus basalis. This is mainly the work of Mike Merzenich, who used to be at UCSF, and some of his scientific offspring, Greg Reckin's own, and Michael Kilgaard and others. What they showed was increases in acetylcholine, this molecule associated with focus, in concert, meaning at the same time as some event, motor event or music event or any kind of sensory event, immediately reorganizes the neocortex so that there's a permanent map representation of that event.

And I absolutely believe that this can be channeled toward accelerated skill learning. And my friend and colleague, Eddie Chang, who's now the chair of neurosurgery at UCSF, but also a fine scientist in his own right, not just a clinician, he's doing studies looking at rapid acquisition of language using these principles.

He trained with Merzenich. It's clear we have these gates on plasticity in the forebrain, and they are gated by nicotinic acetylcholine transmission. And why that hasn't made it into protocols for motor learning, sport learning, language learning, music learning, emotional learning, I don't know. I think part of the reason has been kind of cultural is that scientists publish their paper and they move on.

Merzenich talked a lot and still can be found from time to time talking about how these plasticity mechanisms can be leveraged. But he had a commercial company, and so then people kind of backed away from him a little bit. I think he was, to be honest, I think Merzenich was ahead of his time.

And I think the timing is right now for people to understand these mechanisms of plasticity and start to implement them. Also, it all sounds like becoming superhuman or optimizing or whatever, all that, yes. But also what about kids with language learning deficits or with dyslexia or just performance in school in general?

I mean, I have a deep interest and concern for the future of science and mathematics and not just in this country, but all over the world. And more plasticity equals faster, better, deeper learning. And if we don't do this, I don't think we're going to get the full reach out of all the machine learning tools either, because everyone talks about these huge data sets, but those huge data sets funnel into human interpretation.

I mean, we don't just like stare at the numbers and bask. So the human brain, I think, needs to leverage these plasticity mechanisms to keep up with the thing that's happening very, very fast, which is technology development. So that's a long-winded way of saying basal forebrain cholinergic transmission and plasticity, it allows for plasticity in adulthood and it allows for it in single trial learning, which is incredible.

- But how do we leverage that? Like in the physical space taking actions, or is there some chemicals that can stimulate, stimulate neuroplasticity? Like what- - I think it's the intersection of the two. I think it's being engaged in a physical practice while enhancing pharmacology. And it has to be done safely.

- And this is full of open questions. This is the very beginnings of it, like you're saying. - Yeah, a pill that's safe that increases nicotinic transmission. I mean, I know a number of people that chew Nicorette. Actually, I have a Nobel Prize winning colleague at Columbia, not to be named, who chews like six pieces of Nicorette in a half hour conversation with him.

And he started doing that as a replacement for smoking, because smoking is nicotine, nicotinic stimulation of the cholinergic system. So smokers have long known that increases focus and attention and learning. It's just that the lung cancer thing is a barrier. Now I'm not suggesting people take Nicorette, but it's clear that we need better directed pharmacology.

But you can imagine next time you go in for a learning bout, if it's really essential, you might want to stimulate the nicotinic system if that's safe for you. Again, I'm a doctor. So again, I'm not telling people to do this, but that's where it's going. Until we start merging machines with pharmacology and behavior, we're just kind of walking around in a circle over and over again.

And it's gonna happen. - Do you find computer vision, machine learning, from the perspective of tooling, as an interesting tool for analyzing, for processing all the data from the neuroscience world, from the neurobiology, biology, the chemical, all the different data sets that you could have about the mind, the eye, everything that's neck and above, and also the central nervous system and all?

- Absolutely. I think that computer science and engineering and chemistry, bioengineering, that's what's creating the acceleration and progress in neuroscience right now. I think it's actually one place where science, I'm very reassured, science has invited in psychologists, computational biologists, at least at Stanford, MIT, and other places too, of course, it's clear that it's a everyone's invited kind of party right now.

That the major issue in the field of neuroscience, at least through my view, is that there's no conceptual leadership. No one is saying we need to work on and solve this problem or that problem. It's very fragmented right now. Now, the good news is people are communicating. So computer scientists and people who work on AI, machine vision, are talking to biologists and vice versa.

But it's very dispersed. - Is there a lot of different data sets? Like in your work that you've just come across, is there a huge number of disparate data sets around neuroscience and so on? - Well, there's a lot of cell sequencing stuff. So the Broad over in Boston, and then on this coast, the Chan Zuckerberg Initiative, what they did, $3 billion to sequence every cell type in humans and in animals.

And I think their goal is to cure every disease by some date, I don't know, in the future. Huge data sets of gene expression and protein expression. That's valuable. I think no one really knows how to think about neural circuits and what is a neural circuit. Is it one structure?

Is it two structures communicating? I think this is where I actually think that the robotics is going to tell us how the brain works. Because it's tempting to think that the brain has all these cell types and circuits in order to solve specific problems. But it might be that the fundamental algorithm is to create cells and circuits that can solve variable problems.

We know in the retina, just a very simple example is that we've always heard about like cones are for color vision and high acuity, and rods are for night vision and non-color vision. But at the dusk, dawn transition, certain cell types switch to do completely different, have a completely different function for viewing starry night versus what they do during the daytime.

So neurons multiplex. And I think building machines that can multiplex and can evolve themselves is going to help us really understand what the brain is doing. We need to tease out the fundamental algorithms. We know they're like motion detection and spatial vision and things like that. I think machines are going to be much faster at that than our understanding of biology and how the brain does that.

Basically, I'll be out of a job and people like you will have a job. - Well, no, I think the main idea is that there won't be a job that's machine learning or computer vision. It's just, it's a tool that neuroscientists will use more and more and more. And biologists would use.

I mean, this whole idea that it will just be a tool that allows you to start expanding the kind of things you can study. - Well, the next generation coming up, I can say this 'cause I now I'm blessed to have a bioengineering student. They think about problems so differently than biologists do.

We realized the other day, we both came up with a set of ideas around a certain project and we realized that her version of it was the exact opposite of mine, and hers was far more rational. It's just an engineering perspective. It's like, why would we do that last?

We should do that first. I think that the next generation is really interested in solving practical problems. So a lot like computer science and engineering was in the late nineties, it was like, you can go do a PhD in computer science and engineering, maybe, or you go work for a company and actually build stuff that's useful.

I think neuroscientists and people interested in neuroscience are starting to think, how can I build stuff that's useful? And this is statement is supported by the fact that many people in my business leave their academic labs. Fortunately, not all of them, but they leave their academic labs and they go work for companies, like Neuralink.

- Like Neuralink. This is something I think we've spoken a few times offline about, as in speaking of computer vision, I'm fascinated by the eye. I did a bunch of work on the eye. So from, there's the neuroscientist, there's a neurobiology way of studying the eye, and there's the computer vision way of studying the eye.

And the computer vision way of studying the eye, of just like observing, non-contact sensing of humans, is really fascinating to me. And studying human behavior in different contexts, like in semi-autonomous vehicles, it seemed like there's a lot of signal that comes from the eye, that comes from blinking, that's not fully understood yet.

It's been in the lab, it's been used quite a bit to study like the dilation of the pupil, all those kinds of things we're used to infer, workload, cognitive load, all those kinds of things. But the picture is murky. It's not completely well understood, especially in the wild, how much signal you can get from the eye, from the human face.

I've downloaded Joe Rogan's, all of the podcasts he's ever done, video. - You have the YouTube bank? - I have the YouTube bank. For a reason that, this was before he went with Spotify. - You own the archive. There's PubMed, and then there's the Joe Rogan experience owned by, or maintained by Lex.

- Yeah, privately, for my private collection. No, the reason I did it, and I did the really rigorous processing of it, which is like, I extracted all of the faces, I did the really good blink track, the pupil tracking and the blink detection for the entirety of the, oh, I should say it's from episode, I forget what it is, but it's like episode 900 when they switched to 1080p video.

It was like much crappier video. It's still kind of-- - Did you log when there was marijuana consumption or when they were drinking? - When there's smoke, I mean, there's so many-- - 'Cause that's gonna, like, it won't throw off the data, but it's relevant to the-- - It's relevant to the context.

- The pupil data. - So let's just put it this way. There's a lot of fascinating computer vision problems involved, but I only kept long sequences of data where the eyes detected exceptionally well, and I also removed people that were wearing glasses. I removed, there's certain people that have a way of moving their eyes and squinting where it's harder to infer, like, concrete blinks.

You know, they'll kind of have a squint the whole time, and their blink is very light. It's very tough to know what's an actual blink. - And you got those baseball cap wearing guys. There are certain people that go on podcasts and wear baseball caps and don't reveal their, I don't know if they realize it or not until it comes out, but their face is completely obscured from vision.

- And from a computer vision perspective, people that wear makeup, and usually women and their eyes, it complicates things. Like, eyelashes, all complicate things. So, you know, you can clean stuff up just so you have really crisp signal. You don't have to. You can deal with issues, but, you know, there's so many hours of Joe Rogan video.

Anyway, I say all that because I was searching for an interesting personal experiment for me 'cause I saw in drivers, when I was looking at eye movement in drivers, it seemed to indicate, there seemed to be quite a lot of signal there that indicates amount of cognitive load. But it's not clear if there's something conclusive.

But if there is some signal that's a really powerful one because eye movement can be detected in the wild, like you and I sitting here, I can detect eye movement really well. Pupil dilation is a really crappy indicator. - And it's luminance dependent. Like if I turn toward a light, it's a route.

People change size depending on level of alertness or autonomic arousal, but also overall levels of luminance. It's very, very hard. But there are, I mean, you're sitting on a gold mine because there is a lot of interest right now in measuring state through non-contact sensing. Heart rate variability through changes in skin tone, but just off a camera, can you imagine that?

The point where you just look at some video and you're like, oh, they're getting more stressed or worked up and they're not, based on a heat map of some little patch on their face. 'Cause everyone's gonna have this slight, sort of compartmentalize it slightly differently, but you can learn it pretty quickly.

We know this when someone's like giving a talk and we see them starting a blotching on their neck. You know, this is the thesis defense response, right? We know it and it's a stressful situation 'cause not passing your thesis defense is rough. And we can see that, but cameras can pick that up really easily at much lower levels than the blatant blotching kind of effect.

And eye movements certainly are powerful indications of the state of the autonomic system. - So what do you, do you think there are things from a high level that you can pick up from eye movement and blinking? - Well, blink frequency is gonna increase as people get tired, right?

I mean, I've actually been teased a lot online 'cause I don't blink much when I'll do a post. And so I did a whole post about blinking, about the science of blinking. There's some data, very strong data, not from my lab that show that every time you blink, it resets your perception of time.

They have people do these kind of track up kind of a Doppler like thing. And anyway, blinking resets your perception of time. There's a dopaminergic mechanism in the blink related circuitry of the brain. When people are very alert, they tend to not blink very much. When we're sleepy, we tend to blink more and our eyes tend to close.

Now, some people are more hooded in the way their eyes sit. Some people are like this all the time. There are some very famous people. I'm not gonna name them because I might run into them at some point who are like accused of being sociopaths 'cause they don't blink very often.

But they might just have high levels of autonomic arousal. They just don't blink very much. Also depends on how lubricated the eyes are. So I think within individual, you can get a lot of information. I don't think we can say this person's blinking a lot. They're lying, this person or they're tired.

This person doesn't blink. They're stressed. I think if you understand that person's baseline, you can get it. And presumably, well, having been on the Joe Rogan experience, I can say when you first sit down there, if you've never been in there before. - You're in my dataset, by the way.

- Oh my. Well, I bet you, I will admit to being, first time sitting down there. I mean, Joe is incredibly gracious, made me feel very comfortable there. But yeah, it's an intense experience. It's a small space too. Anytime you enter a small space from a big space in his old studio, you're familiar with.

There's a breaking in period where you're getting to know somebody. And so I'm sure my levels of autonomic arousal front of the podcast were higher than later. But once you have a baseline established, you can get a lot of data on somebody simply from blinks. Some people averting gaze too.

If you have both people, that's really powerful. This is the Holy Grail, another Holy Grail of neuroscience. We've mainly looked at subjects in isolation. There hasn't been much brain imaging of two people interacting, or even in animal models of two mice or two monkeys interacting. It's all like person scanner, bite bar.

I mean, if you've ever been in one of these scanners, you're like in a bite bar. It's very medieval. - And so you think in the interaction, there's actually, you can almost study them as a single brain or as a single system. The two brains are a single system.

- I think with AI- - Highly correlated. - Yeah, maybe are your blinks triggering my blinks? Like, you know, are your non-blink epochs, you know, extending my non-blink epochs? There's a fascinating space to explore there and no one's done it. And 'cause everyone let the Joe Rogan Experience archive disappear except for you.

You grabbed- - Well, actually- - Did you get the comments too? Because I think the comments were almost as entertaining as the conversation. - You know what you just made me realize with the couplings? I have a better data set than the Joe Rogan podcast with high resolution video, which is the raw video for this podcast.

So for example, both cameras right now are recording you and I full feed. The final result will switch cameras back and forth, but I have the full feed. So I can have the blinking for both you and I the whole time. - I bet you people trigger blinks in one another, you know, and there's also like the simplest way to think about the blinks and the attentional thing and the alertness is two fighters in the standoff.

There's this whole lore around who blinks first. - Yeah. - It's like, they blink first. Well, what are we really asking? They're asking whether or not one person can maintain focus longer than the other person, which is an important parameter. It's not the only parameter, but it's an important parameter.

And so that blinking contest, even though they don't square off as a blinking contest, it's well known that the first to blink is revealing something about their capacity to hold attention. - You've started an amazing podcast that we've mentioned a few times. People should definitely check it out. It's called the "Human and Man Lab Podcast." It does your, it's basically, it embodies the personality of Andrew Kuberman, which is like, makes science accessible, but also fascinating and giving it, like, what do you call it?

You give tools for everyday life, meaning it kind of grounds it in like, what the hell does this mean for my life? But then also does the beauty of science at the same time. So I love both the rigor and the openness of the whole thing plus the whole corrections thing that we mentioned.

Anyway, what's been the hardest part of this whole process? You're one of, already, one of the only, and one of the best science podcasters out there. So in that process, what's been the hardest, what's been the most exciting part? - Wow. Well, first of all, thanks for the kind words about the podcast.

It was inspired by you. I absolutely, that's no BS. The last time we met to do an interview for your podcast, we talked a little bit about it, and you gave me the subtle nudge that maybe there was a podcast there, and I thought about it, and I left, and I was just like, I got to do this thing.

And you really gave me the encouragement to do it. And your podcast, this podcast, has really forged the way. You've been tip of the spear on serious, scientific, intellectual, yet fun, accessible conversation. And so I, as your colleague and friend, but just even if those things weren't true, like this podcast was and is the inspiration.

There's no question. - Thank you so much. - Yeah, I really, like 100%. And when I decided to do the podcast, the Huberman Lab podcast, I thought really long and hard about what would work best and would be most beneficial. Turned out to be the hardest thing, which is to stay on a single topic for three or four more episodes before switching to a new topic.

Because I know from the experience of university and teaching in university, as you know as well, that there's always the temptation to pivot to something else, but the drilling into something really deeply is where the gems reside. And the challenge has been how to make it interesting, how to keep people on board, how to give people tools along the way, but also stay close to the scientific data.

I like to think that we're headed in the right direction. It still needs to evolve, but that's been a challenge. I think I also am challenged by the fact that there's a tremendous range of backgrounds of listeners. So some people have asked for more names, like more bits and parts of the nervous system and cellular molecular mechanisms and all that kind of thing.

And other people have said, "I don't understand any of that stuff, but I think I'm keeping up." And so unlike a university course where there are prerequisites and everyone's coming to the table with more or less the same knowledge, I have a very limited sense of what the audience knows and doesn't know.

So that's why I incorporated the feature of the comment section on YouTube being a source of feedback. And I do a kind of an office hours-like episode every third or fourth episode where I address common questions. And I think that the podcast space in my mind, at least for the sort of podcasts I'm doing, needed a venue for the listeners to be a more integral part of the experience as opposed to just commenting on what they liked or didn't like.

So while I like to hear what people liked and didn't like, I also really like to hear about, "Hey, tell me more about temperature minimums and how they can be used to phase shifts, circadian rhythms, or whatever it is." And I realized that I'm probably losing some people along the way, but hopefully at the end of each month, and because of the way that the episodes are archived, people will come away feeling as if they've learned a ton and they have tools that they can implement.

And perhaps most importantly, that they're starting to think scientifically about the tons of other stuff that's out there. So that's been the challenge, and it's still really early days. But, and of course there's also an attentional challenge. I realize that people are busy. Not everyone has two hours to listen to a podcast about jet lag and shift work, and raising kids and sleep and that kind of thing.

I'm not raising kids, but I did a whole thing about babies and sleep with, you know, and how parents can manage their sleep when kids aren't sleeping. So it's been, I'm hacking through the jungle of all this stuff, but, and I'll come right back to, my inspiration and my North star on this is getting to a point where the audience that listens to this feels the same way that I do when I listen to your podcast.

- Thank you so much. - Like when I turn into your podcast, I'm going to embarrass you a little bit more by complimenting you a little bit more, but not out of a sadistic thing. But just because when I tune into your podcast or Joe's podcast, I have the same sensation that other people have.

Like, I feel like I'm home of sorts. I'm like, I'm familiar with the space and I'd like people to feel comfortable in the space that is the Hubert and Lab Podcast, whatever that ends up being. - Yeah, that's the magic of podcasting. It's like, I feel like I'm part of your life now in a way that as a fan, that I wouldn't be otherwise.

And, you know, like I never was able to have that with Carl Sagan, for example, you know? And that's a whole nother level of connection with a human being that gets you excited. And then I share your excitement about different topics in neuroscience or just biology in general. And then I don't have to actually understand everything you're saying to really enjoy it.

So that's the magic of podcasting is like, you can go through like 10 minutes and understanding what the hell a person is saying. And then you enjoy the excitement and then you reconnect to a thing that you do understand what they're saying. And, you know, that personal coupled with the scientific rigor is magic.

And finding the right, it's exploration. Like Joe found something that works for comedians, which is like, you know, having a good laugh, but also every once in a while, talking seriously about difficult topics. The scientific space, it was unclear. You haven't had guests on yet. But- - Maybe you'll come on as our first guest.

- I was gonna invite my, I was gonna try to force myself in there. - I am officially inviting you now. Will you come on the podcast as a guest? - I would love to. - Fantastic. - But it was hard. It's still a little bit difficult to tell people that, no, you don't get it.

We're not gonna talk for 10 minutes. We're gonna talk for three or four hours. It's a different, for scientists, for like, they're like, what are we gonna talk about? - I think it's like the NPR interview. - Yes. And they don't realize, first of all, I think at his best, if you're like at the level of Joe Rogan, who I think is an excellent conversationalist, you just lose track of time.

It can be three, four, five hours and you lose track of time. I'm still not there. I find that it's still painful. Like the conversation is still challenging sometimes. You don't lose quite as much track of time. It's still an intellectual effort. And I think it might always be as it would be with you because you're talking about difficult topics, maybe that require more brain.

You're not just shooting the shit with like a Brian Redband or somebody like comedians or just joking. - What's like, remember those shows, like where those shows where someone would come out and like spin plates and they're running back and forth. Really good scientific discussion is like that. You have to be maintaining three or four different logical arguments and jumping back and forth.

It's occasionally get into like a real streak of linearity. But as we found today that typically there's three or four different things that we're bouncing back and forth from. And that requires a lot of updating of these, you know, four brain circuits. It's not a passive listening experience. But I like to think that the brain likes that.

- I do want to ask just 'cause we all, I don't want to forget the question came up to me, is your podcast has the same kind of rigor that I think like a Dan Carlin podcast has who's a history podcaster. - Well, that's definitely a compliment. Thank you.

Dan's way, you know, he's something for me to aspire to. - He goes through hell to prepare. He spends months preparing. It feels like you've had to really prepare for your podcast. - I definitely prepare hard. - How, is that, are you okay? - Yeah, I-- - I mean, how much effort does that take?

It feels like a conference presentation. - Yeah, so we record once a week and in the intervening time, I listen to many university level lectures. So NIH has a bank of lectures. I have some sources of recorded university seminars. I'm trying to find the points of intersection. So like for four episodes on sleep, it's not like I'm gonna just regurgitate a popular book or take one lecture and just, you know, poach the content.

I'm gonna find the overlap in the different elements. I also, so what I'll do is I'll generally read 10 or 15 different papers. And generally those are good reviews, annual reviews, interview of neuroscience, annual review of physiology, those kinds of things. I'll chase a few references. I'll listen to some YouTube videos, but of university level lectures.

And then I throw all that on a whiteboard, usually while I work out in the morning. I'll just be working out. I have a gym in my house and I'll just put up all these random ideas. I want to cover that, dreams, hallucination. And then I take that and I start eliminating, I draw lines between the common points of intersection.

And then from that, I distill out an outline. And then I basically think about what I want to say on my walks with my dog. And I bother a couple of people and blab to them. So I would say each podcast, yeah, I put in 10 to 15 hours at least of passive listening preparation and maybe five or six of active preparation.

So I do prepare quite a lot, but it has a certain reward component for me. To come up at the end with something that's somewhat crystallized for me is just so satisfying. It feel like there's something about my dopamine circuits that just love that. And the only pain is that a year later, after I've talked about this stuff a bunch of times, it's so much more succinct, but that's life.

At some point, you gotta pull the trigger. - Well, I don't know what you think, but for me, YouTube is, that's why I'm sad that Joe left YouTube. There's a archival nature to YouTube that's kind of magical. And so I'm really glad you're now, you were doing a lot of educational content on Instagram before, but now doing this podcast thing on YouTube, it's like Feynman lectures.

I'm not saying every podcast, but there will be, you will have some, I can already tell, there'll be some lectures which are definitive, really special ones. - That's the hope. - And there's some aspect that's archival to YouTube where, at least I hope, 20 years from now, some kid is gonna watch a lecture of yours and it'll create the next Nobel Prize.

It'll create another dream that then becomes a reality. And that's a special thing that YouTube provides. So I'm really excited that you're on YouTube. And at the same time, I'm excited to see where this thing goes because it seems like change is the cliched thing, that change is the only constant in these times because you're paving with this podcast, with this creativity, what you were doing on Instagram as well, you're paving the new era of what it means to do science.

So actively doing research and actively explaining that research in new media. It's very interesting. - I'm inspired, genuinely inspired by you. We had this discussion last time after the podcast recording, and it's clear that communication of science cannot be left to the existing institutions. And I'm not talking about universities, I just mean that the science section of newspapers is, sometimes there's some gems there, but generally it goes, you know, and I think you really have to know a field in order to extract the best things from that field.

And my hope is that other practicing scientists and people finishing their PhD and postdoc and people who are running labs or working at companies will start to do this. I mean, how amazing would it be, for instance, if someone at Neuralink was giving us hints about not necessarily what they're developing, 'cause that's complicated for all sorts of reasons, but would talk to us about what the real challenges of building futuristic brain machine interface are like and what it means to understand a clinical problem and address it.

I mean, my hope is somebody there might eventually do that, that somebody in the world of chemistry or synthetic materials or whatever it is will do this in a way that I could understand 'cause I don't have expertise in those. I think it would be marvelous. And you were tip of the spear, you were out first, and I'm just happily trying to move along in the direction I'm going.

But I think the future of science education is online. And I think that's gonna be scary to a lot of existing institutions, but it's not about disrupting anything. It's just about trying to do things better. - Yeah, you know, some of the best interviews, some of the best investigative journalism is done by people inside the field.

Comes to mind a guy by the name of Elon Musk, who I love the possibility that he gets a Pulitzer for that interview, but he grilled the crap out of Vlad, the CEO of Robinhood, I'm not sure if you remember. - Oh, on-- - Clubhouse. - On Clubhouse the other night.

Yeah, I saw you guys in there. I was kept out, I wasn't quick enough. My thumb's doesn't go fast enough, so I was, and I wasn't about to sit in the waiting room. - Have you tried that social network, by the way, the Clubhouse? - I've gone in there a few times and checked some things out.

I'm there, I have a few questions about it that like if I'm in there, how one can participate or not participate. I like being a fly on the wall for those conversations. I've been very curious as to what's going on in there. - Oh, it's quite, I mean, I have a lot of thoughts.

Maybe it's useful to comment. I also have a Discord server that has a few tens of thousands of people on it, and then they have also a voice chat capability. So they have these get togethers. And I was using it in the spring and summer, like actively on those voice discussions, and it's anywhere from 10 to like 1,000 people all together in voice.

Like anyone can speak anytime, right? But there's this weird dynamic that people stay quiet and only one person speaks at a time 'cause they're all like respectful. And it's a community of like fundamentally respectful people, even though they're all anonymous. So like, except like me and a few others, it's all anonymous people.

- So interesting. - And it works. But the magical thing to me about that community was how intimate voice only communication can be. It felt as intimate as like a small get together at a home with close friends. It felt like there's a calmness to it, and you're revealing things about, you know, somebody suffering from depression or being suicidal.

So those are the dark things, or being super excited getting a new girlfriend or boyfriend. Like just the depth of human experience shared on voice without video is, I was really surprised how intimate that is for human connection, especially in this time of COVID, it replaced that. So that, so just to give you some context, there's something there.

- There's definitely something there. One thing that comes to mind is when like in Clubhouse, you have your little icon, so they don't actually, you don't see your face moving. I think when people see their own image, it puts them in a state of self-consciousness that is eliminated by just having an icon or an avatar.

- Yes. - So like Zoom is dreadful, because if I'm not used to talking to people and seeing a little image of myself staring back at me in a mirror, and it's just, I know there are ways that you can adjust that, but it's really awful. And I think that when I get on Zooms now, I say hello, and then I shut down the video component, and then I just talk in the end, I come back on just to show that still there, it's still me.

But I think that voice only is really interesting. Eddie Chang would be an interesting person to talk to about this, because he understands so much about how inflection communicates emotionality and deeper state. - But there's a balance between, I think just like you said, the privacy somehow allows for the intimacy.

So like being able to, as opposed to putting on an act, which I realize we do when we're visually presenting ourselves in remote communication. But I think that there's so few places where people can actually communicate without the fear of penalty. - Yes. - That's woefully absent these days.

And so maybe people are just relieved to be in a place where they feel like, I can say what I want or not say anything, and it's okay. - And so Clubhouse, to answer your kind of question, is it was a big improvement to me over Discord, which is it has tiers.

It has a stage where people, the person that created the room can invite people up that would like to speak potentially, have the opportunity to speak. And then there's a bigger audience that don't get a chance to speak unless they click raise their hand and they get called on.

So there's like a tier system that allows for there to be a group of like five, 10, 20, 30 people talking and a lot larger amount in the audience, which in Discord was a problem was that everybody could talk. And the other thing about Clubhouse is everybody is strongly encouraged to represent themselves.

So you're using your real name. It's not anonymous. - How many people were in that GameStop discussion the other day? - They currently limit rooms to 5,000. So I'm sure maxed out at 5,000. There's a lot of overflow rooms. This is the cool thing about Clubhouse, really big people were on there all tuned in and having a conversation, having all from all these different worlds, being able to connect, even though without the niceties of like arranging the meeting, you could just show up and leave, which is nice.

But the reason for my lessons from Discord, I'm going to mostly stay away from Clubhouse. And I think-- - Or go in there under another name. - Right. - I'll pretend I know your actual name on Clubhouse. - Yeah. (laughing) I've learned it's quite addicting. It's a time sink.

It's so, the intimacy of it is, you find yourself wasting quite a bit of time on there. It pulls you in. - Well, it's interesting. The, in sort of going back to the podcast or earlier we're talking about books or creating a technology. One thing that's absolutely clear is that anything that's easy to reproduce is probably not worth much effort and time.

- Yes. - Right? Most posts could be easily reproduced. You just repost them. - Yeah. - So now there are some original posts that for which the attribution goes to the original person. It's clear it came from you. But anything that can be easily reproduced is doesn't really expand us very much as individuals or as groups.

And most of what I see on social media is stuff that is purely reproduced. - Yes. - But I think Clubhouse, I mean, it could be that some real magic emerges on there. - So in moderation, it could be good. The magic is, this is another thing that I've found through COVID that maybe you can think about is live.

I used to be, not understand the appeal of live video or live connection or like in this Clubhouse live events because Clubhouse is technically for the most part, it's not supposed to be recorded. Most people don't record most conversations. It's a one-time live event. And there's a magic to that.

- There is. - That's not captured by a, like your podcast or my podcast produced video that's like recorded, like packaged up. - Well, anything can happen. It's that anything can happen. And that's the kind of thing like live concerts. I definitely, I love live music. And it's the idea that, 'cause you can always listen to the album.

Actually, the album usually sounds cleaner and better, but it's just this idea that anything can happen. - And then you listen to like the parts, I don't know, you like Costello did something weird, your dog did something weird. And then you have to go, God damn it. You have to go to the kitchen or something to get something and then you come back.

And it's funny, I watched live video like that of people and I'll be there for the whole time. I'll wait for them to go to the kitchen and come back. It's not like I tune out. And that makes it like a richer experience for some reason. It's weird. - Well, it humanizes it.

- Yeah, humanizes it. - And I think there is this weird effect of whether or not it's a podcast, Instagram, or Twitter or anything else. There's kind of like two people shouting into a tunnel and then a bunch of people with ears at the other end of those tunnels and shouting some things back.

You know, that's kind of the format we're in. I think, I'll check out Clubhouse again. I've gone in there a few times during the day and I was surprised to see how many people were in there in the middle of the day. I was like, "Aren't these people supposed to be working?" But maybe that is their work.

- Well, be very careful about the time sink of it. But yeah, if you wanna, you and I go together, we'll have a conversation on there. But one of the things you have to figure out, I don't still know how to do it, but how to exit. - Which is you just do that.

Isn't there the leave quietly button? - Yeah, no, but like when you and I are on stage having a conversation. Like, okay, you and I is harder, but like you really, if it's just you and I, then it's the usual human communication of like, "All right, I gotta go." Like, but when it's like four people, you don't wanna interrupt everyone and ask you're leaving.

You just have to, I mean, there's a weird dynamic that I haven't quite figured out of-- - The etiquette isn't clear. - The etiquette is not clear. - Well, the etiquette on different platforms and how that changes is really interesting. You know, how YouTube has one etiquette, which is kind of, a lot of harshness is tolerated on YouTube video comments.

Twitter seems a bit harsher than Instagram. Instagram, there's kind of, it seems to be a little-- - People are nice. - People are really nice. People are really nice on Instagram for the most part, except for those phishing things. I actually know someone who had their quite sizable account poached by those copyright.

They come in with those like, you violated copyright thing. There's all sorts of harshness in there that if you think about it in the real world, I like to think about Instagram as if it was the real world. Someone comes over and is basically saying like, "Hey, can I hold your wallet and go into the bank and I'll get some money out for you?" But there's this trust based on the format it comes in that it can almost get past your radar unless you're suspicious.

If you took comments, like, you know, your posts get a lot of comments and you just walk past 500 random people on the street and just listen to what they say, it's like, that's ridiculous. I don't have time for that. But the comments somehow take on this importance and this relevance and we feel obligated to give them value, right?

And so the online communities, the rules really are different. - And they evolve with time, which is fascinating. With Clubhouse, it's a new social network, so it's evolving and people are figuring out as you go. And the same thing with podcasting on video and like scientific podcasting. This is the cool thing when I look at what you've created, I'm learning, I'm thinking like, hmm, that's interesting to do it this way.

'Cause like, I have nobody to copy. Not many people to copy, you know what I mean? - But you threw out an idea, I'm not gonna put it out here now 'cause I don't wanna, 'cause knowing you, you'll hold yourself to it no matter what. But when we talked about this issue of the challenge of staying on a particular topic for a while, I mean, you do have some cool stuff brewing in there.

- Oh, no, no. - That's separate from this format. And I love your interview format, but when you told me about that, I got really excited that you might go forward. I'm not gonna tell your audience what it is, but I will say this, it is super cool. I would have never thought about it.

It's distinctly different than what I'm doing or what Lex is currently doing. And if you decide to do that podcast, I will be your first and your number one fan. And I know there are gonna be millions of other people interested in that. It would be amazing. So if you decide to go forward with the idea, that would be awesome.

- I was gonna say what it is, but now I'm not going to because that's even more interesting. I brought up the clubhouse thing actually in Elon because I just wanted to get your thoughts about something he's said a few times to me and to me in general, is that he's under a huge amount of stress.

And I'm thinking of doing a startup now and kind of thinking about all of this. 'Cause I enjoy podcasts, I enjoy science, but he says that his life is basically hell. It's very difficult. - He looks happy, but he's probably very good at math. - He's fulfilled, he's fulfilled.

But the stress levels, the constant fires that he has to put out. And he says that most people wouldn't wanna be me. And that basically the reason he does what he does is because there's probably something wrong with him. He can't help it, but do that. - It's kind of beautiful.

In a kind of Russian masochistic way. - Well, I just wonder the stress. I mean, I'm sure you can imagine the kind of stress he's under because it's running three plus companies and there's constant, he says that every single meeting is not about like should we install a coffee maker in the kitchen?

It's like, this rocket is going to blow up and we're all fucked, I don't know what to do. And you have to fix-- - Real problems. - Real, big problems that are, and how do you deal with that? What do you think about that kind of life? One, is there a way to walk through that fire?

And two, should you walk through that fire? - Well, I mean, without knowing, I've never met Elon, but certainly we have common friends in you and in other people that he worked with long ago, the PayPal days, all of whom speak very highly of him and express immense admiration for the number of things that he can maintain.

I think it's fair to say that he accomplishes more before 9 a.m. than most people do in a decade, it's clear. And that what he does would dissolve most people into a puddle of tears, mostly because of this whole thing about the brain working hard equates to thinking about duration, path, and outcome and anticipating outcomes given A, B, C, or D, a lot of very scripted linear thinking.

And prediction, and that is hard, it's stressful, it requires intense neurochemical output. And he's doing that for multiple projects. So presumably he's buffered himself from the coffee maker issues and the little tiny issues, but he is himself, unless there's something I don't know, he's walking around in a biological system.

That's- - Allegedly, yes. - Yeah, allegedly. So, and I don't want to reveal too much here, but I have a common co-worker and colleague through some contract work I do, that what I can tell you is that he's accessing the best resources in terms of how to optimize his biology.

And he's thinking about that, not just for himself, but for all of Neuralink. Because I think, I'm not trying to dodge the question, but I think there's the scale of the individual, but then there's the companies that he's creating. And you've got people there that you could imagine if they're working at 10% better capacity or can focus 5% better for 20% of the day, you're looking at an enormous increase in productivity and a reduction in the time to reach goals, which will reduce the amount of stress, presumably on Elon, unless he goes and starts another endeavor.

Right, so I think it's certainly not healthy for most people. It seems to be where he gets his dopamine hits. I'm also really struck by the fact that he has a family and he's got kids growing up and a relationship and all that. So it's super impressive. I think that, I don't know, how old is Elon?

- He's 40, I mean, pushing 50, I think 48. - Even more impressive. - 49. - Because many people who've been at exceedingly high output for a decade or more don't do well. Their system breaks down. - Well, this is what he was saying. Actually, I mean, I don't listen to all of his interviews, but on that live on the Clubhouse, he mentioned that he was kind of worried.

It's interesting. He was worried that sometimes, what I think he said is, "I'm worried that at some point my brain "is just going to fail "because of the amount of load it's under. "Like how much I have to think through throughout the day. "Like how many problems you have to think through." Like, you know, it's like puzzles.

It's constant puzzle solving. - I would be concerned about taking somebody who's in that regime and suddenly putting them into a regime where they don't have enough to bite down into. It's like my bulldog Costello. He's happiest when chewing and tugging with that big old neck of his. And he is just not going to become a retriever.

He's not going to, that he does well and gets his dopamine hits from chewing and pulling. And it seems like Elon has ended up where he is by way of his natural leanings. Unless there's a backstory that's trauma-based or something, and I don't even begin to think that there is, it seems that he has, he's one of those rare individuals in history that has an immense drive to create in all these different domains.

I'm just saying the obvious here. But it seems like that's what makes him tick. I mean, you're doing an awful lot too. - Well, the problem is not really, the problem is I'm about, I've been on the verge of pulling the trigger on starting a company which will increase the workload significantly.

And I'm attracted to that because of a dream I have, but it's a little bit scary because it can destroy you. In a lot of ways, there's two sources of destruction. So one source is, I've, for the first time in my life, a few months ago, I think, have gotten, this feels like such a noob thing to say, but I've gotten some hate on the internet.

- No. - I know, right? - No. - But I'm such an idiot, I'm so naive to, it was, I had the question that I guess a lot of people have when they get hate on the internet. It's like, "Mom, why are these people "making up stuff about me?" That kind of feeling of like, "Why are you saying that?" And the reason I mention that is like, well, if you wanna go and start a business and do as I think people should when they start a big, ambitious business, really try to go big.

What does success look like in terms of your emotional journey? You're going to have a lot of people who make up stuff about you, who say negative things. I mean, majority, hopefully, if you do a good job, will be supportive, but there's still going to be this army of people.

And that was scary to me because of how much emotional impact that had on me. - Well, and I also know a little bit, I have some glimpse into the fact that you put your heart and soul into everything you do. You're not a, you're lighthearted about certain things, but you're even lighthearted about being full gas pedal 24/7.

There's kind of this, was it, was it Laird Hamilton always says, the big wave surfer, he always says, "Bright light, dark shadow." And I think it's that intensity. And when you do that, and then suddenly people are starting to throw some paint on your picture. You're like, "Wait, hold up." You're going max capacity.

But I think the company is an interesting one because you've talked about doing this company before. - I've been afraid. I've just not been pulling the trigger out of fear 'cause I enjoy this life. This is, and sorry to interrupt, but it's ultimately this question of taking a leap.

It's like, say you're in academia, like you're at MIT. I really love doing research at MIT. I really love that life. Why take a leap out? But I did because it's been a dream. But now accidentally along the way, I found this podcasting thing, which is also really fulfilling.

And it's like, why take a leap? - 'Cause you have a huge lust for life. - Yeah. - I mean, sometimes when I'm on the internet and I think, you hear about it, like, "Oh, it's addicting. YouTube's addicting." Actually, sometimes I think maybe that's true. But a lot of times I just think there's so much here.

There's a lot of garbage, but there's so many gems out there in the world now. It's almost like, sure, how you allocate time is key, but I think you can do it all. Not maybe not five more things, but all. - And one thing, I just had this idea, and this is not grounded in any scientific paper, but I think the answer might come to you during this torture that you're about to put yourself through with David.

Because in those mental states, you're really asking the question, right? You're asking the question, where is my capacity? And am I even close to my capacity? And if I am, what's of the most value? I think we find the answers to those things in those nonverbal, nonanalytic states. It just comes to us.

- I hope you're right, and I hope it's a profoundly fulfilling experience as opposed to one that leads to my demise. But-- - You have a will, right? (laughing) It all goes to the hedgehog. - Yeah, exactly, to the hedgehog. Now it all makes sense. Andrew, like we talked about offline on this podcast, I do hope we write some stuff together, do some research together.

You're one of the most inspiring scientists speaking and communicating to the world. So I can't wait to see what you do with the podcast. I'm already a huge fan. I've been telling everybody about it. I can't wait to see you talk to Joe as well soon. And I can't wait to see what kind of paper we write together.

Thanks so much for talking to me. - Thank you, that project's gonna be a lot of fun. Can't wait. And thanks again for having me on. Appreciate you, brother. - Thanks for listening to this conversation with Andrew Huberman, and thank you to our sponsors, Masterclass Online Courses, Four Sigmatic Mushroom Coffee, Magic Spoon Low Carb Cereal, and BetterHelp Online Therapy.

Click the sponsor links to get a discount. And remember, now is the time to sign up to Masterclass if that's something you've been on the fence about. And now, let me leave you with some words from Woodrow Wilson. "We should not only use the brains we have, "but all that we can borrow." Thank you for listening, and hope to see you next time.

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