REM neurochemistry: acetylcholine ↑, norepinephrine ↓

16:08noise of all of the brain sort of like getting really activated. >> So we're sort of seeing there's like a the chemistry balance of what's happening in the brain >> changes in between waking and sleeping state with this acetylcholine and uh what was the second one? It was >> norepinephrine. >> Norepinephrine. >> Yeah. >> The norepinephrine is the is the the guards. Yeah. That's the guardrails. the guardrails and the acetylcholine is what allows you to kind of explore a little bit more crazy. >> Yeah. And because that balances off during REM sleep, >> that's then it's like, well, what's over here? >> Yeah. Very interesting. >> Oh, I'm flying. Oh, that's a monster. Like [laughter] crazy stuff >> and during your dreams. >> And it tracks because it makes sense for anyone who's had vivid dreams before,

16:49right? This idea that um >> you know, they do kind of exist in this weird realm a little bit beyond what is realistic. >> Yeah. >> But still feel grounded in realism to Yeah, because it's like synthesizing all the memories that you previously have, but now it's just on overdrive. It's like trying to connect all this other kind of stuff. >> Makes total sense. >> It's it's it's it's pretty cool that we can go all the way down to the biochemistry level. >> Yeah. >> And like still see the subjective effects all the way up. I >> I neuroscience is like crazy and there's just so much more that we don't know about the brain, right? And the fact that we're getting this far is already I think really really cool. M so now let's talk a little bit about information

17:30theory >> and the brain okay because the brain is an information chugging machine >> there's this idea of entropy which is the same kind of idea that we have in uh physics the idea of randomness how structured is the data in our brain >> if we look at the ECG signals >> which is the signal the electrical signal that we would get if we were to put electrodes on our scalp right >> you can see that the wakefulness and the REM sleep look very very similar. This is what I was alluding to before. Slowwave sleep, which is deep sleep, that's the part where we're not dreaming. That's like super deep. Nothing. There's no subjective

18:11experience so far as we can tell of that. And light sleep are look very different compared to REM and wakefulness. REM is almost like we are wakeful >> but our body is completely paralyzed. And the way that our body does that is our brain, our brain stem, which is the part that connects our brain to the spinal cord, completely blocks all the signal. >> Oh, okay. >> Okay. That's why we don't act out our dreams. Well, I mean, some people do, and they've got a they've got a little >> We're acting out our dreams right now. [laughter] >> I I think we are actually on this show. We've talked about this for a very long time. >> Yeah. But you know what I mean, right?

18:52like when we're dreaming and like we're doing all the crazy stuff, our brain stem is actually paralyzing the rest of our body. >> Okay. But the dream state itself looks very much >> like the wakeful state. That's something that I >> really want you to like imagine. And I think that's kind of crazy to think about. >> Yeah, it is. >> That like during dreaming the brain is basically simulating reality, >> right, >> of being awake. It's just we're not acting it out because the brain stem, which is the part in the back of our brain connecting our spinal cord to the brain, is just like, "No, none of that signal is getting through." >> It's it's sort of like the brain is putting on a biological VR headset, utilizing your memory as the context by

19:34which it then projects imagery into your like mind's eye uh while paralyzing your body movement. So, you don't have to worry about running into your TV. >> Yeah, [laughter] dude. That's exactly right. That's I mean, it's exactly what it's doing. It's like a little VR. >> Yeah. >> That's that's in our head that we're making up as we go along. So given all this given all these constraints, right? >> Yes. >> Now let's talk about how do we do sleep engineering, >> right? Cuz now we've set the basis of why we can actually look at dreaming uh from a quantitative perspective >> and understand the numbers. Yes. >> And see it. Yeah. >> And track it. >> Yeah. But now the question is how can we

20:16actually be more targeted not just read how do we read and write? >> Yes. Yes. How do we now how do we now write >> into the sleep itself? Right. We want a deliberate manipulation of our sleep >> content. Right. And it's funny because in the waking state we have a variety of things that manipulate our conscious waking experience. >> Yeah. >> So theoretic I mean just like loosely speaking >> Yeah. If there's such a matchy matchy, >> yeah, then it should be possible, right?