Does ten seconds in a dream equal ten seconds in real life? How do you get information to somebody when they're in a dream and how can they answer you back while they're inside their dream. Why might you see someone in real life flicking the light switch on and off every time they enter a room? Can you prompt your brain the way you prompt a large language model like chatchpt And if so, if you could pose one question to your unconscious brain, what would it be. Welcome
to Inner Cosmos with me, David Eagleman. I'm a neuroscientist and an author at Stanford and in these episodes we sail deeply into our three pound universe to understand why and how our lives look the way they do. Today's episode takes us on a journey into the world of lucid dreaming. What is that? How can you experience it? And what does it teach us about the nature of our own consciousness. Joining us in a little bit will be my friend and colleague Jonathan Barrant, who is very
knowledgeable about the art and science of lucid dreaming. So get comfortable and let's dive in. So maybe you saw this great movie Inception In case you didn't or as a reminder, this is a Christopher Nolan science fiction heist thriller.
The star is Leonardo DiCaprio, and he's a skilled thief who specializes in extraction, which is this fictional process of entering a person's dream and stealing valuable secrets from deep within their subconscious Now, the core of the story revolved around this idea of inception, which is the idea of
planting an idea into somebody's subconscious mind without them knowing. So, without giving away any details, DiCaprio sets out to incept an idea into a business magnate's dream and this is a really complex operation that requires his team to navigate through dreams within dreams within dreams. And I won't give away any spoilers here, but one of the very cinematically cool ideas of the movie is that each layer of
dreams has successive time dilation. So when you go down into the first level, ten seconds in the real world might correspond to a minute of dream time, and as you go deeper, the ten seconds might correspond to a year or a decade of dream time. So the idea in the movie is that dream time does not correspond to real time. Now. It's a terrific movie, and if you haven't seen it, you should. But there's this question which lots of people have wondered about, which is, how
would you know if that's true? How would you know whether dream time matches real time or not? Now you might feel like they don't correspond. And this is in part because sometimes you wake up from a dream and you want to tell someone about it, but the telling of the dream often seems to take a long time,
even if the dream only took you a second. And in the last episode, I touched on why this can be confusing because sometimes you have to explain a bunch of background details, and sometimes you have false memories in the dream that need to be included, and so it sometimes takes time to get the whole thing put into words. So it can be difficult to answer whether dream time and real time correspond. But today we're going to go one step deeper. We're going to ask is there a
way that you could actually test this? Now, think about what a difficult question this is, because it would require somebody to be inside of their dream, and somehow they would need to communicate with you what they are experiencing.
Privately in their head. Now that sounds totally impossible under normal circumstances, But the question is, could you ever be inside a dream and figure out how to communicate outside of the dream, Or even better, could we think of a way to get bi directional communications so that someone outside can communicate with you in your dream and then you communicate back out to them. Well, it turns out there is a way to do that, and that's what
we're going to talk about today. We're going to talk about lucid dreaming, and this is when a sleeper realizes that he or she is dreaming and then is able to take some control over the plot of their dream. They might choose to fly, or they can try to control other people's actions, or generally just manipulate the physical world of the dream. So here's my analogy. You know those kids rides at the amusement park where you're sitting in a car and you can steer the wheel, but
the wheel doesn't actually do anything. You're just on a track and the car just follows wherever the track goes. So imagine if you could get the steering wheel to work and actually steer off that track. That's what a lucid dream is instead of you always being the follower in your dream, you are now the driver. Now, to many people, lucid dreaming might sound like a concept straight out of science fiction, but it's a well documented state
of sleep. A dreamer can become aware that they are dreaming, and this awareness can from a faint recognition of the dream state to a more profound acuity where the dreamer takes control over their own actions and manipulates their environment. Now, to understand this, we need to remember what we talked about in the last two episodes, which is that our
sleep during the night moves through various phases. One of these is called the rapid eye movement stage of sleep, or REM sleep, and this is where our vivid dreams occur, and it's during REM sleep that lucid dreaming is most likely to take place. Now, I mentioned last week that during REM sleep, our body's major muscles are paralyzed, which prevents us from acting out our dreams, and this is
also true during a lucid dream. But certain other parts of the brain, especially those involved in self awareness and executive function. These become more active when you're having a lucid dream, so we usually think of brains as having two possible states. You're either awake or you're asleep, but being in a lucid dream is somewhere in between, and the brainwave activity measured by EEG is different from normal
rem sleep. So this makes lucid dreaming a unique state of consciousness where the dreaming mind wakes up but the body remains in the sleep state. So the first question is how do you do this? How do you become lucid in a dream? Sometimes, if you're very lucky, a lucid dream will happen. Accidentally. I had won many years ago when I was in a dream where I was at my high school locker bay with all my classmates, and it slowly dawned on me that I was in a dream and that none of this was real, and
I was able to take control of my dream. But it only lasted a few seconds before I woke up up. But lucid dream efficionados can train themselves in a variety of ways that we'll talk about to have lucidity more often and for longer. The main technique involves setting an intention just before going to sleep to look for signs that you're dreaming. Little clues that something doesn't quite make sense, and then the idea is if you see those things that will alert you that you are inside a dream,
and then you can try to take control. The general story is that if we get good enough at questioning reality, we can then pass more easily into lucid dreaming. So what is lucid dreaming all about? And how can you get good at it? To explore this in depth, I called up my friend Jonathan Barrent JB. As he goes by. He worked for many years at Google, including at X the Moonshot Factory, and he is a connoisseur of lucid
dreaming and he lectures at Stanford about it. So I wanted to get his take on this rare and amazing version of consciousness. So, Jonathan, what is a lucid dream?
A lucid dream is any dream we're actually aware that you are dreaming.
What got you interested in lucid dreaming?
There was a book called The Shaping Room, and it was a fictional book, but the character in it had the ability to imagine these landscapes. He would actually put his hand in this clay and I just got curious, and I think, you know, one day in a bookstore, I came across Stephen Laberge's exploring the world of lucid dreaming, and I read that and I realized, like, wow, there's actually a way to get into a state of consciousness where you can envision different dreamscapes and you can have
some measure of control. And I was hooked ever since.
And for anyone who doesn't know, Stephen Laberge is a colleague of ours who is a century the pioneer in lucid dreaming. And so the question is, JB, what are the best ways that somebody can train up to allow themselves to have a lucid dream. Sure, there's a few key steps. The first one is working on dream recall. You want to get to a place where you can remember two, three, maybe even four dreams a night. So you know, having a dream journal, having the intention to
remember your dreams is you know, the first key. As you build your dream journal, you're going to find what are sometimes called dream signs. You'll find that there are some certain patterns, like for me, if a dream sign is being back in Indiana, where I was from. And so as you start to learn your dream signs, you can then start to anchor on that being something that triggers lucidity. If I can just clarify for the listeners, a dream sign meaning a sign that you are dreaming exactly.
Yes, you're looking for these sign posts because we don't naturally question reality right now, we're not even questioning that this might be a dream. But we because we are often fooled in most of the dreams we have, we don't have that recognition. So you need cues, and we call those dream signs. And the more you journal about your dreams, the more you'll find some patterns. So that's the first step, is you have your dream journaling and you have your dream signs.
So that you can get good at recognizing I am I must be in a dream right now?
Correct. Now. There are some ways that have been really scientifically studied and rather robustly to ensure you have sort of a maximum chance. And so one of those is the mnemonic induction of lucid dreams. And so that means, as you are going to bed, you can say, next time I'm dreaming, I want to remember that I'm dreaming. You sort of place this little hook and they call that prospective memory where you're trying to remember something in
the future. Now, you can make it even easier on yourself if you wake yourself up after about three or four hours of sleep, and that method is called the wake back to bed. Why, well, you get through most of the denser part of your sleep at the first part of your night, the slow wave sleep, the restorative sleep, and then the latter half is more rem sleep. So if you wake yourself up after three or four hours and then you do that mnemonic induction of lucid dreaming, say,
next time I'm dreaming, I want to remember I'm dreaming. Well, you chances are you'll go directly into REM. And when you go directly into REM after having slept for four hours and maybe being up for a little bit, you're going to be more likely to actually see that trigger and remember it that you're actually in a lucid dream. That's one of the most effective ways to become a lucid dreamer.
Let me just understand it. It's what do you mean I want to remember that I'm dreaming? You mean I want to recognize that I'm dreaming. Yes, okay, yes, So you're in a dream and you say, wait a minute, I'm back in Indiana. This doesn't seem real, I must be in a dream. And so then what do you do.
When you recognize or you think you recognize, it's good to do what's called a reality check. You want to see are you truly in a dream state? And so there's been lots of different reality checks along the way. Some people look at their hand. That was popularized by Carlos Cassandra and his books on the Pathways of Dreaming.
Why look at your hand? What are you looking for?
Well, when you look at your hand in a dream, it just doesn't look like a five fingered hand. Often there'll be like a sixth finger. It will it will have some sort of blurring, you know, to it for some reason. Although the mind can recreate many, many things with exquisite detail and dreams, it has trouble recreating a perfect hand.
This sounds like Dolly, yeah. So the idea is you get in the habit of looking at your hand and if it looks odd, then you say, why does my hand look so odd? And then you think, wait, wait, I must be dreaming.
That's the idea, right, that's right, that's the idea. Other people might try to fly. Obviously, you jump up and gravity holds you down, then you know you're most likely in this reality, which lucid dreamers like to call consensus reality. And you know, there's another one that's kind of interesting that if you pinch your nose and try to breathe, which I wasn't able to do, but in a dream, there's no constriction and you actually will breathe right through that.
So that's kind of an unusual reality check. There's many of them, but the main thing is to have one or two reality checks that you can do both during the day at a time like this, and then when you are you know, have some sort of recognition that you're in a dream, you can perform that reality check and then it'll either pass or fail.
So the idea is to get in the habit of doing reality checks, like seeing if you can breathe with your nose pinched, or whether you can see your hand. Another one that I'm fond of is you put your you know, your thumbnail up on your tooth and you try to flick your tooth off, and in consensus re reality, your tooth doesn't come off. But often what will happen in a dream is your tooth goes flying off into the air and you think, what the heck just happened? You think, oh, yes, I must be in a dream.
That's right. All those are better than what has been popularized in the movie Inception, which is the spinning top. Of course that makes for a good graphic and a good movie, but that's not really a great reality check. Any of these other ones that we've talked about are much better.
Wait, I had forgotten about the spinning top. Why what were they doing? And why is that not a good check?
So you know, Leonardo's character spins it, and if it falls down, then he knows he's in a that he's in consensus reality. But if it keeps on spinning, then he's in a dream. And of course the movie ends with this you know, undefined state of like who knows if this whole movie was a dream, But you know, in an actual dream, you know, when you're spinning, there's no evidence that the top will keep on spinning in
a lucid dream versus you know, fall down. Much more tried and true methods are the ones that we've talked about. The only other one that gets, you know, a little bit closer to something like that is a light switch. For some reason, when you flip light switches in lucid dreams,
they tend not to work. But the by far the most robust one that with the science behind it, is one that we haven't mentioned, So that one is looking at a piece of text, so something that's been written, and that could be you know, could you know, be your watch? You know, twelve thirty nine. You look away and then you look back, and indeed it's the same.
And so Leberg's i think, was the first to study that and found about eighty to eighty five percent of the time that was a reliable measure that the brain doesn't recreate.
You say, it's the same in consensus reality, but in a dream when you look back at the clock, it is different.
It's different, yes, And that's because there's no sensory constraints in the dream, right. And so I think one of the one of the interesting things that Lebert's used to say, and he was, you know, my mentor for years, and I'm very grateful for all the things that I learned from him. He said that dreaming is really perceiving without
sensory constraints, and perceiving is dreaming with sensory constraints. It's a little bit of a play on words, but it's really getting across a fairly important piece of meaning that the dreaming mechanism and the perceiving mechanisms are very very similar.
So let's unpack that for the listeners. So the idea is that, you know, you just take vision, for example, only five percent of the input to the visual cortex is actually coming from the retinas, from the eyeballs, and
all the rest is internally generated. And so this is why you can have dreams, for example, where your eyes are closed but you're having full, rich, visual experience, because it's just this machinery running on its own without the little bit of modulation that comes in from your eyes. And so this is the sense in which when we're awake it's like awake dreaming. It's the same processes that we have when we're seeing when we're dreaming, it's just that when your eyes are open, things are anchored a
bit more. I'm just unpacking this. So this is what you mean when you say, actually, how do you phrase it?
Perception is Perception is dreaming with sensory constraints, and then you can you flip.
It so you're anchored to what's in front of you. But otherwise it's the same process as dreaming. Okay, now, what was the other half of the sentence?
Dreaming is perceiving without sensory constraints, got it, okay?
Right, in the sense that your brain is doing its thing, but it's not tied to what's actually on a wristwatch. It gets to invent what's on the watch at every moment.
Right now. One of the interesting studies that Stephen Labers did and then Philips Embardo also one of your colleagues at Stanford is they wanted to design experiment that could you know, actually prove this, and I think it's fascinating. It was published in twenty eighteen in Nature Communications. And as you're very well familiar, the eyes when they lock onto something like a finger and they trace it, they have a smooth pursuit.
So when you're hold on when you're moving your finger back and forth in front of you, just for listeners, your eyes are smoothly moving back and forth with your finger, as opposed to if you're not moving your finger and you just try to move your eyes to the left and right. Your eyes make jumps. They go jump jump, jump, jump, and then they go jump jump jump, the other way. Those are called secods scots.
Yes, So with that in mind and with you know that understanding of our neurobiology, they designed a clever experiment where they had participants look at their finger in consensus reality and then just trace a circle. And then they had leads eog leads to measure you know, their eye movements electro oculargram, so measuring the potentials of the eyes. The eyes are pulled rise, so when you move the eyes just very you know, basic biopotential sensors can see it.
So these are little electrodes you stick on to the outside of the eye and you can measure where the eye is located, whether it's looking up or down or left to right, even when the eyelids are closed.
Correct. Yes, And so they measured that while people were tracing their finger and doing a circle, and it had as you would expect, that smooth pursuit seeing you know, the eye tracings in that. Then they had people you know, close their eyes while still awake and just imagine that, and so you know they can move their eyes, but as you just said, they have more psychotic movements when there's no anchor, when there's no finger to anchor on.
So if I'm just imagining my finger moving with my eyes closed, I see jump jump, jump jump instead of smooth pursuit.
Okay, right, So then they had these people go into a lucid dream and remember the dream task of actually putting their finger up their dream finger and watching it go around and much too. I think the surprise of many, it mirrored much more closely. I could show you the plots in the paper much more closely to the waken reality and compared to the imagination where it was very jagged.
So the idea is, when you're an elucid dream and you're imagining your finger moving back and forth, your eyes are making something more like smooth pursuit because it's like actually seeing it.
Yes, yes, it's kind of amazing because then it goes back to what we were just saying that dreaming is perceiving without sensory constraints, and perceiving is dreaming, And so the mechanisms are very similar. I'm not saying that they're identical, but they are very similar, and I think that just opens up to a lot of interesting possibilities for lucid dream research.
Now we jumped straight into something which is doing an experiment with lucid dreaming. But I just want to fill out a little bit more so everyone gets this. So let's say I look at some texts in a book and the text doesn't really make sense, and I look back and the text is different. I might think, Wow, what's going on here? Oh wait, I must be dreaming, and then I can transition into making it a lucid dream. So what happens when I turn lucid?
Yeah, So when people turn lucid, they often, if it's the very first time, it might be a very short experience because they get kind of excited, and as they get excited, more areas of the brain light up and they wake up. However, if they don't, or if it's maybe their second or third time, they can then really explore the world. They can look at the objects around them, they can touch them, feel them, they can taste them. All five senses are working in the dream world. They
could travel to a different location. It's interesting to note that there's almost like skills that you can develop. It doesn't all just happen in your first lucid dream, but over time, you can do almost anything without the physical laws or the social laws of convention applying.
And so one of the things that you can do is follow the instructions of an experimenter who's told you when you fall asleep, I want you to look at your finger moving back and forth in your lucid dream. So they're actually doing something that they were told to do once they realize they are there.
That's correct. Yeah, remembering the dream task that in and of itself is a skill. It takes a while because you're so enamored with the lucid dream world and all the possibilities, but it can get to a place where you can remember, Hey, I had this intention, I'm supposed to do this because of an experiment that I'm doing. Or oh, I wanted to go to the Eiffel Tower and see, you know, what does it look like from the Eiffel Tower because I have a trip coming up
to Paris. I want to see if it compares all kinds of very interesting things. Both can be formal experiments or does self experiments great?
And now what allows the experiment to take place is that there's a way that you, as the lucid dreamer, can communicate with the outside world. And this idea of hooking up an electro ocular gram so you can see where the eyes are pointing. This is one way that you can talk with the outside world. So besides the thing of following your finger, what are some other examples where you can talk to the experimenter through your eye movements.
Sure, well, that was sort of the fundamental piece that Stephen, you know, contributed to the science this left right, left right signal. So it can and it's become the de facto uh signal that somebody is actually in a lucid state. So just unpack that a little bit. You know, sleep scientists they have characteristics that they look for that they can and say definitively somebody is asleep. You know. That's when you have an EEG hooked up to your scalp and the eye leads and often a chin lead to
measure the muscle movement. You can definitively say somebody is asleep and that they're in rim. And then when you see that sharp coordinated left right, left right, that is just a clear sign of the eyes that somebody is actually becoming lucid.
Specifically, the subject is told when you realize you are in a lucid dream, and why you look left and then right and left and then right.
That's correct, yes, And so that was established, you know, in the early eighties with part of his PhD work at Stanford and since then has been the gold standard. Now, if you think about that, though, what could you also do with that eye movement? You don't just have to signal lucidity. You could signal other things. You could actually pass information based on let's just say the number of
left right, left, right. And in fact, that was some of the you know, kind of co or thinking that went into a series of experiments that I participated in along with kin Power and Karen Conkly that are just fascinating that you know, we could we could talk about. But essentially we took it one step further where we wondered if you could get information into the dream, that the dreamer could receive that information, do something with it, and then communicate it back out.
Great, what's an example.
Okay, this may not be the most fun example, but we took math problems as just a very simple way to actually approve could we get information into a dream
such as what is six minus three? For example? And you know, could the dreamer hear that and then could they respond with three sets of left, right, left, right, and that became you know, one of the things that we found to be fairly reproducible were simple math problems that the dreamer did not know in advance, but then have to do the calculation and then respond back with the appropriate number of vibe movements.
So you haven't yet told us how you got the information.
In yes, So, as it turns out, when the brain is sleeping, it doesn't completely shut off from external stimuli. And I think we all have probably had this experience where an alarm goes off and somehow it gets incorporated into the dream. You know, it's a it's a siren, or it's a police car. We needed to have some auditory pathways available just to survive, right, we are sort of at risk when we're asleep. So we took advantage of that, the fact that there is selective pass through
of auditory information into the dream. And so it was once the dreamer was in rem sleep, and once they signaled that they were loocid to the left, right, left, right, then the math problem was just spoken, just spoken in a you know, a regular normal voice.
You mean, the experimenter says, it says, what is six minus three, right, yep, And the lucid dreamer hears that, and what is the experience of hearing it in a lucid dream.
It varied, you know, because at that point, you know, the dreamer is incorporating this external stimuli into the dream.
You know.
One person reported that they were in kind of like a residential neighborhood and they were looking at the house numbers and when the experimenter said, you know, the six minus three, the house number just changed to that and they solve, you know, six minus three. So each dreamer reported a different sort of subjective experience of how it got incorporated, everything from just hearing the words themselves to seeing the dream somehow communicate the math problem.
And once they have heard the question in some way, then they use their eye movement to, for example, look to the left three times, bang, bang bang, even though they're in their dream, they're talking to the outside world through their eye movements. That's correct. Cool. And you guys found that you could do this bi directional community.
Yes, and not just us. There was four labs. It was a great collaboration across France, the Netherlands and USA. And you know, now it's not one hundred percent of the time. But you know, it was enough to sort of say, this is way above chance that people are actually hearing these and responding back with the right numbers, and so I think it'll lead to a lot of interesting future research.
What happened when it didn't work, was it that people just simply didn't respond or they were answering the wrong question.
Yeah, by far it was a no response. There wasn't an actual response to the math equation. Now, we were also pretty harsh on ourselves. We had three independent scorers and there had to be a consensus that you know, it was the actual number of eye movements to match the math problem. So you know, with that, I think again it was rigorous science and that's what you need for something that's so unusual like this. But it was
above chance. And one of the things that is was also a little bit challenging is you know, remember we talked about the dream task, and so we did get people waking up and saying, hey, I had the Lucid dream, but I'm sorry I forgot to signal, and so you know, that kind of shows that there is sort of a progression of skill that you can get Lucid but then to remember to signal that you get lucid is one thing that you need to do, and then to be able to hear the input is another thing that you
need to do and then be able to communicate. So you know, there's there's multiple points of failure along the way.
And did you guys do other tasks besides the math problem?
The US group focused on the math problem, the other groups did. They did some interesting things around preferences. They wondered if preferences were the same, you know, in the dream world versus the outside world, and I think they found some you know, kind of interesting results there. It was almost like the dream the dream personality had some different preferences than the non dreaming personality. So that's that's kind of fascinating.
Can you give us an example chocolate?
You know, it's like, do you like chocolate? And the the outside was was yes, and the but the dreamer didn't like chocolate.
Fascinating. And you know, there was a stety years ago which one of my favorites, which is asking the question of whether dream time corresponds to real time. And the way this was done is the loocid dreamer when they become lucid. They you know, give a signal and then what they do is they, let's say, look the other way, They look to the right, and they estimate five seconds inside their dream, and then they look to the right again.
And of course in the outside world you can look at the signal on the electro oculogram and you find that in general, dream time corresponds to real time.
Yeah, I think that we liked the premise of Christopher Nolan's inception that you know each layer in the dream, you know the time changes, but we don't really have any evidence that you know, you can estimate and you can count that it's about the same. Now, it doesn't mean definitively that dream time can't be different, but I think that when people ask me, well, it seems like it was so long, what I come back with is like, well, think about a movie, and how does a movie feel
to you. You can watch a two hour movie and it can be over a lifetime. There's cut scenes, right, And I said, you know, dreams are very similar. There's these cut scenes, and so they can make the experience of a twenty minute dream session can feel like you know, hours. But so far, the evidence shows that it's about the same amount of time.
That's exactly right, you know. I remember years ago I was on a road trip with a buddy and I fell asleep for just a second. I woke up and he had noticed that I just closed my eyes and then woke come up, and I told him about this dream that I had. But the dream took a long time to describe. But the dream itself was just a moment. In the dream, I was standing on a roof and I was looking over the city and the city was flooding, and I felt so guilty because I had left the
sink on. I knew I had left to sink on and it was my fault that the city was flooding. The dream itself was just a second, but in order for me to explain it, I had to explain this false, implanted memory of having left the sink on and so on, and so often there's a lot of confusion about time this way. But yeah, I thought that was a fascinating study about dream time and real time being able to
correspond that way. Okay, so JB, tell me about some other cool experiments that have been done in lucid dreaming.
Sure, Well, one of the ones that I think is perhaps the most notable was nineteen eighty three. We have to go a ways back, but it's an interesting story. So there was this was when Stephen was doing his research and there was a grad student, Beverly de Orso.
And as it turns out, not even the grad students under Stephen, you know, they don't always get lucid every night that they're hooked up to the machines, and it is very costly to hook up the folks, and so when they do get lucid, they're required to write down their dream in detail. Well, this one night, it's clear she got lucid, she did the signaling, but then there was nothing in the dream journal. And Stephen asked her, he said, you know betterly, why why is that you
know that this is really important? She got kind of embarrassed and she said, well, I had sex in my dream. And He's like, that's nothing to being embarrassed about. How about we experiment and do that and she was up
for it. And so Walter Greenleaf was part of this as well, a distinguished Stanford scholar, and so they were able to hook up additional equipment to you know, measure things that you would think would be necessary for orgasms such as vaginal blood flow and muscle contractions and things like that. Very scientific and so so the next night she went to sleep and she got lucid. And the funny part of the story is that she gets lucid,
she's in the lab. She remembers the dream task, but then she sees she's in the lab with her lab mates and she's like, no, this isn't happening. I'm not going to write about this. So she flies out of the building and finds a random stranger to have her dream sex with, and then of course she wakes up and reports it. And it is quite amazing that all the responses that you would expect for a full sexual response were measured in the equipment.
So she was able to achieve orgasm from a lucid dream, from a lucid dream, and they were able to measure it in consensus reality. So you mentioned the two things they're flying and having sex, which I understand are the two most popular things to do for people who become lucid. What else do people do when they become lucid?
Those are by far the most common things. I think you know other people are they like to meet people. You know, there's sort of a desire because you can meet a celebrity or you can, you know, go to a novel place, drive fast cars. You know. One of
the things that I thought was quite interesting. Robert Wagner is a long time practitioner and he writes many books, and I met him at a conference and one time he said, you know, Jamie, in my experience, for the first five years, people are very headen stick in their approach to lucid dreaming. But after that you get into the more interesting stuff where you can do more self exploration and things like that. So I think that was
true in my own experience. And then as I've met other lucid dreamers, depending on how many years they've been lucid dreaming, they're either still driving fast cars and jumping off the buildings or they're doing other stuff.
So let's get back to this issue of how to lucid dream because I know a lot of listeners will want to start practicing that. So there's this issue of doing reality checking. You flick your tooth, you turn the light switches on and off, you look at texts like in a book or on your watch, You get in the habit of doing this all the time until such time that you do it and it doesn't work, and
you think, wait, why didn't that work? And then you realize, but what technologies can help us move along to have lucid dreams?
Well, the one technology is more pharmological, So there are some acetacoline enhancers that have been studied. So glant tomine is one of the ones that has been been studied and that does induce tends to increase the ability to have dreams and more vivid dreams, which then leads to lucid dreaming. So that's certainly one intervention that I would put in sort of the technology realm. You know, there are many kickstarter you know, this is interesting because I've
tracked this for years. There's been many kickstarters since Steven's original Nova Dreamer, which was, you know, a mass that would flash lights when you became lucid.
So wait, actually, let's let's let's zoom in on that for one second. So the idea was you have a mask that's measuring your electro ocograms, measuring your eye movements, and it sees that you've gone into rems sleep, you've gone into dream sleep. Your eyes are moving back and forth, and so then it flashes let's say, red lights at you. And the idea is that the dreamer is having this normal dream and thinks, wait, what are all these red
lights going on? Why is everything flashing red? And then thinks, oh, wait, I must be inside a dream, and that what's the element that you need in order to turn lucid.
Right, It's like a forced dream sign. So, because you remember we talked about how dream signs are the triggers, well, the red lights become something you can kind of bank on. So when you go to sleep, you can still do the mnemonic induction. You can say, next time I see flashing red lights, flashing stop signs, anything to do with redvite,
I'm going to know that I'm dreaming. So you still practice that mnemonic induction, but it's just sort of guaranteed because you're going to introduce that stimuli directly.
And how well do those work?
Risingly not as well as you'd think. So you know, years later, I was looking at sort of the comparative. Every five or ten years, somebody does a meta analysis of all the different methods and stuff, and so you know, recently a meta analysis showed that that type of induction isn't as robust as one would think. You know, the best induction methods are really combinations of things that we've
talked about. So when you combine reality checks with wake back to bed and if you you know, add an aceta coleen, you know, enhancer, the kind of the best results are fifty percent in you know, two or three nights, seemed to be in sort of the realm of possibility. But to date, there really hasn't been any technology like you know, the Nova dreamer, or there's you know, the REM dreamer, which doesn't really know if you're in REM, but it just sort of randomly, you know, flashes lights throughout.
I've heard some researchers get their hands on something called the IBAND, but I don't think that's ever been really available to the general public.
And what what is that? What is the I band?
The I band is is very similar. It you know, measures the EEG and then you know, it flashes a red light you know, when when the dreamer is there. But I think one of the things that I learned from Stephen and as I've practiced lucid dreams and I've helped other people over the years, it really does come down to motivation. You know, he would say that that, you know, when he had to do his pH d, when he and to have loocent dreams in order to get that degree, that made all the difference. And and
I think that's been my experience too. So if you have the motivation, if you know, if you learn enough about what's possible, then then you'll you'll have it. I mean the mind does respond. There's an element of just sort of the mind body connection of having this intention to enter this altered state of consciousness, and then you know,
you're motivated to practice the reality checks. You're motivated to wake up after four and a half hours of sleep and stay up for ten or fifteen minutes, and you know, rehearse a dream that you want to have. That's kind of we didn't talk that much about it, but if you do the wake back to bed method after waking up after four or five hours, you do want to sort of rehearse. You want to just sort of fill
your mind with lucid dreaming. You know, the lucid dream you want to have, where you want to have it, what smells, And then as you lie down, you know you're telling yourself, I want to remember that I'm dreaming. The next time I'm dreaming, I want to recognize that I'm dreaming or remember that I'm dreaming, and then you're more you know, more likely. So that's sort of the best set of methods to have a lucid dream, but it takes a lot of motivation to do that.
A couple of episodes, I talked about what happens when we're asleep and how the whole brain does this change over The whole factory of the brain switches over from waking state to sleeping state, and you know, we lose consciousness as one of the results of that. And what's so interesting about dreaming is it's a form that is like consciousness and lucid dreaming even more so, how do you see the relationship between the lucid dream and the conscious state.
That's a great question and that's been sort of hotly debated in the dreaming world and the lucid dreaming world for some time. And because it is difficult to get subjects lucid with the expensive equipment like an fMRI, there's not a lot of neural correlates. But I will say there have been studies of like n of five, you know, n of six, and based on that data, I believe it is a hybrid state. And that's you know what the authors of that study, Ursula ass is the lead
on that that it's a hybrid state. It's not quite rem and it's definitely not quite waking, but it's it has little characteristics of both. And again that's sort of objective measures from the EEG and from fMRI, like what regions of the brain are activated versus not, and what
type of power and amplitude. And I think, you know, if I'm honest, my own experience is fairly similar that when I'm in a lucid state there, I'm most often entering that from a period of awakening, you know, so like the wake back to bed method, and then you get into this sort of hybrid state. And again many
people subjectively know what you're talking about. You're like, oh, yeah, I was on that car trip and I zoned out for a little bit, and then you know, I had a weird hypnogogic imagery or I had a weird thought that just didn't feel like it was mine. And so I think it is hybrid. And if you need a lot of sleep, you'll be a deep sleeper and you won't have a lucid dream if you are able to.
If you get up multiple times in the night, you're probably more likely to have a lucid dream because you're entering waking state into the dream state multiple times.
You know, when I think about lucid dreams, I think about Stephen Leberge as the guy who pioneered all this. But I'm just curious, was there any indication of these in the literature, either the scientific literature or in writing before Stephen.
Yes, there's a researcher Keith Hearn in Europe right about the same time as Steve that was doing some of these experiments with left right, left right, and so he certainly gets mentioned a lot of times. And then you can, you know, go back to you know, nineteen early nineteen hundreds, and you'll see some writings of sort of this idea of being conscious in the dream state. Ben Eden, I believe, is who they cred that to. Some have even pointed
farther back. I can't verify whether Aristotle talked about this state of consciousness or not, but I tend to focus on the more modern folk.
Are there any downsides to lucid dreaming.
So some people have raised that concern, and I think it's a good concern to raise. And the good news is people have actually started to study it. You know, lucid dreaming research has really exploded in the last ten years. And so as that research has gone forward, of course people are looking for kind of novel angles, and so one of the novel angles in the last five years is can you show some some downside. So the things that they looked at were does it increase dissociative behavior?
And so, you know, because in a lucid dream state, you know, you're in this kind of altered state of consciousness that might even share some characteristics of things that are perceived as negative where you're disassociating from yourself that's not normally a good thing in waking life. And they looked at things like sleep quality. Does you know people practicing the white back to bed method, does that interrupt sleep? Does that actually lead to less sleep? And then they
looked at does it lead to nightmares? Are people, you know, with all this kind of flexibility, does it somehow introduce nightmares? And there haven't been a lot of studies maybe you know, five or less and I would say the consensus across this is that the most negative impact really is in the quality of sleep. You're just not sleeping as as deeply, and so you would I would never recommend that people try to lucid dream five nights, you know, a week.
But all those other things that they looked at, they didn't find evidence for it. It didn't increase some sort of disassociative behavior, and there really was more positive mood impact. People really do feel good about lucidream. It's it's like almost like an accomplishment, and they tend to talk about it and that leads to sort of an elevated mood. But it does take away from a good night's sleep, and therefore not something people are going to do every The.
Other social disadvantage, of course, is that if you're constantly walking into a room and flicking the lights on and off and seeing if you can knock your tooth off, people might think you're strange.
Yes, I think it's fair.
So what's the research that's really exciting that's going on right now?
So I think that one of the groups that is receiving a lot of funding is Martin Dressler out of the Netherlands. He has been gathering more and more students on funding that he's getting. We caught up briefly at World Sleep in Brazil and really interesting experiments that really are building on the things that we've already talked about.
So think about the natural extension. If you can have two way communication between an experimenter and a dreamer, is there anything scientifically or from an engineering perspective that prevents that happening from a dreamer to another dreamer? And the answer is no, So you can bet that some people are working on that, and you know, might even be making PhD thesises out of a dreamer to dreamer communication. There's another group that I know less about, but they're
certainly publishing a lot of papers. I haven't met these researchers in person, but they have published on mind controlled avatars from within the Lucid Dream. Because if you think about it, you know, in the BCI world, it's not that difficult to hook somebody up to an ECG and have them control some sort of robot or some sort of avatar. Well, of course, a natural extension is like, well, in a lucid dream, we've just said, you can send off signals with your eyes, could you use that to
control an avatar? And so indeed they published a paper on controlling a car avatar just from within the lucid dream. So, you know, just to make sure we know what we're talking about. They're in a lucid dream. Their task is to somehow drive a dream car, but they've been hooked up in a BCI format to actually driving a car in you know the.
Lab by the way, BCI's brain computer interface. So but what in this case EEG or what were they hooked up.
With EEG and EMG?
So, okay, electromiagram, so it's measuring their muscle. Where was the EMG hooked up the EMG? I'm not quite sure where. I again, I haven't looked at that one in detail. I sort of skimmed.
It and thought this would be definitely worth, you know, talking to them and finding out more. The other thing that they did that I've always wanted to do. I what's kind of fun for me is I've had a lot of these ideas over the years, and then now
I get to see researchers implement them. The other study they did was what happens if you consume some sort of pharmological substance in a lucid dream says, you know, if we think about the Beverly de orso clearly, you know, by having an engagement of a certain type in the dream, such as sex, it led to a physiological response. So a natural research question is like, how far does that go?
When you drink alcohol in a dream? Does it have any kind of physiological effect if you take ritilin or if you take some sort of you know, illegal substance. And they have a paper on that, and it turns out that psychoactive substances taken in the dream have a stronger perceived effect by the dreamer then like let's say alcohol.
And then they again, according to their research, about twenty percent of the respondents who were able to remember to do the intake had some subjective feeling of that even after waking up. Now again, I think that's the type of research that like, hmm, that's very interesting. But I want to see that replicated, and I want to see a you know, with you know, thirty people, forty fifty people. So, but I think it's just it's interesting. It's an interesting thought.
What is the claim there though, that they're seeing the placebo effect of a psychedelic they're just you know, when someone says, hey, you've taken this drug and then you feel like you're drugged even though you're not. That's the idea of that exactly.
I mean, that's even the title of the paper is is like, you know, placebo without deception. So it's a it's a known, you know thing that you are just taking, you know, something that is not real quote unquote in the dream. But then the placebo effect is is really well studied. I mean, you know, even again some some colleagues at Stanford are looking into that quite quite extensively. So I think that's a novel and a very interesting application of lucidreaming.
It'll be really interesting to see whether this leads to people being able to heal anything about themselves this way using a placebo effect with you know, medications in a dream and their leg gets better or some disease state they have.
That's right well, And I think the other thing that we haven't talked about that's worth mentioning probably one of the most research areas that's currently therapeutic is PTSD, and so they're using PTSD and lucid dreaming to help people overcome that trauma. And so if, especially if there's a reoccurring nightmare, it's a bit counterintuitive, but what the participant has been told is that whatever you're dreaming, even though it's very negative and it causes, you know, a strong reaction,
it's really a disassociated part of yourself. And so in the Lucid dream, you have an opportunity to consciously, in a very safe environment, you know, act in a different way. And so an example of this that I'll just you know, I'll make up a fictitious example, but it gets the point across. Let's say that I have a dream and in that dream, a robber you know, comes in and breaks into my house and is you know, strangling my son, and you know, Lucid dreamer, and they say, I get Lucid.
It's like, no, this is you know, my dream sign happened. This is my house, but it's in Indiana, And you know, I might be tempted to turn into the Incredible Hulk and just throw that robber, you know, out of the building. Well, sure I could do that, but then if this really is a recurring nightmare, it's going to come back. Instead, if I recognize it's a dream, and I remember what my therapist has told me and say, hey, this robber is really a part of me. Then I show it love.
I actually say, hey, you want to tell me something. I love you. You're just a part of me. What's the message you have for me? And this robber might turn to me, he might transform. People talk about it transforming into something beautiful, and might say, you're neglecting you know that the play. There's you, you're you know, your inner child wants to have more fun or more and
more play. And that's just, you know, kind of a light example, but there are many examples that are you know, very significant and that people have had substantial healing where that you know, monster or that aggressor turns into something beautiful. And then often they'll talk about an experience of it kind of coming into their heart. And I think that is perhaps at this point in time, from everything I've seen, it's perhaps the most beneficial application of lucid dreaming is
that you can reintegrate these difficult memories. You can reintegrate these difficult parts of your past because the environment's very safe and somehow you're operating below the conscious mind, you know, like this. Even though you have some conscious control, you still have about you know, ninety to ninety five percent of the dream is just generated outside.
Of your control.
So it's a really unique aspect.
So there are all kinds of therapeutic roads that might be discovered in the future as we get better and better as a society at implementing lucid dreaming. So, JB, you've been exposed to lots of the great minds in lucid dreaming. Has anyone else come across your path that said something influential to you?
Yes? At Google, actually I found Ray Kurzweil. Many people may no Ray kurzwhile he's considered a futurist, a great thinker, has many patents under his name from his earlier engineering days. I found out that he was at Google and I came across some of his writings on his blog and he mentioned, you know, lucid dreaming. So I initiated contact
with him and we had many good exchanges. And the way he described it I thought was very fascinating, you know, coming from an engineer's perspective, And he said, you know, JB, I was trained as an engineer, but in the Lucid
dreaming state. I find that part of the mind that has these constraints that I've sort of learned are you know, hardwired, they get looser, and so I can in this sort of hybrid state, I can come up with new things that are inventive, and when I wake up, maybe you know, eighty percent of it really isn't feasible, it's breaking the laws of physics. But that twenty percent leads to something.
And so that is part of why I did get quite excited about it, and I thought, you know, engineers or creative types really can ben ait fit from this. And you know, taking that one step, you know further, you might say, well, how what what exactly? Well, remember when we talked about you know, the first five years, you know, becomes a bit you know, hedonistic. After that, well, you can actually just call out to the dream world. You don't even have to invent a scenario. You can
just say show me something beautiful. Let's say you're an artist and I've done that phrase and you know, out of the ground form this incredible marble, you know, statue that I wish I was, you know, a sculptor, and I think, you know, it's getting to that aspect that Ray talked about, like, you're in this unique state imagine as an inventor, as a writer, you could just prompt and so you know, when I see chat, GPT and prompt engineering, I immediately think of you need prompt engineering
for lucid dreaming because you literally can just prompt your mind. Show me what you know. I'm most afraid of, show me something beautiful. Stephen's favorite question is show me the best version of myself. You know, that was the question that he thought, you know, leads to sort of the
highest expression of what's possible. And so I would really encourage people to, you know, learn how to lose a dream and then think about what do they want to see, what do they want to create, what do they want to perhaps, you know, explore about themselves, because there's really no other place where you can do that that is so safe and it's just coming from your own mind and you don't need to use any substances, you know, to get into that state of consciousness.
So that was my interview with Jonathan Barnt, and what we see is that first of all, achieving lucidity isn't easy, but if you practice and get good headed, there are opportunities for personal insight and problem solving and artistic inspiration, possibly overcoming nightmares, and all kinds of exploration. So as a reminder, if you want to try lucid dreaming, there are several techniques to pursue. First is keep a dream journal, write everything down from your dreams when you wake up.
This is really the only way to do dream recall, so that you can then look across a bunch of your dreams and start to recognize dream signs. In other words, this sort of wacky thing shows up in my dreams a lot, but rarely or never in real life, so when you see it, you should be more likely to recognize that you are dreaming. Then there are all the techniques for reality testing. These all involve checking your environment
several times a day to see whether you're dreaming. So, for example, you look at a digital clock and then you look away, and then you look back at the clock again to see if the time has changed in some weird way. The key is to get into the
habit of doing this. Most of the time, you'll be doing this in real life and it won't change, And then at some point you'll do that habitually in a dream, and then you'll say, whoa or is John Nathan mentioned you can try pinching your nose and trying to breathe in. You get in the habit of doing that several times a day, and in real life you'll never be able to breathe in. But at some point you'll do this and you'll breathe in and you'll think, Wow, that's weird.
Oh wait a minute, And there are lots of techniques you can try here. Another one is placing your fingers against the palm of your other hand and trying to push them through. That won't work in real life, that can sometimes work in a dream. So think of what techniques you might want to use for reality testing. And the idea is that if you get in the habit of running these checks frequently during the day, it makes it more likely that you'll perform them in a dream,
and that can trigger lucidity. There are several other kinds of complementary techniques, some of which Jonathan mentioned like the wake back to bed method, which involves waking yourself up after five to six hours of sleep, and you stay awake for a little bit and then you go act
to sleep with the intention of entering a lucid dream. Now, this method works because you have more rem sleep in the second half of the night, and so that enhances the chances of becoming lucid, and most lucid dreamers find that combining techniques increases their success rate. Just be aware that this requires patience and a lot of practice. You probably won't achieve lucidity on your first try, but keep trying and you'll get there. Okay, So let's wrap up.
This was the third of a three parter. The first wason Why Brains Sleep, The next was on why Brain's Dream, and this episode covered a rare and special form of dreaming, lucid dreaming. So hopefully you've learned several things that you didn't previously know. But truthfully, there are still a lot of things that we still don't understand. As just one example, there's the issue of the false memories inside a dream.
So I mentioned it to Jonathan Earl that I had had this one second micro sleep when I was on a road trip with a friend, and when trying to describe what happened, it took a long time. Now, the reason was that the dream itself was simply I was standing on the top of roof looking at a city flooding.
But I had a whole set of false memories how I had left to sink on because I wasn't thinking and not taking appropriate responsibility, and I had all these feelings of guilt because it seemed so stupid that I had done that. I felt regret, And now I was in a situation of figuring out what this meant for the city and for me personally, and how much trouble I was going to be in, how guilty I felt about flooding everything. But the dream itself only took a
fraction of a second. And the question is where did all the memories of having done that come from? And why were they so believable to me in that moment? And another related question I've always had is how can characters in our dreams surprise Someone will often say something to you in a dream and you'll think, Wow, that doesn't feel like something I would have thought of, But
it was your brain that came up with it. Now, just to be clear, this can result from random hurricanes of activity in the depths of your unconscious brain, all of the stuff that you don't have access to awareness of, and it doesn't necessarily have to be meaningful, like a deep hidden message. But again, the part that weirds me out is that your brain can serve up this very weird stuff to you and it is totally believed by you, which should make us appropriately suspicious of all the things
that we believe in waking life. As you know from this episode In the last I don't think that dreams necessarily have meaning, but they may provide an interesting tool to explore the boundaries of our own consciousness. If we agree that the mind is the final frontier, dreams may be one way that we can navigate its depth. Until next time, keep dreaming and I'll see you in the
next episode. I'll link lots of papers about lucid dreaming at eagleman dot com slash podcasts, so don't forget to go there, and I'd love to hear about your experiences or your questions about lucid dreaming. So send me a note at podcast at eagleman dot com to let me
know your thoughts. If you enjoy these episodes, please consider leaving a review on your favorite podcast platform, and check out and subscribe to Inner Cosmos on YouTube for videos of each episode and to leave comments until next time, I'm David Eagleman and this is Inner Cosmos.