The Infinite Monkey Cage - Science of Dreaming

Episode Date: September 30, 2019

Brian Cox and Robin Ince are joined by comedian Bridget Christie, neuroscientist Professor Penny Lewis and psychologist Richard Wiseman to explore the science of dreaming. Our dreams have fascinated humans for millennia and then Freud came along and told us they really did mean something, and mostly they were about sex and anger. Was he right? Why do we dream and can we find meaning in the content of our dreams? Can our dreams help us solve problems, give us new ideas, help us write a symphony, even if they can't predict the future? The panel also discuss what is going on in the brain whilst we sleep, and how memories are formed and consolidated while we snooze. It turns out the phrase "better to sleep on it" has a strong scientific argument.Producer: Alexandra Feachem

This is the BBC. This podcast is supported by advertising outside the UK. BBC Sounds. Music, radio, podcasts. Hello, welcome to the Infinite Monkey Cage podcast. I'm Robin Ince, next to me is Brian Cox, and we hope you enjoy this podcast. If you are confounded by it, don't worry, most of us are. I'm Robin Ince.

And I'm Brian Cox. One of the great milestones in the journey to understand the human unconscious occurred when Sigmund Freud published the Interpretation of Dreams. And now I'm going to tell you what it means when you dream of a harpist. But anyway, the other great psychotherapist of that time, Carl

Jung, considered one of his most influential dreams to be the one where God did a big poo on basel cathedral destroying the cathedral on impact and uh that's entirely true by the way is in his autobiography said that the dream that really changed my life i've never dreamt of god i mean the fact that it's god and a poo in a cathedral you can see why the b-ram the weirdest dream i had right and i thought this must be because we're doing this show on monday i had a hypnagogic dream just so i was falling asleep where i suddenly saw corf castle two turrets of corf castle start to embrace and kiss each other and i have no idea

it's the first time i've had any form of erotic masonry dream i have no idea i've never even i i woke up immediately going, where the hell did that come from? I've never thought I'm that mentally well, but I never thought I'd have an erotic masonry dream. How did you know they were kissing? What were they doing? Well, I didn't see...

It was more that the way that the Corfe Castle turrets actually started to embrace. No, they didn't quite... It was more just the embrace. The embrace was kind of more sensual than, I suppose... I think you've made it sensual, Robin. It doesn't sound like there's anything sensual about it at all. I think there was two buildings and you've gone,

oh, I think they're kissing and have made up this whole... No, no, no, I wasn't. It was... Well, it doesn't sound like... There was only one building. It was Corfe Castle, right? So it has a very strange kind of solipsistic air as well, right? And just...

So he was embracing itself, the castle? Yeah, yeah, yeah. Oh, don't go there, that's rude. Anyway, so that's one of the weird... I'm never going to Swanage again. Why did you go with turrets? Well, I didn't go with it. This is the whole point.

But from a Freudian perspective, two turrets. From a broad... LAUGHTER It's disgusting, that's what i'm saying from a broadcasting perspective i think it'd be better to introduce the panel before you get involved in the discussion just tradition oh in any way do the narratives of our dreams mean anything at all why do we need to dream is there any purpose to them do they filter our previous days experience into something comprehensible, or are they just an emergent product of consciousness?

To discuss this, we're joined by a panel of experts, all of whom have done a lot of sleeping. Fortunately, they've also spent time awake, and when they are awake, they've spent quite a lot of time thinking about the gobbledygook of our mind's activity. And today's panel are... I'm Professor Richard Wiseman, psychologist at University of Hertfordshire, and my most memorable dream was Corfe Castle with two... I'm Professor Penny Lewis, I'm a professor of cognitive neuroscience at Cardiff University. And my most memorable recent dream was about three weeks ago,

I dreamed that I had been elected prime minister. It was terrifying. And I was elected, and I was on stage, and I had to give a speech to the nation live right now. Yeah, it was awful for me, but I didn't really think about it from the perspective of other people, but I guess it would have been pretty awful for everyone else. No, it would not. I would have strongly supported it.

Do I have to say I'm a professor of something as well? You can if you want. You can be whatever you want tonight. OK, I'm Bridget Christie and I'm a professor of something as well? You can if you want. You can be whatever you want tonight. OK, I'm Bridget Christie and I'm a professor of every subject you can think of. And my most memorable dream was last week and it was this. I was in my dad's house and he lives in Gloucester and I was in his front garden and he's got a really nice neighbour who always comes over and talks. And from her roof a phoenix flew down which is not real and it flew down and there was a a penguin but it had a sloth's head and it was just wandering around on the pavement

and and i was like oh i think we should pick it up because there's a phoenix coming swooping down and then josie long walked down the street and said, I'll get it, I'll get it. And this is our panel! Bridget, the first question we'd written down on the script for you is, are you one of those people who tells everyone about your dreams? But now I think we know the answer.

I have disturbing dreams and funny dreams and so I wouldn't just say to the postman oh thank you do you know what I dreamt last night it would only be if someone else said that they had a weird dream and I would say I did

as well because the one that you just said there is a wonderful, I mean that is an entire Jim Henson first scene that you've given there. Yeah, I have a lot of those. But I have some where I wake up literally boiling hot and sweating.

And they're completely nightmarish. And I couldn't even... I mean, even thinking about them makes me worried about my mental health. Because they've come from my brain. But also, they're not about anything that's happened that day or... This is the best episode of In The Psychiatrist's Chair we've had for ages. Richard, in terms of the actual scientific study of dreams,

where does it start? I mean, does it start with, for a lot of people, they would imagine it would be Freud in the interpretation of dreams. Is that the first time, the attempt of a scientific study uh well it depends on you by science if you if you're looking at uh the the piece of research that kind of really kind of got everyone very excited about dreams and if you go to research rather than freud you go to the early 50s with uh eugene aserinsky who is a phd student at university of Chicago, and he does this amazing piece of research. He's got an EEG machine, and he gets his son, and he connects his son to the EEG machine, and he lets his son sleep.

He's not a very giving man in that sense. And he tries to monitor him all night, and he notices about 90 minutes in that the EEG, which goes obviously down into deep sleep and it's all looking very relaxed, suddenly gets very agitated. So he thinks, obviously my son has woken up because this looks like consciousness. He goes in and his son is still asleep. So he wakes up his son and his son reports a dream. And that's suddenly when psychologists and scientists realize there's a particular state, a dream state, particularly REM, rapid eye movement. And if you wake people up once they're in that state or shortly afterwards, you get a dream. And that kicks off the whole of dream research.

Penny, could you outline a sleep, a typical night's sleep? So how often do we dream and these phases that rich talks about how do they come in so firstly answering that how often do we dream um there is this idea that we only dream sort of maybe in one stage of sleep but actually we dream all the time so we can dream and wake people know daydreams and we also dream in every state of sleep so that is a you know constant thing it's not just one state but in terms of every state of sleep. So that is a constant thing. It's not just one state. But in terms of every state of sleep,

well, that already gives away that there are different states. There's this maybe myth that I think needs debunking that the brain just switches off when we sleep. It doesn't switch off. The brain is actually incredibly busy when we're asleep. And what it does is work its way through four different very different very precise states that we call stages one to three of non-REM sleep and then REM sleep and it works through these in cycles of roughly 90 minutes although

there's a huge amount of variability in that and And then what these look like is, so stage one, it's kind of transition. So as you fall asleep, essentially your brain activity just slows down a little bit. And that's quite brief. And then if you stay asleep a bit longer, you move into stage two of non-REM. And this is characterized by, so the activity has slowed down a bit more, but then you have these bursts of high-frequency activity that are localized over different areas of the cortex. So these are called sleep spindles.

They're about 10 to 16 hertz, so just high-frequency localized. And we think these are incredibly important, actually, for some of the processing that's happening in sleep. So there's characterized stage two. And then if you stay asleep through this, you'll move into what we call slow-wave sleep or really deep sleep. And this is characterized by these really high-amplitude oscillations

where millions of neurons in the brain all fire at the same time, and then they pause, and then they fire at a frequency of about 0.8 hertz. So that's just a bit slower than once per second. And that creates, when we look at the EEG that Richard mentioned already, it creates these huge high-amplitude oscillations. It's totally different than anything you'd see in wake. It's really hypnotic watching these while someone's asleep. And then if you stay asleep through this,

we'll move into rapid eye movement sleep or REM sleep, which I'm sure everyone has heard of. And this is characterized by rapid eye movements under closed lids, but also somewhat paradoxically, the brain activity, the brainwaves at that time look very similar to how they look during wake. So none of these high amplitude, slow oscillations, none of these spindles just looks like you're awake, but in fact, you're deeply asleep. And as many people will be aware, it's REM sleep that people talk about as dreaming sleep,

even though we have dreams all the time. The reason for that is maybe because dreams are a bit more prevalent in REM. So about 80% of the time when people reason for that is maybe because dreams are a bit more prevalent in rem so about 80 of the time when people are awoken from rem they will report a dream and also because these dreams tend to be more emotional more bizarre more fragmented those are all characteristics of rem dreams that's very interesting because i i didn't know that so i just assumed this i suppose an urban myth essentially what you're saying that you dream in rem sleep and your brain is doing something else in the other phases of sleep so that's not that's not correct no that is an urban myth that's a good label for it and the way we know this is that um as sleep scientists what we can do is

we put electrodes on people's heads we can monitor which stage of sleep they're in and then we can cruelly wake them up whenever we feel like it and we can ask them if they were dreaming and so people have done a lot of these studies and they can they know what proportion of of the time people will report a dream so from REM sleep as said, it's about 80%. From that deep, slow-wave sleep, it's closer to 50%. It is less, but there are still dreams. The sleep spindles that you described, because that's a 90-minute cycle, and then we go through another one, another one. Are they randomly positioned in the brain,

or are they in specific centres? Are they different all the way through the night? So the sleep spindles are a really interesting topic to me. They're quite central to my research, so be careful, because I could go on and on on this topic. You'll have to interrupt. So they're not random. So what we think is actually that the sleep spindles

are occurring in areas of the cortex which have been involved in learning during the day and where you've learned something and you need to process that information. We talk about memory consolidation, so consolidating that information. And we think the spindles are important for consolidation and processing.

So in terms of when I was mentioning before that hypnagogic castle erotica moment at that point of just falling asleep and another i suppose a common one that people would think of is that moment you fall asleep and then you briefly have a dream where you put your your your foot goes into a hole or something and you have that flinch you have that moment where it appears your your body is still reacting to what are we seeing are we seeing anything specific we can talk about in terms of the lowering of function in in the brain or the heightening of function which is creating this very rapid imagery and sometimes these actual physical reactions to the visions in our head so so there are different ideas about this i think it's probably good to preface it with we don't really know right um as with many things about dreams we don't really know but but one idea

um it's called the activation synthesis hypothesis um and this comes from alan hobson's it was a harvard psychologist and what he suggested is that so you're getting random activity in the cortex in REM sleep this is stimulated by actually there's an area in the brain that has these random huge activations and they kind of percolate up and they randomly activate the cortex and so what he suggests is that the brain so you're getting these activity patterns, and then the brain has to make sense of them. And so it kind of creates a story around this random activation. So that's one of the ideas. There are all kinds of problems with this idea. One problem is, of course, it's not just REM sleep.

And you do get dreams, as we've said, across the other stages. But the more bizarre ones are in REM sleep. And so if you're trying to sort of piece things together... So you could have had a PGO wave coming up from your brainstem that is activating some kind of a remembered representation of Corfe Castle, and then maybe it was also activating some sort of shady, dodgy movie that you watched recently. And then your brain...

Do you remember which one that was? Yes, I do. It was The Lady Vanishes. It was the bit where Dane May Whitty... Anyway, look, you don't need to know. How do we know that... So a lot of this research is asking people, so you wake them up and ask them, how do we know that what they recall in in that moment as they wake up

and tell you has got anything at all to do with the the sleep previous to that and that time scale you know how do we know that dreams really happen in other words i mean it's possible that people are lying um which they do in our research all the time it's extremely annoying um you know i mean they come in uh you wake them up, and you say, what was the dream? And they're just off on a lie. And then they get together afterwards, they laugh at you.

It's living hell, Brian, doing this stuff. It's all very subjective. But what we do know, though, is if you have, say, I don't know, 40 minutes of REM, and then wake people up they report a long dream they report a dream which might be a sort of 30 minute dream if they've only got a few minutes of rem you wake them up it's a shorter dream so we know that the length

of rem roughly correlates with their their memory so that's that's some kind of indication and it's some kind of measurement you can do to to see to correlate that that memory of the dream with activity in the brain so people have tried to do that um but i'd say it's very early stages so there was a a really cool paper on this in science um from yuki kamatani in kyoto a few years ago and what they did is they got people to sleep in the mr scanner um and they sort of first they showed them pictures of apples and tables and chairs and you know lots of things and they kind of worked first they showed them pictures of apples and tables and chairs and, you know, lots of things, and they kind of worked out what was the pattern of brain activity for each of

those things, so they developed with machine learning a classifier for each of those, and then they let them sleep, and then they woke them up lots of times and asked them, what were you dreaming? And then they had their dream reports, and they knew what they said they were dreaming about, and they then, if they had any classifier that they they knew what they said they were dreaming about and they then if they had any classifier that related to that so the chair or the apple the table then they checked whether the brain activity actually showed signs of that and they were able to find evidence for this um which yeah is amazing it is an incredible thing is it that one day we're going to live in a world

where scientists will be able to know if I've dreamt of a chair. Well, to be fair, they could just wake you up and ask you, would be the other way of doing it. I mean, I suppose we should say, I mean, what Penny's describing there is quite regimented. So pretty much everyone will dream about five times a night. Those dreams start off, in terms of REM, start off very short and grow longer over the night.

It's almost a night of two halves. So in the second half, a lot more REM than the first half of the night. And we just don't remember that stuff for the most part. So we tend to think we don't dream that much. But it's all going on every single night of our lives. Why can some people never remember any dreams at all? Well, I think part of that, I mean, so to remember a dream, you have to be woken up really very close

to the end of it or during it. So if you're a very light sleeper, and of course, with the sleep cycle, you're going down into this deep sleep and then up again for the REM sleep. If you're a light sleeper, it's very easy to wake up during one of them. If you're a deep sleep it's harder to do that so i think that's one of the correlates and it depends how emotional your dreams are if you're having a very emotional dream it might wake you up from it so yeah when i when i was in my 20s i used to be able to go back to sleep and finish dreams that's really weird did you want to though i mean that's the thing is when you're talking about your penguin sloth phoenix based dreams it was good dreams that i'd been annoyed that my sister had woke me up about and then i'd go well i think i'll just go and finish it off and then i would be able to but

could you control anything else about that dream because that sounds a lot like lucid dreaming i couldn't control what happened in the dream but i could pick up where I left off and carry on and the the the last part of it would never be very long but I'm a very light sleeper um so I don't know if that has anything to do with it well I think I think that you're going straight back into that that dream state I mean some people will will actually uh also like a soap opera over several nights they'll be having returning to the same narrative so we did a study where we were asking people to report their dreams night on night and some people have got this very long soap opera narrative so there was there was one participant uh who started uh dating george cluny in the dream obviously um and so she she met him in boots uh and and so we'd look forward to the

next night the next installment would come in what shop were they to the next night, when the next instalment would come in. What shop were they in the next night? They started going out on dates, and it was all going very well. And then he turned out not to be quite so interesting, and so she started cheating on him with Brad Pitt. And I was very jealous, because I don't remember my dreams, and they're certainly not like that. So some people have that very strong narrative.

The Brad Pitt, George Clooney thing you were jealous of or the the dream um both but she was controlling them that's isn't that odd no that's a lucid dream uh so no no these things were coming into her head like a normal dream so lucid dream you have some sense of control over it um and they're fairly rare some people are very good at having them. I've only had one, actually. Which was very frustrating. So I had a lucid dream. And in my dream I was in a shopping mall. And George Clooney wasn't in there.

There was no one of any interest at all. And most people, when they have a lucid dream, decide to fly. But I didn't get partial control over this. I didn't decide to fly. And instead I went and bought a pair of trousers. It's the first step. Well, yes.

I wasn't wearing any trousers in the dream so it wasn't an unreasonable thing to do. Where were you keeping your money? It doesn't matter. This is coming from a man who had two turrets embracing a few moments ago. So I went and bought my trousers, and I was really disappointed.

It's the only time I've had a lucid dream, and I went and bought a pair of trousers. That's a very disappointing brain. But you said it was lucid, so you should have been able to choose what you did. Well, this is the problem. I did. I remember thinking I couldn't lie. And then I thought, it's a tk max over there and uh it might be like cut price or something so i went over i love that idea going well i don't want to fly when i'm not wearing trousers if i've got time oh that's so good but this is an interesting because lucid dreaming

there used to be a debate didn't there about the idea that people thought it was kind of made up didn't they that those people who would say oh because I have a few friends who are quite obsessed with it, and they've learned various different tricks. I mean, first of all, what are the tricks, honestly, to both of you, that mean that people can train themselves to start to control what's going on in their dreams? It's really hard, actually, to be honest. So it seems to be a genetic thing. Some people are just naturally good at it.

If you're not, it's actually pretty difficult. But the way in which they found out about it was that the lucid dreamers said, well, I'll send you a signal. My eyes will actually go in a particular way in terms of eye movements. And during the lucid dream in REM state, they actually could send those signals via their eyes.

Because that's pretty much all you can move. You're paralyzed when you're in that state. So as a man, you can get an erection or you can move your eyes. And they went with the eye movements. So, yes, that's how they... I can see why you were buying the trousers. Should I go? Yeah. But there actually are a couple of methods

that people have been developing to kind of help them get into a lucid state. And you probably know more than I do, but one that I know that some colleagues of mine have been developing is similar to what you said so essentially people are wearing an eye mask that's got some lights in it some red lights and it's got some electrodes and so it can detect when they're in REM sleep and when they're in REM sleep the the red lights will sort of flash and what they're told is if the red lights flash, then you need to move your eyes

left, right, left, right, left, right to indicate that you are lucid, you know, because you have to be lucid to be able to do that. You have to be aware and able to control something to be able to do that. So what these people have been doing

is getting people to essentially just practice doing that in the day when they're awake. So they're wearing this thing, it flashes and you practice giving the cue. And just practice doing that in the day when they're awake. So they're wearing this thing, it flashes, and you practice giving the cue. And just by practicing that before you sleep, practicing it quite a bit, it seems to really increase the percentage of lucid dreams that occur. So actually, colleagues who are using this in studies,

they said they did a study of lucid dreaming with this, and a lot of their participants had their first ever lucid dream in the lab that night and what's amazing about some of this stuff is if you get to practice a physical skill in a lucid dream they improve on that skill in real life like what sort of things would you well they've been doing things like sort of skateboarding because you need to do something which is actually quite exciting otherwise you have a lucid dream you could be flying and you think, I'll just sit here hitting a piano key or something. That's not going to happen.

That's the sort of thing psychologists ask people to do, just hit a piano key. That's how imaginative we are. They've been saying things like, practice skateboarding. In real life, they get better at being a skateboarder. Amazing. Do we know why we dream

no but it doesn't stop us speculating so um there's lots and lots of thoughts about it so so part of it is to do with memory which which penny will know a great deal about um another part is to do a little on theory is that you are reliving events which are traumatic to some extent and you're knocking off the emotional edges of them and by repeating by repeating the event in a in a safe uh space and is that because i would say that that was not helpful to to to be reliving it well in a sense but it depends how quite how you're reliving it but but the more you experience something um under certain circumstances the less emotional that gets you're separating the memory if you like from the emotional side and that's one of the arguments my my favorite argument about dreams is that we're

actually solving problems is that we're actually solving problems is that we're thinking about events in our lives and we're trying to come up with certain ways of solving them and certainly people do come up with very creative solutions immediately after they've dreamt and there's some research supporting that so i suspect it doesn't have one purpose it probably has several and penny in terms of memory could you outline that theory that dreaming is associated with memory what imprinting yeah so we know that when we've learned something um the brain activity associated with that memory spontaneously occurs again during sleep so we call this replay but you could think of it as the brain just practicing something and

we know that that practicing is associated with strengthening memories integrating them together and protecting them against interference but basically memories are being activated again during sleep and so there's one idea that sometimes these reactivations, which are happening all the time when you're asleep, sometimes they come to consciousness and manifest as a dream. What is it when you dream something and then it happens the next day? My mother used to dream about disasters and we used to find it quite frightening. She would dream about them and then they would she wasn't involved in them

but can I just ask though it is definitely coincidence we should just clear this up it may or may not be no it is I'm telling you you can't see the future in your dreams

I know that because I know about the structure of space that's not the claim it know about the structure of space. That's not the same thing. It's always the structure of space, Tom. It's not the same thing. That wasn't the claim. The claim wasn't the psychic one. The claim was the merely matching of dream material to an event the following day, which may be coincidence if you were to be

a close-minded sceptic like some of us. And the other option is? The other option is, it's complicated, Brian, it's to do with quantum physics. You draw a line under that. No, actually, here's my problem. No, not actually.

It's not to do with quantum physics. No, it could be. Parallel universes. No. How can you say that? Why can't it be parallel universes when in another universe that dream didn't correspond? There must be loads of dreams and loads of universes.

Well, that would be coincidence, but it would be like saying that I drew 100 heads... Well, I tossed a coin and it came up heads 100 times. I've done that. That's just that. No, you haven't. No, I haven't. The other possibility is that we have lots of dreams and if an event happens the next day which matches one of them, it kicks off a memory of the dream.

The other possibility is that there's something out there which made you concerned about something, which could lead to a certain dream and then lead to the event. So there could be all sorts of explanations. It would be she would have dreamt it, she would tell us in the morning about this upsetting dream and then it would happen. So it's not like she dreamt it and then said,

we were all witness to this. But this is what I want to know, is how many times did this happen before you started saying to your mum, well, I'd ring the shipping company and tell them to go a different route? How did you know it was a ship? Oh, I'm so sorry, but I...

Brian, you don't know about my powers. It'll ruin your belief in the universe. Was it? Was it? Yeah. That was one of them. Yeah. But wasn't there a point of the number of times

that this happened that you would then go, I wonder if there's a way we can work out where? I've put the money on number seven. Yeah. At Roehampton or whatever. Did she ever give you the lottery numbers? No, she didn't believe in gambling. Well, for someone with magical powers,

that's quite a limiting belief, isn't it? Come on, Mum. This does feed into that idea. I suppose before the 50s, as you said, before the scientific investigation of dreams, there is a long history of attaching real i don't know import to these things totally i mean for some communities it was a way that the gods would speak to them other times if if you had a worrying dream it meant something was worrying was going to

happen in in your life and and of course freud is is attaching a great deal of importance to the meaning of them so from his perspective you have these kind of repressed thoughts anything to do with sex or aggression you repress our consciousness, and in dreams they bubble forward and they tell you a great deal about your sexual urges or whatever. So yeah, people have attached meaning to them, sometimes magical, sometimes religious. And to some extent, in terms of the Freudian approach, modern day psychology suggests there is something to that. Dreams are not meaningless in that sense. They're not random. They do have meaning for us. I'm a bit sceptical about them predicting the future, but there might be other explanations. I'm a lot sceptical. A bit.

I'm being polite, Brian. Isn't the truth of it, though, that more often than not, dreams are quite bland? We read about it, that way they are as you were saying perhaps there is this sense of rehearsal there is i mean i had last night my dream which had no masonry in it at all was i was with brian and uh we went to check in in in a hotel which we've done nothing separate rooms we've done we've done 70 tour dates together we've checked checked into 70 hotels. So all my dream was, I hope it doesn't go wrong next time when we check in and Brian says, we'll have to use this one room and I'm going to have the top bunk.

No, I mean, most dreams are fairly bland. So you wake people up and they just go, I was in the office and an invoice came in and so on. It's not very exciting. But they are pretty negative. They often reflect concerns and and worries and they could be quite dangerous places the murder rates in your dream is higher than any city in the world so they can be quite threatening places what um what's sleepwalking

because my brother used to come into our room and say lots of things about cakes and things your family i have to admit, this is becoming quite a gothic novel, isn't it, with a tinge of Stephen King's Carrie at the moment. A lot of us, yeah. So what's sleep? And we'd have a conversation. So he'd be asleep and he'd say,

they've left all the food in the garden, and I'd say, I don't think they have. And he said, they have, go and have a look. And then you'd say, are you you okay and then he'd just sort of but he was asleep so why could he have a so he could hear me but he was so I think sleep

walking and sleep talking and actually night terrors which are not bad dreams they're something else are all in the same category so it's a very weird state of consciousness where you're in non-REM actually but you also somehow in in kind of a waking state as well and so i used to get night terrors all the time so if you haven't had one you kind of wake up with your eyes open you scream out if you're sleeping next to somebody it wakes them up genuinely and then you having the night terror you're in deep sleep so you go straight back to sleep

and they're the ones with their heart beating. That's why they're called night terrors. So it's all the same thing, which is that normally in deep sleep and in dreaming, you're paralysed, you don't move around and hurt yourself, but there are certain, if you want to use the word disorders, where it all starts to get a little bit messed up. And one of the problems is that in those states, your pain receptors are quite minimal. So if you knock over use the word disorders, where it all starts to get a little bit messed up. And one of the problems is that in those states,

your pain receptors are quite minimal. So if you knock over a glass or something, you might walk over it and not realise. So it's important to get people in a sort of safe state. And if it is something like that, it's good not to get too close to them, because otherwise they might perceive you as the problem, particularly if it's a night terror.

Instead, you just sort of say their name very quietly from a distance and ask them what their pin number uh do we know um whether these phases of sleep uh dreams etc are limited to humans oh my cats my cats um go crazy when they're asleep yeah they look like they're dreaming they do they they go to catch they they literally play when they're asleep they like they're doing that with their legs and stuff like they're throwing a mouse around so would that would that be a dream and and i suppose the deeper question is whether it seems to be a an inevitable property a property of all brains or whether it's something uniquely human, these particular sleep patterns?

So sleep seems to be a property of every living organism. So everything that we've looked at, even amoeba, exhibits something that we could consider sleep. They don't have REM and non-REM because they don't have enough neurons. They don't have any. and non-REM because they don't have enough neurons. They don't have any.

But they exhibit a state where they sort of ball up. They don't move around. And if they're deprived of that by, for instance, shaking them, then they need more. So they need to get it. So we would consider that to be an equivalent to sleep in terms of rem and non-rem all warm-blooded animals have rem and non-rem sleep cold-blooded animals don't necessarily have rem would any animals have deep sleep apart from ones that hibernate because

isn't wouldn't it be like a survival a survival thing that if they just had loads of deep sleep, they could just be killed really easily? I know that what I'm saying makes sense. Because a lot of... So actually, hibernation is something that animals do to save energy, right? So they cool down their body temperature, they don't move, and they save energy in the winter when there's no food around and actually um fascinatingly hibernating animals actually warm up periodically so that means they're investing energy in order to obtain sleep

because when they're they're cool to a certain point their brains cannot exhibit the activity that they need to exhibit for point, their brains cannot exhibit the activity that they need to exhibit for sleep. So that's one of the really nice pieces of evidence that sleep is incredibly important. It's so important that an animal which is really trying to conserve energy in every way possible, hibernating,

will invest energy just to get sleep. That's a beautiful vision of the idea of a hedgehog waking up in the spring and desperately trying to remember the dream it had in November. So it seems what you're saying is we don't really know the reason for sleep or indeed dreams, but it appears to be absolutely fundamental because animals go to a lot of trouble.

And it's quite high risk, I suppose, going to sleep and being essentially unconscious, isn't it? But you might argue the a lot of trouble. And it's quite high risk, I suppose, going to sleep and being essentially unconscious, isn't it? But you might argue the opposite, of course. It's a way of keeping yourself safe at night when you'd be at risk of being attacked. But I suspect, I mean, it is incredibly important. And so I suspect there's not one reason for it.

I suspect there's several reasons. And that may be reflected in the different sorts of sleep, as you said. One perhaps is rejuvenative or regenerative or something like that and then there's the the memory aspect and so on so these are different things that happen exactly so i mean i would say um we we do know quite a lot about why sleep is important although i would be very cautious about saying we know everything um so there are different roles for it. We don't know why we dream.

I think with dreaming, we shouldn't forget, for me at least, that the relationship between dreaming and creativity, that notion of problem-solving, I mean, so many people have woken up from a dream with something fully formed in their head. So Paul McCartney with Yesterday, allegedly, Stephen King with The Plot of Misery, Robert Louis Stevenson, jekyll and hyde

uh was entirely written in the periodic table very which we're talking about next week actually right on the show so that that was dreamed famously wasn't the pattern that's right so if we're doing something and it was robert low stevenson um he was sort of getting a whole thing with jekyll and hyde in his head and his wife sort of saw him thrashing around the dream and woke him up before the end of the story so he had to write the end of the story awake um and it doesn't come from his dream which is why the end is rubbish so there's one about keith richards you know that one where he was i think it was like the early mid 60s he was on tour and apparently he always he put his guitar right next to him in the bed,

and he used to keep a little recording device as well. And he went to sleep, and he woke up the next morning, he went, oh, no, I must have accidentally knocked the record button, because of the whole thing. And then he rewound it and played it, and apparently he sleep-played for the first time the opening bars of Satisfaction. He said, I basically heard one minute of this new song,

and the rest of it was just me snoring. That's incredible. That is's incredible that is amazing that is amazing and so the idea is the same applies to everyday lives we've all got problems and worries and concerns and our brain is kind of working on them and if you wake people up from some of those early rem dreams they're pretty negative dreams emotionally as you go through the night they get a bit more positive so it's possible it's a bit like an inner therapist that's working away on our problems hopefully coming up with some kind of solution by the morning having heard this now and you mentioned before at the beginning of the show the fact that you've had uh you know kind of some some dreams you have obviously are very dark and dreams you don't like do you feel having heard these things about dreams now and the dreamscape

when we're asleep do you feel more comfortable now no i feel much worse about myself no yeah because they've they've i mean apparently come from somewhere and they mean something where i was consoling myself with the fact that they were literally nothing to do with me but but they were weren't they yeah it turns out they're a very deep reflection of your inner character and also they're recurring as well. If you have a recurring bad dream, there's a great thing called imagery rehearsal therapy. So during the day, you just imagine the same dream but with a happier ending.

As it were. Get your trousers on! You started it with those two turrets. I think you'll find you're definitely the Freudian out of this panel. What you could do is rehearse the dream with a more positive ending. And it's good with children as well. So if you have a child who's having a recurring nightmare, say they're being traced by a dragon or something,

you say, well, actually, maybe it's a friendly dragon, it just wants to be your friend and it's a lonely dragon and so on. Now you do that a few times during the day, it can affect your dream if it's a recurring nightmare at night. It's pretty good stuff, so it's very simple. Bridget, the dragon's friendly. It's a friendly dragon.

It's a friendly dragon, Robin. So you could try having some really pleasant scent wafted occasionally through your bedroom pleasant scent yes because there's been work showing that if people smell a pleasant scent that they have positive dreams and if they smell an unpleasant scent then they have negative dreams so you could try it but don't just have it constantly because you'll habituate and won't have any effect at all okay OK, so nice smells. Occasionally.

What I'd say, Bridget, is I've been seeing a therapist and I've found it very useful. Obviously, it's a therapist employed by English Heritage, but nevertheless, we can still give it a go. Richard, how do we know this whole episode hasn't just been a dream? Oh, we don't know. We don't know. Of course, the whole thing could be a dream. But if so, it's been a fairly long dream.

And not one that I would have chosen. So that's probably the best evidence. Anyway, so we asked the audience a question. We'll just go straight to that. We were going to ask the question, if Brian Cox appeared in your dream, what would you like to see him doing? But we saw some of the answers.

And they all said data analysis. So instead, we have asked the audience, tonight's show is about the science of dreaming. Which one of your dreams would you most like to come true? To fly among the stars like Captain Marvel with Brian Cox narrating the adventure. Of course, you do realise that you're not able to fly because that

would break the laws of physics. Why did you say that? I'm dead. It's perfectly possible to fly amongst the stars. There's nothing wrong with that. Have you seen Captain Marvel? Have you seen the way that she flies between stars? Oh, like Captain Marvel? Yes. No, there would be issues, wouldn't there, in terms of the structure of space-time or whatever?

I've got some. I've got one from Leo B. That random one where I get arrested for saying that discs four and five of Queen's Greatest Hits are terrible. I didn't even know there were discs four and five of Queen's Greatest Hits. Wow.

What's on them? That's one of the most random... The idea of turning the order is going, what's on them? I did a book event up in Keswick a while ago, and the first question I got after I did my talk, this woman went, my daughter doesn't want me to ask this, but I want to ask it, and her daughter was going, oh, God, Mum. She said, I just wanted to know this.

Someone in the queue was talking about the thinking man's crumpet, and we can't remember her name. What was it? And I said, oh, it's Joan Bakewell. She said, thank you. And all I hoped was that the other five hands would go, oh, I was going to ask that as well. This is really, this is quite strange from Eden.

It's a balloon-making machine. It puts an object in, and it comes out as a balloon. And then. It puts an object in and it comes out as a balloon. And then in brackets, including my sister. This is from Ivan. Ivan says, The dream where I become a panel member on the Infinite Monkey Cage and replace Brian Cox as the sexiest physicist. There's not a lot of competition there.

Oh, Martin Jarvis. My dream did come true, and I married her. That's where we should stop, I think. So, thank you very much to our panel, who have been Professor Richard Wiseman, Professor Penny Lewis, and Professor Bridget Christie. We've had to change what the subject of next week's show is, because we actually had a thing from one of the executives at the BBC

who said, look, it's all very well popularising science, but the trouble is a lot of science doesn't seem to be very edible, and that's what people like. So could you do something with more recipes in? So we are going to do an ingredients special next week in which we will be celebrating the 150th anniversary of the periodic table and making something out of all of it. Just seeing what happens.

Anyway, that's next week. Thank you again for listening. Bye-bye. Thank you for listening to the Infinite Monkey Cage. There are many other Infinite Monkey Cage podcasts downloadable on BBC Sounds and also many other podcasts that aren't the Infinite Monkey Cage on BBC Sounds.

They're not an infinite number. I mean, there is a universe where all of the BBC Sounds podcasts are the Infinite Monkey Cage, but there are others which are all the life scientific, and that's when the battle really begins. Yeah, I don't think... You don't think he's a real physicist? He looks like a real physicist.

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