Sleep

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Speaker 1 Hey,

Speaker 1 You know, which is like very early days of our show,

Speaker 1 about a fundamental mystery that now, like almost 20 years later,

Speaker 1 is still just as fundamental and just as mysterious as it was then.

Speaker 1 It is a fundamental mystery that takes up about a third of your life and actually probably

Speaker 1 more considering how much much you crave it when you can't get it, but then paradoxically put it off when you can.

Speaker 1 Anyway, I'm not going to say anymore because I don't want to step on the original episode intro, which is just adorable.

Speaker 1 So here you are, drift off with our emeritus hosts, Jad and Robert.

Speaker 3 Wait, you're listening.

Speaker 3 You're listening

Speaker 3 to Radio Lab

Speaker 3 from

Speaker 1 WNYC.

Speaker 6 I just thought I'd see if I can get the sound of baby sleeping.

Speaker 7 This is Radio Lab. Today's program is about sleep.

Speaker 7 I don't have to tell you how good sleep is.

Speaker 8 You do it yourself.

Speaker 9 Every night.

Speaker 7 Or you try.

Speaker 7 And how wonderful when it actually works, when you can close your eyes and forget the day and just drift off into oblivion, like a little baby.

Speaker 7 But let's suppose that you are a little baby, this little baby, and you grow up to become a scientist, like one of the scientists we'll hear from in this program, and you decide to ask what should be the dumbest question ever.

Speaker 7 Why do we sleep?

Speaker 10 Not just us. Well, pretty much everything sleeps.

Speaker 11 As far as we know, all mammals do it.

Speaker 12 All birds. Bees, locusts, cockroaches, crayfish, reptiles, insects, scorpions.

Speaker 13 Everything that's been studied has something that looks like sleep.

Speaker 14 It's a mystery.

Speaker 15 Most things we sort of know what they are for and also how they work. But sleep is really in your face.
I mean, everybody does it. You do it from the cradle to the grave.

Speaker 15 You can't help doing it because if you try to stay awake, you know, at some point it's irrepressible.

Speaker 14 And we don't know why?

Speaker 15 That's a shameful state of affairs. How can you be a scientist in the 21st century and not know the answer to that?

Speaker 17 There you go. Okay.

Speaker 19 That's a pretty good way to begin, no?

Speaker 14 With shame? Yeah, yeah.

Speaker 21 Today on Radio Lab, we're going to try to correct this shameful state of affairs when it comes to the subject of sleep.

Speaker 7 We'll talk with people who can help us understand what it's for, why we do it, and what happens when we don't. I'm Robert Krulwich.
I'm Jad Abumran.

Speaker 14 Stay with us.

Speaker 7 For centuries, people thought that sleep was kind of the opposite of being awake.

Speaker 19 It's reasonable, one would think.

Speaker 7 Sure, because during the day, you're doing all these things, you're having all these thoughts and feelings. At night, you just lie there.
Very, very still.

Speaker 7 In fact, like sometimes a bomb could go off and you wouldn't wake up.

Speaker 10 I can hardly wake up even in a fire.

Speaker 18 I don't know why.

Speaker 10 No, I'm a really heavy sleeper.

Speaker 21 I am a very, very heavy sleeper.

Speaker 7 The point is, if all you've got are your eyes to go on, sleep can seem like being, well, like...

Speaker 5 Like being off.

Speaker 7 Yeah, like offness.

Speaker 17 Right.

Speaker 10 Or worse. Well, both Shakespeare and Cervantes referred to sleep as death.

Speaker 7 That's Dr. Carlos Schenk.
He wrote a great book about sleep called Paradox Lost.

Speaker 25 We go to bed every night, we die every night, and then we wake up in the morning and we're alive again. And that was the prevailing theory for centuries.

Speaker 7 For Dr. Schenk, the awakening to just how wrong Shakespeare and Cervantes were about sleep came one day while he was sitting in class for med school.

Speaker 7 My first year at medical school, this was back in 1972.

Speaker 25 We had an emeritus professor who actually was a Nobel Prize winner, Dr.

Speaker 30 Eccles,

Speaker 7 Sir John Carew Eccles from the Here's what happened: this esteemed lecturer walks into class, pops a cassette into the tape deck, hits play, and out comes this sound.

Speaker 25 Well, the sound was

Speaker 18 or

Speaker 31 wait a second.

Speaker 25 Let me get it right. Oh, here we go.

Speaker 25 And multiply this by 100.

Speaker 7 This, the professor announced, is the sound of a cat's brain while asleep.

Speaker 18 My god!

Speaker 32 Shank almost fell out of his seat. This is the brain during sleep?

Speaker 31 Making these really rapid, high-pitched, multiple sounds. That just blew us away, wasn't it?

Speaker 32 Clearly, while that cat was curled up in its little kitty basket, its brain was very, very alive.

Speaker 7 Much more than anyone expected. And this is still a weird revelation.
Like, take my cat, Sammy. Sammy.
Alright, this was the sound of my cat, Sammy, sleeping.

Speaker 7 To think that while Sammy is sitting on my lap, totally out,

Speaker 7 there's a circus happening in his brain.

Speaker 14 What's going on in there?

Speaker 7 If you can imagine back in the 70s, this was a paradigm shift. People were suddenly like, oh my god, we're going to figure out anything about sleep.

Speaker 7 We have to ask the brain.

Speaker 12 And then this is the room where we do all of our surgeries.

Speaker 9 And luckily,

Speaker 7 that's easily done.

Speaker 7 if you're willing to get your hands dirty.

Speaker 12 Okay, so the first step is you have to make an incision on top of the animal's head. When you've done that, we drill holes through the animal's skeleton.

Speaker 12 And then you insert your electrode, your skull.

Speaker 17 Then you've got

Speaker 7 to get a little window into their brain. You could see right there on the screen.
You could see the brain waves.

Speaker 30 Are you out of your mind?

Speaker 22 Did you just put a hole into a kitten's head?

Speaker 7 No, that wasn't my cat. Come on.

Speaker 35 So what was it we were doing there?

Speaker 7 What you just heard was

Speaker 7 a mock surgery to an iguana, actually.

Speaker 30 Even an iguana, I mean, it's not a nice thing.

Speaker 7 Look, look, look, look. The animal was not harmed.

Speaker 12 Within 20 minutes of coming out of the anesthetic, the animal is moving around, it's eating, it's climbing, and it's basking.

Speaker 12 It might seem like a rather invasive procedure, but in actuality, it's not too bad at all.

Speaker 7 Yeah, and that, by the way, is John Leskew.

Speaker 13 He's a graduate student at the ecology department.

Speaker 12 At Indiana State University, which is where we are.

Speaker 7 John gave our reporter Kara Ohler

Speaker 26 a tour of the lab.

Speaker 12 There are big boys here, and they all have nice hats.

Speaker 7 Show the iguanas.

Speaker 36 These guys are a little frightening to me. They're pretty huge.

Speaker 7 They're like four feet long, head to tail.

Speaker 38 Oh, I didn't know that.

Speaker 7 I mean, they look like baby alligators.

Speaker 7 And John measures their brain waves at night to see what happens in their head as they sleep. In a way, it's a continuation of that cat experiment that Dr.
Schenk just told us about.

Speaker 7 Except, what they're looking for is much more peculiar than could ever happen in a cat or in us.

Speaker 34 What is that?

Speaker 7 Let me put it to you as a puzzle.

Speaker 7 Forget iguanas. Dolphins, right?

Speaker 14 Dolphins. Yep.

Speaker 7 How is it that a dolphin in the ocean, or even say the dolphins that you might find at Six Flags in New Jersey,

Speaker 7 they have two?

Speaker 6 Cody is our 10-year-old Atlantic bottomless dolphin.

Speaker 39 His buddy Avalon is 12 years old.

Speaker 7 And that's our trainer, Megan Tutera. Viramitra is holding the mic.
Anyhow, here's the puzzle. We asked Megan about this.

Speaker 7 How is it that her two dolphins, Cody and Avalon, can successfully sleep, given the inherent challenges of being a dolphin?

Speaker 40 I don't, I don't, what do you mean by the challenges of a dolphin?

Speaker 7 Well, they have significant challenges, my friend.

Speaker 13 First, they've got to breathe. They're not.

Speaker 39 They're conscious breathers. They're not unconscious breathers.
So they have to think about breathing.

Speaker 7 Making matters worse, dolphins are not fish. So they have to breathe air, which means they have to constantly, consciously come up to the surface to breathe air every few minutes.

Speaker 7 So you can imagine what would happen if they decided to go unconscious for a while.

Speaker 41 They would drown. Right.

Speaker 7 And yet they do manage to sleep a lot.

Speaker 30 How long?

Speaker 7 Eight hours a day.

Speaker 17 Like airing.

Speaker 7 Yeah, eight hours. But how?

Speaker 36 That's the puzzle.

Speaker 39 What happens is they do what we call logging. It's when they rest on the surface of the water.
You know, when a log floats down a river, it just floats. That's exactly what they look like.

Speaker 39 And they rest half their brain at a time.

Speaker 32 Half their brain is asleep.

Speaker 39 Half their brain is asleep at a time.

Speaker 7 That is nature's solution. To cut the dolphin brain in half.

Speaker 30 You mean literally in half?

Speaker 7 Literally in half. So that one half can snooze while the other half keeps the dolphin swimming and surfacing.

Speaker 5 Wow.

Speaker 7 Just enough to breathe. From the outside, you can't really tell what's happening.
It just looks like the dolphin is sort of awake, but a little out of it.

Speaker 39 So it's almost like the state of when you're falling asleep, but if something happened, you'd wake right up. So they're in that state all the time.

Speaker 13 This sort of guy can be characterized as groggy.

Speaker 7 That's Steve Lima. He runs one of the labs back at Indiana.

Speaker 13 They're sort of awake and they're sort of asleep, and it's just a way of staying awake enough.

Speaker 7 And again, it's easy to miss, but if you look inside that groggy dolphin's brain, what the brain waves are doing is exquisitely obvious. It's clear as they six-year-old can figure it out.

Speaker 13 One half of the brain has these beautiful, slow waves, like a sine curve.

Speaker 13 And the other one's just

Speaker 13 jagging all over the place.

Speaker 13 Oh, those are beautiful.

Speaker 42 Wow, that is amazing.

Speaker 7 Yeah, it's called unihemispheric sleep. That's what the guys at Indiana State are really interested in.
Because, and here's the next surprise: it seems to go way beyond dolphins. Oh, yeah, yeah.

Speaker 12 Aquatic mammals like whales, seals, and sea lions.

Speaker 7 John says that all the marine mammals that have been studied seem to do it too.

Speaker 12 Recently, walruses, they're all found to engage in unihemispheric sleep as well.

Speaker 7 And now, the Indiana team, led by

Speaker 43 this guy.

Speaker 11 I'm Charles Amlaner, chair of the Department of Ecology and Organismal Biology.

Speaker 7 They have found this weird split-brain behavior in creatures of the air.

Speaker 11 Let me just back up a little bit and describe this experiment.

Speaker 7 Charlie and a student had been at the park one day, and they noticed something.

Speaker 8 We observed that ducks

Speaker 8 sometimes will get together into groups.

Speaker 7 Like on a log. Four ducks will get together and snooze in a neat little line.

Speaker 8 And the birds that were sitting in the middle of that line tended to be sleeping with both eyes closed. The birds that were sitting on the outside of that row tended to look a little bit more wary.

Speaker 7 The inevitable question

Speaker 7 led to a very simple experiment.

Speaker 43 We put four birds in a row.

Speaker 7 Four mallard ducks, this time in the lab.

Speaker 7 And they watched them sleep.

Speaker 8 The two birds in the center of this row slept with both eyes closed.

Speaker 14 The birds on the outer edges, both left and right, slept with one eye closed and one eye opened.

Speaker 8 One more time.

Speaker 14 Slept with one eye closed and one eye opened.

Speaker 7 It's just like in that song.

Speaker 7 Do you know that Metallica song?

Speaker 17 I missed it.

Speaker 30 I missed it. It was a good one.

Speaker 22 But I knew they were all botanists.

Speaker 7 It's true. You know, no one knows this, but that song is really about adaptive sleeping behavior in ducks.

Speaker 8 The outer eye, the eye that was faced away from the group, the eye that was facing towards where potential predators might come from, that stayed open.

Speaker 7 At this point, Charlie had a pretty good idea of what was going on because he knew that inside bird brains, each eye is attached to the opposite hemisphere.

Speaker 8 The left eye is attached to the right hemisphere.

Speaker 14 The right eye is attached to the left hemisphere.

Speaker 7 So his team implanted some electrodes to measure what the duck brains were doing and

Speaker 18 voila.

Speaker 7 Like the dolphins, the ducks, too, were sleeping one half of their brain at a time.

Speaker 45 The bird could simultaneously sleep and be awake.

Speaker 7 Not only that, here's the cool part. After a few hours.

Speaker 43 What happened was that the birds that were on the outer edge then would rotate, stand up, turn around, 180 degrees, and then sit back down.

Speaker 14 And the other eye would then get some sleep, and consequently, the opposite hemisphere would get some sleep.

Speaker 13 When we saw that, we said, oh yeah, this is...

Speaker 18 That's good.

Speaker 7 Good, because right there in the ducks was a perfect illustration of what these guys think it's all about. You've got to sleep for whatever reason, right? But sleep is dangerous.

Speaker 7 Danger, danger, danger. That's the headline.
For dolphins, the main danger is drowning. Danger, danger.
You know, yeah, for ducks, getting eaten, exactly. Danger, danger.
Ducks have to sleep.

Speaker 17 But how can they? Danger.

Speaker 7 When lurking in the darkness are foxes and wolves and a hundred other eaters of ducks.

Speaker 32 Do you like snakes?

Speaker 32 I don't know.

Speaker 32 Not really.

Speaker 36 I don't dislike snakes.

Speaker 32 He's a good man. He's a good man.

Speaker 7 In another nifty experiment, John took the resident snake Monty. This is

Speaker 7 Monty.

Speaker 12 Hi. Big snake.
He is what, about a four-foot-long python. Mm-hmm.
And at night, you're so cute.

Speaker 7 John brought Monty, the python, into the room where his iguanas sleep.

Speaker 12 And he terrifies that really.

Speaker 7 Well, I mean, Monty was in a cage, so he couldn't really hurt the iguanas. But as soon as that snake appeared, all the lizards popped one eye open.

Speaker 17 I bet they did.

Speaker 7 And they trained that open eye right on Monty the snake.

Speaker 13 Put a big snake in the room and they'll watch it with one eye all night.

Speaker 8 That's Steve Lima again.

Speaker 13 They don't like these snakes, that's for sure. And they remove the snake from the room the next day, and they're still looking for it the next night or two.

Speaker 7 So they keep one eye trained on that door for a few more?

Speaker 9 About two or three days.

Speaker 13 They go back to regular sleep.

Speaker 19 So, what does this all mean?

Speaker 7 Well, think about this. Okay, all the sea mammals, they do it.
Right. Well, at least the ones that have been studied.
All the flying creatures, they do it. The reptiles seem to do it too.

Speaker 7 Who does that leave?

Speaker 46 You mean who's left not sleeping with half a brain on and the other half a brain off?

Speaker 38 Yeah.

Speaker 18 us

Speaker 7 we may be the strange ones.

Speaker 12 Well, it is sort of strange in that terrestrial mammals can't do it. Terrestrial mammals just for some reason have lost the ability to do this.

Speaker 7 Not all mammals, says John, terrestrial mammals, the ones that live on land.

Speaker 7 And here's his theory. Sometime long ago, our scaly ancestor wandered up onto land and thought, I think I'll dig a hole.
Yeah, I'm gonna dig a hole.

Speaker 7 And the hole was dark, and it was safe. And for the first time in millions of years of evolution, that little creature closed both eyes.

Speaker 7 And so we lost it.

Speaker 7 Totally speculative theory, of course. But the basic idea, though, is if you are protected and safe, you can afford to close both eyes, conk out completely.

Speaker 7 And that simple idea of safety, that explains, well, these guys think almost everything. Where you sleep, how you sleep, how long you sleep.
It all boils down to two words.

Speaker 13 Predation risk.

Speaker 12 Predation risk.

Speaker 8 Predation risk.

Speaker 7 Which is really just a fancy way of saying it.

Speaker 13 Generally speaking, just your risk of being killed.

Speaker 7 Your risk of being eaten. No.

Speaker 7 What does this have to do with us?

Speaker 7 Here we are, top of the food chain in our warm beds.

Speaker 8 Nice warm bed.

Speaker 17 Locked door.

Speaker 14 A locked door.

Speaker 8 Covers.

Speaker 7 Maybe a nice neighborhood.

Speaker 8 A good police force looking after you at nighttime, and you live in a country that has a very secure living environment.

Speaker 7 You would think that this whole predation risk idea has nothing to do with us.

Speaker 12 Well?

Speaker 12 Well, there's a few studies that have looked at, say, sleep patterns where people are sleeping in novel environments.

Speaker 29 What's a novel environment?

Speaker 19 What does he mean?

Speaker 17 Well, like a hotel. Oh.

Speaker 7 That first night at a hotel, why is it no one could sleep well that first night at a hotel?

Speaker 12 On your first night of sleeping in a hotel room, you generally have less REM sleep and less deep slow wave sleep relative to sleeping in your house.

Speaker 13 I suffer from that myself. I don't sleep well in hotel rooms, especially if it's just one night per place or something.

Speaker 9 My sleep is terrible.

Speaker 12 There are some folk that actually hypothesize there are certain uh predator uh relays in the brain, danger, danger, danger, danger, and that these circuits remain active at all times.

Speaker 7 Now what if that's true that

Speaker 7 we all have buried deep in our reptile brain a sort of predator alert system?

Speaker 7 Perhaps in some of us

Speaker 43 it's a little too sensitive.

Speaker 7 Okay we're in the sleep lab at the Minnesota Regional Sleep Disorder Center, mission control we call it.

Speaker 27 We're viewing the typical sleep terror episode. This little girl who is five years old would engage in these sleep terror episodes every single night.

Speaker 7 That's Dr. Carlos Schenk, who we heard from before.
We're in Minnesota now at the Hennepin County Sleep Center

Speaker 7 where he works. We're standing in front of a grainy black and white video of a little girl in her PJs screaming.

Speaker 7 Dr. Schenk discovered an odd category of sleep disorders called parasomnias, which is why we came to talk to him.
Para means around. Somnio means sleep.
Around sleep.

Speaker 7 This might be the human analog to the ducks. People whose brains never quite shut off completely during sleep.

Speaker 44 Well, this guy is interesting. He has seizures.
No, no, no, he doesn't.

Speaker 29 Wait a second.

Speaker 7 He showed us tape after tape.

Speaker 27 We're viewing a man who we very affectionately call Santa Claus.

Speaker 7 On the screen, a large guy thrashes back and forth.

Speaker 27 His legs are moving, he's going back and forth with his side to his back.

Speaker 7 And then suddenly he starts to

Speaker 32 Is this real?

Speaker 7 Yeah, this guy is in and out of sleep. He has no idea what he's doing.
One of the interesting things Dr.

Speaker 7 Schneck noticed when he first began to diagnose parasomnias in the early 80s is that while they were in that kind of liminal space around sleep, a huge percentage of the patients would have these visceral dreams of being attacked.

Speaker 25 The common theme is a menace is posed from nowhere, coming out of nowhere. It's an immediate threat that you just can't ignore.
Let's put it that way.

Speaker 16 You have to either fight it or run away from it.

Speaker 49 The dreams can be very violent.

Speaker 7 This is Martin Sabell, age 88. He's another of Dr.
Schenck's patients.

Speaker 49 I remember someone coming up the stairway.

Speaker 7 In Martin's case, the attackers never had a face. Sometimes it was a bear.

Speaker 49 And I was going to fight with him.

Speaker 50 He'd yell at him, get out of here!

Speaker 7 That's Martin's wife, Gertrude.

Speaker 19 Scram!

Speaker 50 He was always trying to protect me.

Speaker 49 Yeah, I'd have black and blue bruises on my arms and hands because I was hitting the headboard.

Speaker 25 Not infrequently, the man is dreaming in bed with his wife that he is fighting to defend her from an attacker when, in fact, he's beating her up.

Speaker 50 One night I was sleeping, and all of a sudden, he's got his hands tightly around my throat.

Speaker 50 I'm petrified. Quit, Mart.

Speaker 49 You're dreaming. You're hurting me.
She says, Martin, you're dreaming.

Speaker 7 Gertrude and Martin Zabel are still married, believe it or not, after 57 years, though she did force him to sell his guns.

Speaker 50 He has never been happy about that.

Speaker 17 Well, they were quite valuable.

Speaker 51 So you're suggesting then that all these people and the iguanas and the ducks and the dolphins all have a portion of their brain which is weary in the night.

Speaker 7 That's what I'm hinting at. I don't want to go any stronger than hint at, but there seems to be...

Speaker 7 Something in us that's always watching out, always wary.

Speaker 21 Bottom line here, though, is that sleep for all creatures is a dangerous thing, and a few unfortunate people are still awake to that fact.

Speaker 7 That's right.

Speaker 7 Before we go to break, I just want to thank Ann Hepperman for her excellent reporting in Minnesota and also before her Kara Ohler and to remind you to stay with us because we're going to turn our attention shortly from danger to deprivation.

Speaker 7 Radiolab will continue in a moment.

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Speaker 55 It's 1972. A young British family is attempting to sail around the world when disaster strikes.
Their boat is hit by killer whales and it sinks in seconds.

Speaker 55 All they have left is a life raft and each other. This is the true story of the Robertson family and their fight to survive.
Hosted by me, Becky Milligan.

Speaker 55 Listen to Adrift, an Apple original podcast produced by Blanchard House. Follow and listen on Apple podcasts.

Speaker 7 This is Radio Lab.

Speaker 9 You are Robert Krowich.

Speaker 41 Robert Krowich is my name.

Speaker 15 And you're...

Speaker 7 I'm Jad Abu Marad. And today our topic on Radio Lab is sleep.

Speaker 34 It is something that all of us do. We can't help but do it.

Speaker 21 It's dangerous to do.

Speaker 26 It's so good.

Speaker 38 And it's universal.

Speaker 13 Think about it. You know, sleep is dangerous.
And if sleep could have been circumvented in some way, natural selection probably would have found a way to do it.

Speaker 7 That's Steve Lima again from Indiana State University.

Speaker 13 Because

Speaker 13 it would be such a great idea to not sleep.

Speaker 7 Don't I know it? But there are times when you just can't sleep. Right.
Maybe you're one of the 35 million Americans I am who has chronic insomnia.

Speaker 7 You just can't sleep. You don't know why, it just doesn't happen.
Or maybe you do it to yourself and you pull all-nighters for school, or you have to drive long distances.

Speaker 7 Or, and here's what we want to turn our attention to next: maybe it is done to you.

Speaker 7 That's the case with producer Hannah Palin. She kept this audio diary of her own experiment with sleep deprivation.

Speaker 7 She has an 18-month-old son.

Speaker 6 It's 2.54 for the record.

Speaker 6 Today was my first day back at work.

Speaker 6 We were discussing budgets.

Speaker 18 I just

Speaker 6 I just I couldn't even articulate

Speaker 6 what it was that I was seeing on the computer screen and try to communicate that to the curator that I work for. for.

Speaker 6 The words didn't come

Speaker 6 lie down on me.

Speaker 6 Instead of saying,

Speaker 6 well, Nicolette, I believe that that choice was made because no, no, all that came out was like

Speaker 6 honey

Speaker 6 buckets. I mean, nothing, nothing would come out.
There's just no brain cells really. Darn.

Speaker 6 I almost had him asleep there.

Speaker 6 So anyway, uh, that was my first day day back at work.

Speaker 6 2:47.

Speaker 18 Dominic will not sleep.

Speaker 18 I don't know why.

Speaker 6 And I'm trying to get him to sleep and kind of at my woods end.

Speaker 18 Oh, God, this just sucks.

Speaker 18 Totally sucks.

Speaker 6 Here's the funny thing. Everybody has a theory.
And I was talking to my sister-in-law tonight, and her theory is that he's not getting enough milk because milk has some

Speaker 6 agent in it that would help him sleep. And he doesn't like milk, it's true.
Other people say, Oh, if you just would exercise him, if he just gets fresh air and exercise, he'll sleep all night.

Speaker 6 If you just let him cry, he would sleep all night. If you just would do whatever it is we're not doing, he would sleep all night.

Speaker 6 And there's this feeling like

Speaker 6 there's a feeling like I am doing it all wrong and that I'm a failure as a parent.

Speaker 6 I don't know how to do this.

Speaker 57 Come here, sweetie. Come here, come on, come on, come on, come on.
Just hang out on me.

Speaker 6 So anyway, I needed to record just one one thing really quickly, and that is that yesterday and today I've been struck by these

Speaker 7 I've been struck by these waves of

Speaker 6 satisfaction and delight with being alive in this amazing landscape with

Speaker 17 a funny kid

Speaker 6 and beautiful mountains and water and I don't know, maybe it's just getting a little more sleep in the last couple of days.

Speaker 18 that.

Speaker 6 But I suddenly feel like, wow, I'm so lucky.

Speaker 6 Okay, I've got to take my kid to play now.

Speaker 18 Here we go.

Speaker 6 Did you know the Muffin Man?

Speaker 18 The Muffin Man?

Speaker 6 Okay, that whole I'm loving life.

Speaker 6 Yeah, that's all gone now.

Speaker 6 And it's pretty much because Dominic won't take a nap.

Speaker 6 We came home from the beach, which I thought would wear him out.

Speaker 6 Then we sat down and read some stories, which for some reason. And I realized that an element to the sleep deprivation, and an element to this whole thing,

Speaker 6 is that

Speaker 18 I get angry

Speaker 6 from having my own needs subverted to the needs of this little tiny person,

Speaker 6 which, when you're not sleep-deprived, is not a big deal.

Speaker 7 I tired.

Speaker 18 I'm tired.

Speaker 6 I don't want to wish a minute of Dominic's childhood away because it's so precious to me.

Speaker 18 But damn.

Speaker 18 I am looking forward

Speaker 18 to

Speaker 6 that moment when I'm able to say, honey, time to go to sleep. And he does it.

Speaker 6 Tired. No.

Speaker 6 Not tired.

Speaker 6 Just make up.

Speaker 6 Close your eyes, bug.

Speaker 6 Close your eyes. Here's my personal take on what it's like to be sleepy.

Speaker 6 And to crave sleep as much as you crave water or breath.

Speaker 6 I crave it.

Speaker 6 Thanks to Hannah Palin.

Speaker 7 And her son, Dominic, and her husband, Steve.

Speaker 9 I know.

Speaker 17 Poor Hannah.

Speaker 41 But there is a science question lurking in the background, which is when, you know, when Hannah was so tired, why does she feel that way?

Speaker 30 You know, what?

Speaker 7 Because

Speaker 7 she hasn't been sleeping.

Speaker 56 Well, yeah, but what makes her...

Speaker 42 You know, what is the essence of tiredness?

Speaker 7 Lack of sleep. Hello.

Speaker 52 No, chemically, I'm asking you.

Speaker 30 Chemically,

Speaker 56 what is happening to her?

Speaker 42 If you were way down in her cells, could you see something tired-like going on?

Speaker 38 That's a good question.

Speaker 46 I'm glad you think so, because I know a guy who has a theory about this.

Speaker 32 Did you see Tiger yesterday?

Speaker 33 Tiger Reed. He's just unbelievable.

Speaker 32 He had the best round of anybody. I mean, the guy is unbelievable.

Speaker 58 This is Dr. Alan Pack.
And in addition to being a rabid golf fan, he's also a rabid...

Speaker 5 Can you be a rabid biologist?

Speaker 17 Sure.

Speaker 60 At the University of Pennsylvania, he's been looking at sleep down at the cellular level.

Speaker 48 And one thing that he's found over and over and over.

Speaker 45 And that's been shown in mouse, it's

Speaker 51 is that inside certain cells in all those different animals, when they're sleep deprived.

Speaker 45 Essentially, what happens is you don't get proteins properly folded.

Speaker 18 Excuse me?

Speaker 7 Proteins properly folded?

Speaker 45 A phenomenon called the unfolded protein response.

Speaker 7 What on earth does that mean? Is that a good thing or a bad thing?

Speaker 23 You're asking why do you need proteins to properly fold?

Speaker 7 Yeah, I guess that's what I'm asking.

Speaker 52 Well, you're made of proteins.

Speaker 58 Proteins are the essence of you.

Speaker 48 So if your proteins are misshapen, if they're not folded properly.

Speaker 45 If you don't fold the proteins properly, they don't have the right three-dimensional structure. And as a result, they start accumulating inside the cell.

Speaker 45 And then these different unfolded proteins can aggregate together and form clumps.

Speaker 18 Clumps.

Speaker 45 inside the cell and essentially clog it up. And it's really quite toxic to cells.

Speaker 56 Clumpiness equals tiredness, it would be his formula.

Speaker 51 Remember when Hannah was so

Speaker 59 exhausted? Yeah.

Speaker 18 Oh, God, this just sucks.

Speaker 46 Well, because she hasn't slept much,

Speaker 34 inside her cells, lots of these valuable little proteins have not folded properly.

Speaker 58 That, he thinks, is the consequence of not having enough sleep.

Speaker 21 So maybe what's going on is the cells can't do their business quite as well, and things start to break down. And that adds up across the whole of your body to a feeling of

Speaker 21 but when she gets to sleep, remember when she's so happy?

Speaker 6 Yeah, I suddenly feel like, wow.

Speaker 10 Because of the sleep.

Speaker 43 I'm so lucky.

Speaker 51 A group of cleaner-uppers have gone through her cells, removed the toxic and misshapen proteins so that

Speaker 20 in effect, sleep is the best housemaid you've ever had in the hotel of you.

Speaker 21 And this idea, the idea of sleep as a cleaner-upper, might even explain one of the most basic things about us as humans.

Speaker 17 How we learn.

Speaker 21 That's the notion of Dr.

Speaker 34 Giulio Tononi.

Speaker 6 Testing, testing, testing, testing.

Speaker 21 My producer Ellen Horn and I went to visit him at his offices in Madison, Wisconsin.

Speaker 44 What are we expecting? What does he look like?

Speaker 14 We don't know what he looks like. Football player.

Speaker 29 A football player.

Speaker 6 But like a quarterback or tight end, not like a

Speaker 29 linebacker.

Speaker 21 So big, but not overwhelming.

Speaker 57 Yes.

Speaker 61 How do you even know that?

Speaker 6 Website.

Speaker 36 See, but I was totally totally wrong.

Speaker 18 Since we are totally wrong.

Speaker 30 Now, to be fair,

Speaker 58 he is a very attractive guy. He has sandy blonde hair and glasses.

Speaker 60 So he's actually more of the sensitive guy intellectual than a linebacker.

Speaker 15 Introduce yourself. I'm Julio Tononi.
I am a professor of psychiatry here at the University of Wisconsin-Madison.

Speaker 21 But when it comes to the subject of sleep, which is his specialty, he takes sleep very seriously.

Speaker 24 What got you in sleep?

Speaker 15 Sleep is the annihilation of consciousness. So it's a terrible time in which everything disappears.
the universe and yourself with it.

Speaker 15 I think if people didn't sleep and didn't have the unconsciousness of sleep, they possibly wouldn't even realize that consciousness is an enormous gift.

Speaker 52 So being awake then is wonderful, but it's what happens when you're asleep, he says.

Speaker 41 That's what allows you to make very important connections in your life.

Speaker 42 And he noticed this first

Speaker 22 when he was connecting with, I believe it was a guitar.

Speaker 21 He was playing music.

Speaker 15 I used to play, for instance, I played classical guitar.

Speaker 15 I'm sure many people who play musical instruments know that you may train and train and train on a piece during the day and you get better for sure but you're never perfect

Speaker 15 and then you sleep over it the next day you wake up you play it again and now it's smooth and you know it flows beautifully

Speaker 15 That happened to you? It happened to me, it happens to lots of people.

Speaker 17 That happened to me all the time.

Speaker 7 I discovered that sometimes if I worked on a piece and put it away, went to bed and got some rust, I had it better learned than if I stayed up all night cramming.

Speaker 30 Yeah, definitely.

Speaker 36 There's one story, and I hadn't thought about this for a long time, but well, first of all, Rob and I like play in a band together.

Speaker 37 The band is called the Sisterhood of Convoluted Thinkers.

Speaker 36 And we switch instruments like a lot.

Speaker 7 She's usually the bass player.

Speaker 36 I was going to play drums.

Speaker 14 She had to learn how to play drums.

Speaker 36 So we rented a cabin.

Speaker 37 We went somewhere to rehearse. And at night, she was really just kind of practicing and practicing and trying to get this.

Speaker 36 This one particular beat, like I worked on it like a lot. I just keep going and going.

Speaker 37 I remember playing that one thing again and again and again.

Speaker 36 And I finally just gave up and went to sleep.

Speaker 36 And the next morning, I got up and went like straight to the kit and I just played it like immediately.

Speaker 7 The butt hit the stool and she was going.

Speaker 7 She could just do it.

Speaker 36 I thought it was magic.

Speaker 36 You could just learn stuff in your sleep.

Speaker 24 So in the middle of the night, somehow the things that your fingers did repeatedly and the notes that you were using to propel your fingers, all those things somehow got into, got more,

Speaker 34 got better learned.

Speaker 24 So you learned overnight or you...

Speaker 20 I mean, what does that have to do with, you remember better in the morning?

Speaker 15 What happens is that the next day you're a bit better off. What happens during the night to make you better off? This is up for contention.

Speaker 21 Tononi's contention is that sleep helps you remember by forgetting.

Speaker 7 I don't know what that means.

Speaker 21 Let me explain to you what he's saying.

Speaker 53 He says there's a limited amount of space in your brain.

Speaker 15 The real estate in the brain is pretty limited amount.

Speaker 7 That makes sense. It's a small little guy up there.
Yep.

Speaker 21 And yet every experience you have during the day is going to take away some space.

Speaker 29 It uses up a little of what you got.

Speaker 15 When you are awake, inevitably, you learn whether you want it or not. You are going around talking to me,

Speaker 15 having breakfast,

Speaker 21 going to work, then yakking on the phone with your friends, talking to your mom,

Speaker 60 very different from some of the friends, then going home, taking a bath.

Speaker 29 I take a bath.

Speaker 7 Yeah, I get it, I get it.

Speaker 60 Everything you do during the day, every thought you think, no matter how small, it all causes your brain to form new connections.

Speaker 53 This conversation, as we're having it, is reshaping my brain.

Speaker 46 Yeah.

Speaker 53 Little pathways are forming that weren't there before I sat down.

Speaker 14 Exactly.

Speaker 15 Whether we recognize it or not, lots of things are going to change your brain by the end of a waking day.

Speaker 40 So if in the middle of the afternoon you sit down with your guitar and you practice the guitar intently,

Speaker 23 those two hours you're also making connections. And because you're concentrating, maybe you're making more connections than usual.

Speaker 19 These are guitar connections.

Speaker 23 And all those synaptic connections made during the day, one

Speaker 30 on the other,

Speaker 19 on the other.

Speaker 41 By the time you're ready for sleep at the end of the day,

Speaker 32 up in your head,

Speaker 14 it's a giant, unruly mess.

Speaker 15 And that is where we think sleep kicks in.

Speaker 20 Well, I'm going to guess here, but I think you think that sleep is a garbage detail.

Speaker 24 It comes in and says, okay, you're done, you're done, you're done.

Speaker 15 It's actually even simpler than that.

Speaker 58 According to Tononi, there's not really a janitor who comes in and decides, okay, you have to leave, you get to stay.

Speaker 21 Nothing like that. Instead, he says, what happens?

Speaker 15 We think that during sleep,

Speaker 41 waves of electrical activity, kind of like a late evening bath, wash over your head.

Speaker 58 They start at the back of your head and they move to the front.

Speaker 44 These waves are called slow oscillations.

Speaker 44 And over the course of the night, 1,000 times a night, those waves wash through all the experiences of your day, all the little synaptic connections that you made all day long, and every one of those connections

Speaker 44 gets just a little bit softer.

Speaker 15 They get weaker. Progressively, gracefully, they get weaker.

Speaker 44 Even, he says, the things you want to hold on to, like the guitar.

Speaker 41 Wait a second, wait a second.

Speaker 24 You were the one who said you learned how to play the instrument in the afternoon, you went to sleep, and you played the instrument better in the morning.

Speaker 24 Why would you wake up the next morning playing better?

Speaker 20 You should play more weakly, with less confidence, and less memory.

Speaker 53 Because after all, you've just given the whole place a bath.

Speaker 59 It's all relative, sir.

Speaker 35 What he means by relative is this.

Speaker 42 That mess of new connections in your head.

Speaker 51 Some of those connections are softer. Some of those connections were louder.

Speaker 58 The random things you ordered for lunch, they're softer.

Speaker 30 I'll have a turkey on ride.

Speaker 22 Okay. But the guitar, because you spend so much time thinking about guitar technique, you spend so much energy on it, that's louder.

Speaker 42 So we're just measuring connections here.

Speaker 34 Now, imagine that sleep is a big volume knob.

Speaker 38 So listen to what happens when you lower the volume on the whole day.

Speaker 18 Lower

Speaker 18 and lower

Speaker 18 and lower.

Speaker 52 You hear how the softer stuff just falls away, you can't hear it anymore? Yeah.

Speaker 42 But the guitar, while it's getting softer too, because it was so loud to begin with, now it stands out a bit more clearly, no?

Speaker 15 Yeah. The signal, the signals that have survived reasonably well, are heard better because the background has become more silent.

Speaker 20 So your ability to play the guitar better the next morning is not because you've learned skills overnight that you didn't have before, it's because all the other stuff taken up your brain has gone down in volume, and you're left with, relatively speaking, a better guitar

Speaker 24 fingering technique.

Speaker 15 You put your finger on it.

Speaker 51 So, Mr. Tononi feels that sleep is a little bit like wind and rain, like the process of erosion.

Speaker 51 At the end of the day, or rather at the beginning of the morning, the things left standing are the things you need to know.

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Speaker 7 This is Radiolab. I'm Jad.
And I'm Robert. And today's program is about sleep.

Speaker 20 As in the kind of sleep where you perchance to dream.

Speaker 7 Exactly. Did you know that story about

Speaker 7 the benzene molecule?

Speaker 8 No. Speaking of dreams.

Speaker 14 Well, here

Speaker 7 1865. German chemist is trying to figure out the shape of this molecule, benzene.

Speaker 7 He knows that has a certain amount of one kind of atom and a certain amount of another, but he can't figure out how they all link up. Right.
And he's tortured by this problem.

Speaker 7 Ghost sleep has a dream of a snake biting its tail, wakes up, bolts right up, and says, it's a ring.

Speaker 17 It's a ring.

Speaker 19 Do you believe that?

Speaker 7 I want to.

Speaker 30 Well, yeah.

Speaker 7 I mean, don't get me wrong. I hate it when people tell me the dreams.
Hate it.

Speaker 10 I want to stab my eye with a fork, frankly, when people tell me the dreams.

Speaker 17 I don't know why.

Speaker 10 I'm never going to tell you about my dreams again.

Speaker 30 Good.

Speaker 54 But you know, you're not alone because for a long time, scientists have avoided studying dreams because they think they're so random and meaningless and unstudiable.

Speaker 35 Right.

Speaker 34 But we did meet a guy.

Speaker 63 I'm Bob Stickgold, S-T-I-C-K, G-O-L-D. I'm an associate professor of psychiatry at Harvard Medical School.

Speaker 54 Who found an interesting way to ask the question, why do we dream?

Speaker 63 Simple question, very hard answer.

Speaker 23 Robert Stickold was one of the first modern scientists to take dreams seriously.

Speaker 47 And for him, it actually began kind of by accident.

Speaker 63 I had been up in Vermont with my family. We had gone and climbed Camel's Hump, one of the higher, easy-to-climb mountains in Vermont.
We'd gone at 8 in the morning. We were back at 2 in the afternoon.

Speaker 54 And for that whole day, he'd been up climbing on the rocks, gripping them with his hands really climbing later that night I lie down I close my eyes

Speaker 63 I can feel the rocks under my hands

Speaker 63 and I sort of start all up and I say whoa that's really bizarre it wasn't like I was thinking about it I was there I could feel the rock

Speaker 63 I'd been off the mountain for eight hours. Nothing like that had happened.
I lie down in bed for three minutes starting to go to sleep. And boom, it's there.
And I tried again and I fell asleep.

Speaker 63 Two hours later, I wake up, I have to go to the bathroom, I go to the bathroom, I come back, and I say, that was way cool, I have to try that again.

Speaker 63 And I cannot get it back. What happened in those two hours to those memories that they won't intrude anymore?

Speaker 63 And then I started talking to friends. And they say, oh, try canoeing.
Or someone else says,

Speaker 63 try whitewater rafting if you want to get that. And someone else says, oh, hello, take organic chemistry.

Speaker 63 And you go to bed at night, and all you see are these bloody molecules rotating in front of your eyes. Those daytime activities are affecting your dreams.

Speaker 29 And that got him thinking.

Speaker 54 What exactly is the connection between what you do during the day and what you dream at night?

Speaker 10 What are the rules of that?

Speaker 7 He figured, all right, well, this replay is kind of interesting. Maybe I'll test it.
But how?

Speaker 63 If I get some subjects together what could I have them do during the day that would reliably end up in their dreams well he can't have them all go for a hike and I'm probably not going to get permission to take them white water rafting too expensive so what could he do it sort of sat fallow for a year and I was moaning to some of my students about how I can't think of how to do this and someone says Tetris

Speaker 63 and somebody else says absolutely

Speaker 63 and I'm saying what what they say well don't you you play Tetris? And I say, yes. Well, when you start playing Tetris,

Speaker 63 it turns out when you start playing Tetris,

Speaker 63 you go to bed at night, you lie down in bed, and you see Tetris pieces falling down in front of your eyes.

Speaker 17 Sure? Oh, yeah. You knew that?

Speaker 18 Absolutely.

Speaker 63 You guys both know that?

Speaker 14 Oh, yeah.

Speaker 63 I got a cover of a science magazine for the first published paper on dreaming in 40 years because I discovered that and everybody already knew it.

Speaker 35 It was that simple. He got a bunch of people, put them in a room, had them play Tetris.

Speaker 54 Later that night, they woke up, and 60% of them were dreaming of Tetris.

Speaker 18 60%.

Speaker 7 How do you know that? I mean, just from their reporting?

Speaker 63 As they're falling asleep, we're monitoring them electrophysiologically, and as they start to drift off to sleep, please report now.

Speaker 7 This Tetris observation was a pretty good start in terms of getting at that question.

Speaker 63 Why do we dream?

Speaker 7 Why do we dream? How does it work?

Speaker 7 What if, as a next step, instead of having the people report their own dreams, waking them up and doing that whole thing, what if, instead, you could cut the person out of the equation entirely and go right to the source.

Speaker 7 To the dream directly.

Speaker 16 Matt Wilson.

Speaker 64 I'm a researcher here at MIT. And I'm a neuroscientist studying learning and memory.

Speaker 7 That's what Matt Wilson does.

Speaker 28 It takes us to the Dream Lab. So when we first come in, what we see is this bank of monitors.
13 monitors all in a row. Each monitor displaying ongoing activity in the brain with little panels.

Speaker 31 Each panel showing these.

Speaker 7 It's like the Kennedy Space Center, really. All the monitors have data just flashing all over them.

Speaker 28 Graphs and squiggly lines and numbers.

Speaker 7 It's not immediately clear where all this information is coming from.

Speaker 7 But if you peek around the back, you'll see that all the computer wires go to one box, which then connects to a cable, which then goes up to the ceiling, over to a wall, and down into the head

Speaker 7 of one

Speaker 28 tiny rat.

Speaker 61 There he is.

Speaker 7 He's just kind of hanging out in his own little basket.

Speaker 28 See him just resting.

Speaker 7 Is that the little guy himself?

Speaker 7 He looks pretty normal, except for this cable coming out of his skull.

Speaker 7 And the cable is basically a microphone or a bunch of them, which Matt uses to eavesdrop on the brain cells inside the rat's head as they chit-chat.

Speaker 7 And this is what that sounds like.

Speaker 28 You can hear this kind of snap-crackle pop sound.

Speaker 25 These are individual cells that are firing.

Speaker 29 Like

Speaker 28 right there. One of those.

Speaker 31 That kind of whooshing sound.

Speaker 28 I can tell this animal is sitting, resting quietly.

Speaker 7 Amazingly, he says this while he has his back to the animal.

Speaker 7 He is so fluent with the Morris code language of the rat's brain cells, he doesn't even have to actually look at the animal to to know what it's doing.

Speaker 7 He can just instantly decode all of that snapping.

Speaker 7 Kind of like that guy in the Matrix, the ball guy.

Speaker 65 I don't even see the code. All I see is Bond, Brunette, Redhead.

Speaker 7 Just by listening, Matt knows when the animal is sitting, he knows when it is sleeping, he knows when it's running around in a maze. He even can tell which direction it's running.

Speaker 64 It just happened that as we were studying these patterns while the animal ran around, after the experiments, the animals would, they would get tired, they would go to sleep.

Speaker 51 I would be

Speaker 16 there in the room, but I would continue to listen to the activity.

Speaker 64 Notice how it's gotten silent.

Speaker 16 Yeah.

Speaker 64 And I began to notice that when the animals were asleep, the brain cells weren't just firing randomly. In fact, when animals would go into REM sleep, so now he is

Speaker 64 going into REM right now, the pattern of activity to hear, notice that it's not these whooshes anymore, sounded very much like the pattern that the animal had just been running through.

Speaker 64 In fact, if you weren't watching the animal, you would think, oh, the animal has gotten up and is running around again, but But then you turn and you look, and you see the animal is asleep.

Speaker 7 He checked the data, and it wasn't simply that the rat was running around in its mind while its body was asleep. It seemed to be running a specific route.

Speaker 7 The same route, in fact, that it had run earlier in the day.

Speaker 60 Same sequence, same order, same everything?

Speaker 7 Yes. It was rerunning its maze, step for step.

Speaker 7 So then he asked the next question.

Speaker 64 Are they seeing the things that they saw while they were awake? We can actually look into these questions as a rat, a fact.

Speaker 17 And so

Speaker 64 the answer is we see evidence of replay in basically all of the parts of the brain that we have looked in.

Speaker 7 Do they see the maze that they ran through? The very same maze? Yes, they see.

Speaker 9 So that is dreaming in a sense.

Speaker 16 Well, they are.

Speaker 64 How do we define dreaming?

Speaker 7 Sounds like dreaming to me.

Speaker 63 I don't know.

Speaker 7 But the question remains,

Speaker 7 why would the rat or any creature do this? And so Matt came up with a simple next experiment. He decided to give the rat two mazes.

Speaker 66 What would that do to its dreams of the night, or whatever you want to call them?

Speaker 64 If they run on maze number one

Speaker 64 and then on maze number two, we see them running maze one and maze two together in a way that they did not experience when they were awake.

Speaker 7 Oh, so it's like a remix of

Speaker 7 a new pattern that includes part of maze one and part of maze two. It turns out that when the rat had more than one maze in its memory, it began to invent completely new mazes.

Speaker 64 This gives us the thought that sleep is this unique opportunity to basically run through events, to put them together in ways that may not have occurred while the animals were awake.

Speaker 64 And that's what learning really is.

Speaker 64 Learning is about synthesis, about taking things that were inherently unrelated and figuring out the connection, that is, figuring out the rules, the hidden rules, the undiscovered rules that will allow us to create something new.

Speaker 63 I think dreaming is a time when we try out possibilities that in waking we might not feel were worth trying. And when it really works,

Speaker 29 it can be profoundly important.

Speaker 21 If Robert Stitgold is right, then how does this

Speaker 19 solving the problem thing, how does it work?

Speaker 52 How does the brain decide what to put into a dream and what to leave out of a dream?

Speaker 63 One of the interesting things about dreams is that people don't have dreams where they're word processing, where they're surfing the net.

Speaker 63 These things that they spend huge amounts of their day doing don't get into their dreams.

Speaker 7 But somehow Tetris gets in there every time.

Speaker 17 Every time.

Speaker 7 Why would that be? Well, he has a hunch. Which he's actually exploring with a completely different video game.

Speaker 63 We've moved to a game called Alpine Racer, which we bought out of an arcade.

Speaker 7 Which he showed us. This way.

Speaker 7 Took us down the hall to the game room.

Speaker 54 Here we are. And there, in the corner, it stood.

Speaker 18 Mockingly.

Speaker 10 Oh, wow, it's a full body game.

Speaker 54 Please step up. I stepped up to the

Speaker 63 right, it's trying to lock itself out. Got on the platform.
It's still warming up.

Speaker 21 And then I set off

Speaker 41 down a virtual mountain.

Speaker 66 Alright, I'm going down the hill. I'm also a girl.
I'm also avoiding the ski. Oh, what? Do I get a nice little turn there? Be careful of the little wall.
Straight down ahead.

Speaker 38 And down we go.

Speaker 48 Oh, no, no, that tree. Wait,

Speaker 18 wait!

Speaker 21 We're now going to go through the tunnel. This is a...

Speaker 18 Ow!

Speaker 18 Oh, that hurts!

Speaker 26 As you can hear, this game was really stressful, which is by design.

Speaker 20 Robert Stickle has the theory that as you go through through your day, your brain is constantly keeping track of emotions.

Speaker 46 That's the thing, emotional content.

Speaker 60 Like when you run into a virtual tree, for example. Your brain is gonna flag that stuff.

Speaker 63 It's gonna flag that is important.

Speaker 66 It says, ooh, I need to remember this so I can work on it later.

Speaker 21 I'm gonna put a sticky on this one.

Speaker 63 So if it puts a sticky on everything that's hard during the day, then all the brain has to do when it's creating a dream is go and grab stickies.

Speaker 54 Oh, and then I died, but I died nice.

Speaker 63 Just for the record, you got further than Jad on your first try.

Speaker 17 Wow.

Speaker 17 Wow.

Speaker 14 It's like,

Speaker 18 and it's over.

Speaker 17 Could you say that again?

Speaker 7 Have people play Alpine Racer for 45-minute bursts throughout the day. What happens next? You wake them up?

Speaker 63 We monitor their brain activity, and just as they're falling asleep, within the first two minutes after they fall asleep, we'll wake them up.

Speaker 18 Please report now.

Speaker 63 There's a microphone right next to them in their bed, and they just report what was going through their minds.

Speaker 61 I was just thinking about skiing.

Speaker 57 Skiing.

Speaker 63 Skiing. And we get on the first night up to 40% of all the reports being about skiing.

Speaker 61 And the game that I've been playing. Oh, quite ski racer, okay.

Speaker 63 40%.

Speaker 63 Almost half of them.

Speaker 63 And that's right up there what I would expect to see after trauma, where something has been labeled so intensely that the brain says, okay, it's obvious what's on the agenda for tonight.

Speaker 7 Stickold thinks he's seeing the outline of the dream-making process here. It starts really simply at the very beginning of sleep, like right after you fall asleep with the replay.

Speaker 7 This, he suspects, is just the brain emptying out its stickies.

Speaker 23 Things that really intrigued me during the day, that I felt during the day.

Speaker 63 Yeah, but what happens if we let the people go to sleep, sleep two hours like I did in that very first time after climbing the mountain, wake them up after two hours of sleep?

Speaker 21 Because remember, he couldn't get back the memory of the rocks after he'd spent two hours of sleep.

Speaker 7 That's right, and what he's found is that if you fast forward two hours into the dream, you get almost no reports of skiing at all. The replay seems to dissolve into a remix.

Speaker 63 We start getting reports like,

Speaker 63 oh, I dreamt I was sliding down a hill.

Speaker 57 Like I'm

Speaker 6 going downhill.

Speaker 63 Just rolling down a hill.

Speaker 57 Downward motion.

Speaker 61 I was thinking about a...

Speaker 61 I was about to say a downhill banana.

Speaker 61 I was thinking about skateboarding. I was thinking about

Speaker 61 a bunch of bananas. Doing yoga on a ski slope.

Speaker 63 Someone else had a dream that they were rushing through a forest with their body incredibly stiff and their legs not moving at all as if they were on a conveyor belt.

Speaker 7 It's like as the dream goes on, the brain is starting to free associate.

Speaker 7 What do I have in my past that has anything to do with mountains, anything to do with crashing or skiing, anything at all that can help me?

Speaker 63 What do I have in all my memories, in my case from the last 60 years, that fits associatively, thematically? And the result?

Speaker 7 Well, it might seem random, it is. But every so often, he says, you come up with the right answer.

Speaker 63 So now we get to your dreams of people discovering the structure of benzene. Kukul was his name.

Speaker 7 Kekul, excellent, was his name.

Speaker 32 Auguste Kekul.

Speaker 7 He was the German guy I talked about earlier who had a dream of a snake eating its tail and realized from that dream that the shape of the benzene molecule is a ring.

Speaker 7 I don't know if that dream is true, but maybe that is in fact the point of dreaming.

Speaker 7 It's this time when you shut off the outside, turn inside, take the problems that you've got, and start to really work on them, pull them apart, make connections that you wouldn't normally make during the day.

Speaker 21 However, have you ever wondered why it would be necessary when solving problems like this to dream so vividly?

Speaker 53 Are you at all puzzled by the super-duper technicolor, extraordinarily cinematic quality of some of these things?

Speaker 20 Because if it were just an everyday brain function to sort of make sense of the world and allow you to make new connections, you really wouldn't need quite the

Speaker 19 movie quality.

Speaker 63 So when we talk about dreams, what seems to come into dreams are memories, concepts, relationships, associations that have a strong emotional flavor.

Speaker 63 And I'm guessing from the data, need a full-blown orchestration to be properly processed. And it is, it's technicolor.
The colors are overwhelming almost.

Speaker 7 So, if I hear you right, what you're saying to Robert's question about why are the dreams so

Speaker 7 vivid is that I don't know, but maybe the vividness helps.

Speaker 63 That whole long answer is what a Harvard professor says instead of saying, I don't know.

Speaker 1 All right, that's all we got for today. If you'd like to learn anything more about what you heard in today's show, please visit radiolab.org.

Speaker 67 Hi, I'm Sameen, and I'm from Oakland, California. And here are the staff credits.
Radiolab was created by Jad Abumrad and is edited by Soren Wheeler. Lulu Miller and Latif Nasser are our co-hosts.

Speaker 67 Dylan Keefe is our Director of Sound Design. Our staff includes Simon Adler, Jeremy Bloom, Becca Bressler, W.

Speaker 67 Harry Fortuna, David Gable, Maria Paz Gutierrez, Cindy Yanam Sambundam, Matt Kielty, Annie McEwen, Alex Neeson, Valentina Powers, Sarah Carey, Sarah Sandback, Arianne Wack, Pat Walters, and Molly Webster.

Speaker 67 Our fact-checkers are Diane Kelly, Emily Krieger, and Natalie Middleton.

Speaker 68 Hi, I'm Erica Inyonkers.

Speaker 68 Leadership Support for Radio Lab Science Programming is provided by the Gordon and Betty Moore Foundation, Science Sandbox, a Simons Foundation Initiative, and the John Templeton Foundation.

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