0:00

Uber One will save you. Uber One

0:04

will save you. La la

0:07

la la la la la. Uber

0:09

One will save you. Uber One will

0:12

save you. On all

0:14

your Eats, savings can't

0:17

be beat. Up to 10% off

0:19

your orders.

0:21

Join Uber One. Members save up

0:23

to 10% on Uber Eats. Get that

0:25

stuck in your head. $0 delivery fee and percentage off

0:27

discount subject to order minimums and participating stores. Taxes and

0:29

other fees still apply.

0:31

Sergeant and Mr. Smith,

0:33

you're going to love this house. Bunk

0:36

beds in a closet? There's

0:38

no field manual for finding the right home. But

0:40

when you do, USAA Homeowners Insurance

0:42

can help protect it the right way. Restrictions

0:45

apply.

0:47

This program is sponsored by the Kavli

0:49

Foundation based in Los Angeles,

0:51

California. The Kavli

0:53

Foundation is dedicated to advancing

0:55

science for the benefit of humanity.

1:03

I'm Alan Alda, and this is Clear

1:06

and Vivid, conversations about

1:08

connecting and communicating. You

1:11

know,

1:13

I often think of DreamSleep as a Google

1:15

search gone wrong. Let's say that, you

1:17

know, I type into Google, Alan

1:20

Alda, and the first page is all of

1:22

your incredible back catalog of accomplishments.

1:25

But then I go to page 20, and

1:27

it's about a field hockey game in Utah.

1:30

And I think, hang on a second, what on earth

1:32

is... But if I read it and I look, there's

1:35

a very distant, very non-obvious

1:37

association. When you start to

1:39

collide things together that shouldn't normally

1:42

go together, it sounds like the

1:44

biological basis of creativity. And

1:47

no wonder as a consequence, no

1:49

one has ever told you, you know, Alan, you should really

1:52

stay awake on a problem.

1:53

That's Matthew Walker. He's

1:56

the ultimate sleep guru. He's

1:58

the author of a best-selling book called, why we

2:00

sleep and he's the host of the

2:02

Mac Walker podcast where he addresses

2:05

just about every question about sleep you've

2:07

ever asked which is

2:09

why I began our conversation with an

2:11

urgent question of my own. This

2:14

is really important that you're here today

2:17

because I'm groggy today and

2:19

I need I need a diagnosis. Here's

2:21

what happens in the middle of the night I

2:23

woke up because of the call of nature. When

2:26

I was back in bed I thought

2:28

okay this should just take a couple of minutes half

2:31

an hour later 40 minutes later I'm still

2:33

staring into the dark. So I took

2:35

a half an Ambien. You did. And

2:38

it did put me to sleep. Now is

2:40

there anything wrong with taking that kind of a pill?

2:43

I'm typically not the biggest fan of

2:46

Ambiena and it's like kind brethren

2:49

because the way it works is by

2:52

simply sedating your brain. It goes after

2:54

the inhibitory neurons of the cortex

2:57

and knocks them out. So when

2:59

you take Ambien you certainly lose consciousness

3:03

but to argue you're in naturalistic sleep

3:05

is an equal fallacy I think because

3:08

if I show you the electrical signature

3:10

of your sleep with Ambien versus

3:12

naturally it's a very different signature.

3:15

There's a particular dent in your deep

3:17

sleep that is perhaps undesirable.

3:20

There are some medications that I would suggest

3:22

though. One of them is

3:24

a new class of drugs called the DORAS.

3:28

D-O-R-A small

3:31

s and it stands for dual Erexin

3:34

receptor antagonist. It's a fancy way of saying

3:37

we discovered that there is a chemical in

3:39

the brain that in narcoleptic patients

3:41

is deficient and it's called Erexin and

3:44

it's the weak promoting chemical. So

3:47

because patients with narcolepsy are

3:49

constantly falling asleep inappropriately

3:52

during the day we realized it's because

3:54

they don't have enough of this erection

3:57

chemical like a finger to flip

3:59

the light.

3:59

on the wakefulness switch of the brain.

4:03

So after that discovery, some

4:05

smart people and drug companies realized, well,

4:08

insomnia is the reverse problem, where

4:11

at night, people need

4:13

to get sleepy, but they can't.

4:16

Whereas in patients with narcolepsy,

4:18

they want to stop being sleepy during

4:21

the day. So they reverse the chemical

4:23

equation. And they develop drugs that rather

4:26

than enhanced orexin,

4:28

which is what we have for strokes for narcoleptic

4:30

patients, which brings them awake during the day,

4:32

we block it with these new

4:34

form of drugs, and we turn off

4:36

the light switch chemical of wakefulness.

4:40

And therefore we let naturalistic sleep

4:42

come to your brain rather than just simply

4:44

sedating it. Right. I'm

4:47

curious about other things that may interrupt or

4:50

prohibit the natural evolution of

4:52

the sleep process. Like what about

4:54

taking naps? It's a great

4:57

question. And naps

5:00

are a double edged sword. We find

5:03

that naps where you go up to about 15

5:05

minutes and beyond, they give some amazing

5:08

benefits for both brain and for body.

5:10

You have to be a little bit careful with making the nap too

5:13

long. Once it goes past 20 minutes, you

5:15

go into the deeper stages of sleep. And

5:17

when you come out of that longer nap,

5:19

it's as though someone woke you up at,

5:22

you know, 2am. Boy, do

5:24

you not feel awake. If

5:26

you come out of deep sleep, we all have

5:28

that type of experience. But

5:30

the more dangerous concern I have

5:33

is not about the sleepiness

5:35

you feel after you've napped when you wake

5:38

up during the day. But more importantly, how

5:40

does that nap impact your

5:42

sleep at night? And my advice

5:44

to people is if you are struggling

5:47

with sleep at night, do not nap

5:49

during the day. Because

5:51

as you're awake during the day, you're

5:54

building up this incredible, wonderful

5:56

sleepiness chemical called adenosine.

5:59

And the more of it you build up the sleepier

6:01

that you feel. And after about 16 hours

6:03

of sleepiness, chemical, and then the same

6:06

building up, you should be able to fall asleep

6:08

and stay asleep. But if you bring that back

6:10

to naps, if you nap during

6:12

the day, it's like a pressure valve

6:15

on a cooker. And you just release

6:17

some of that healthy sleepiness. And

6:19

then when it comes time for you to fall asleep

6:21

at night, it's going to be harder for you

6:23

to fall asleep or harder for you

6:26

to fall back asleep when you wake

6:28

up. Because you haven't got as much weight

6:31

of healthy sleepiness weighing you down because

6:33

the nap evacuated some

6:35

of that healthy sleepiness. Does that make some sense,

6:37

Alan? It does. Somebody

6:40

mentioned to me that Thomas Edison, who

6:42

was famous for taking naps, had

6:45

a way of waking himself up without an alarm

6:47

clock, I think. Brilliant. Edison

6:50

was an acclaimed short sleeper. And people

6:52

say to me, well, if sleep is so great for creativity

6:54

and problem solving, Edison

6:57

said he didn't sleep very much at night.

7:00

How do you square that circle? And

7:02

he was a habitual nap during the

7:04

day. I've got lots of great pictures of him

7:06

on his work venture in the garden taking a

7:08

nap.

7:08

And

7:10

he understood the power

7:12

and brilliance of napping for creativity.

7:14

And he used it ruthlessly as a tool. And

7:17

you're right. What he would do is he would sit in a study

7:19

with an armchair that had a rest

7:21

on it for his arms. He would take two

7:23

steel ball bearings and pick them up in his hand. Then

7:26

he would place a metal saucepan underneath

7:29

the arm of the chair. And

7:31

then he would put a pen of paper and a pencil

7:33

on his desk. And he would gradually

7:36

lean back. And so he didn't

7:38

go too far into that deep sleep, as

7:40

you described. What happens as we go deep

7:42

into sleep on muscle tone relaxes,

7:45

he would release the steel ball bearings. They

7:47

would crash on the saucepan, wake

7:50

him up, and then he would write down all of the

7:52

ideas. And in fact, he

7:54

had a phrase for it. He called it the genius

7:57

gap. And he would in. If

8:00

you look at photos historically of his house, he

8:02

had around his house what he called nap

8:05

cots, like little cots for children

8:08

but for humans. And they were designed so

8:10

you could go there and take a nap. Isn't that

8:13

genius? Isn't

8:15

that brilliant? Maybe

8:19

it's time to ask you what is sleep?

8:22

What happens in sleep? What's

8:25

it for? How does it work? Well,

8:27

sleep is a process at least in humans

8:30

and in fact in all mammalian species. It's

8:33

broadly separated into two main

8:35

types. I think many of us sense that

8:38

at night I go to bed and my

8:40

mind is largely blank and my body is still

8:43

and I just have this thing called sleep and then eight

8:45

hours later I wake up. But sleep

8:47

is much more complex and

8:50

firstly we have two main types called non-rapid

8:53

eye movement sleep and rapid

8:55

eye movement sleep or non-REM and REM

8:57

sleep. And non-REM

9:00

sleep is further divided into

9:02

four separate stages. Unimaginatively

9:07

called stages one through four were

9:09

incredibly creative in the sleep field. Need

9:12

to get it rest. Yeah,

9:15

I know. Come on. Let's get Edison

9:17

involved. Stages

9:19

one and two are really what we think

9:22

of as light non-REM sleep. Stages

9:24

three and four are what we think of as deep non-REM

9:26

sleep. And REM sleep

9:28

is really the stage that's most associated

9:31

with dreaming depending on your definition. And

9:34

those two types of sleep will

9:37

play out in this incredible battle

9:39

for brain domination throughout

9:41

the night. And that's sort of... REM

9:44

and non-REM sleep will battle? Yeah.

9:46

So essentially biologically battle and

9:49

that cerebral war as it were

9:52

in that battle is going

9:54

to be won and lost every 90 minutes

9:57

and then replayed every 90 minutes.

9:59

such that when we fall

10:02

asleep and when you and I fell asleep last night, we

10:04

went down into light non-REM sleep, then

10:07

deep non-REM sleep, and after about 40 or 50

10:09

minutes, we started to rise back up,

10:12

and then we popped up and had a short REM sleep period,

10:14

and then back down we go again, down into non-REM

10:17

and up into REM. And

10:19

on average, that cycle is 90 minutes, but

10:21

it varies across people. What's

10:24

fascinating, however, and this is

10:26

really interesting because sleep science

10:29

has yet to truly come up with an

10:31

explanation as to why, but

10:34

in the first half of the night, the

10:36

majority of those 90-minute cycles

10:38

are comprised of lots of deep non-REM

10:41

sleep and very little REM sleep.

10:44

But as you push through to the second half

10:46

of the night, that seesaw balance

10:48

actually changes, and we have

10:50

much more REM sleep, dream sleep,

10:52

and very little deep sleep. So

10:55

we don't know why. What are we doing

10:58

up there in our brains while

11:01

we're going through those different stages? Well,

11:04

as ever, I mean, it's an insightful question because

11:06

that gets at causality, and we've done these

11:08

studies where we can selectively excise,

11:11

like a surgeon, your deep

11:13

sleep at night, and so

11:15

you still sleep a full eight hours through

11:18

some very clever mechanisms. We

11:20

can selectively wipe out the deep sleep,

11:23

or we can selectively wipe out the

11:25

REM sleep, and you're still asleep, but

11:27

for the most part, we take each one of those out,

11:29

and then we measure the consequences. The

11:31

first is that deep sleep is critical

11:34

for hitting the save button on our new

11:36

memories.

11:37

Deep sleep protects our memories,

11:40

and it saves them and cements them, and

11:42

solidifies them into the neural architecture of the

11:44

brain, so you let you don't forget. We

11:47

also know that deep sleep is

11:50

critical for refreshing the short-term

11:52

memory system of the brain, so that

11:55

when you wake up the next day, you have

11:57

a cleared-out sort of cache memory

11:59

almost like a...

11:59

computer or better

12:02

still the analogy would be like a USB stick

12:04

you've moved the files you know onto

12:06

the hard drive and the next day you wake up with

12:08

your USB stick you can start gathering

12:11

new files all over again that's a

12:13

second memory benefit. The

12:16

third benefit that we've discovered starts

12:18

to move downstairs into the body that

12:20

deep sleep is immensely useful

12:23

firstly for restocking

12:26

the weaponry in your immune

12:29

arsenal so that you wake up

12:31

the next day a much more immune robust

12:33

individual. The second

12:36

is the cardiovascular system. Deep

12:39

sleep acts it's

12:41

almost as though it's the very best form

12:43

of blood pressure medication that you could ever

12:46

wish for. The vessels relax

12:49

the heart rate drops the nervous

12:51

system shifts over from that fight-or-flight

12:54

branch which we don't really like

12:56

to see for your cardiovascular system cortisol

12:59

levels drop down and you just

13:01

go into this very quiescent

13:03

cardiovascular state that is

13:06

wonderful as a restitutive device

13:09

for your cardiovascular health.

13:12

Probably the third thing and maybe this

13:15

almost trumps those others in

13:18

terms of the size of the effect is

13:20

how your body regulates your

13:23

blood sugar and it's called your metabolic

13:25

health and deep

13:27

sleep is critical for resetting

13:31

your ability to regulate

13:33

insulin and therefore regulate

13:35

glucose. So the next day when

13:38

you eat food what we like to see in

13:40

the field of medicine is that when you have

13:42

let's say a big meal a bowl

13:45

of sort of porridge in the morning

13:47

you know to hearty to get you started what

13:49

we don't want to see is a big

13:52

sugar blood sugar spike because

13:55

that actually is toxic to your

13:57

cells of your body and your brain and that's why fear

14:00

it for conditions like tectoid diabetes.

14:03

But deep sleep helps you better

14:06

control your blood sugar response

14:09

and it helps the body and the cells

14:11

of the body firstly receive

14:13

more insulin signaling to say hey

14:16

there's more blood sugar around it's time for

14:18

you to take out the

14:20

spike in glucose in your blood and

14:23

it helps the cells essentially stick

14:25

out their straws into the bloodstream and

14:28

start sucking up

14:29

the blood sugar so you don't

14:32

get that dangerous spike. So

14:34

these are all of the ways that deep sleep

14:37

at least helps your brain and your body but then we've got REM

14:39

sleep of course. Here's what I don't get. REM

14:41

sleep better have something great to offer

14:44

or why is it fighting for dominance

14:47

against these important biological

14:50

benefits you get from deep sleep?

14:52

It's very interesting isn't it? One of the founding fathers

14:55

of sleep research William Dement at Stanford

14:57

back in the 60s deprived participants

14:59

of REM sleep every night for about

15:02

six nights and very

15:04

quickly the thing that fell apart

15:06

was not their cognitive acumen

15:09

and health necessarily it

15:11

was their emotional health and

15:14

wellness. They started to become incredibly

15:17

emotionally erratic. They started

15:19

to become very pendulum

15:21

like in their emotional activity. They would giggle

15:24

and laugh very quickly and then they would be crying

15:26

five minutes later in deep

15:29

sadness. They started to then hallucinate.

15:31

They saw things that were not there. In

15:34

other words they were starting to become psychotic and

15:36

that happened by about day four and

15:38

we've now done gosh a vast amount

15:40

of work in this area of sleep and mental

15:43

health and REM sleep is

15:45

proving to be REM sleep

15:48

when you get it is a form of emotional

15:50

first aid. It provides overnight

15:53

therapy and it takes these

15:55

difficult painful experiences that we've been

15:57

having and almost like a nocturnal

15:59

soothing balm, it takes the sharp

16:02

edges of them so that we come

16:04

back the next day and we feel better

16:06

about those things.

16:08

And so it's not time that

16:10

heals all wounds, but time during dream

16:12

sleep that provides that emotional convalescence.

16:15

That's one of the benefits of REM.

16:18

REM sleep is also, by the way, critical for creativity

16:22

and deep sleep saves

16:24

those individual memories but REM sleep

16:26

then comes along and takes those individual

16:29

new memories and starts colliding

16:32

them with all of the back catalog

16:34

of information that you've got stored in your brain.

16:37

You know, I often think of dream sleep as a Google search

16:39

gone wrong. Let's say that, you

16:41

know, I type into Google, Alan

16:44

Alder, and the first page is all of

16:46

your incredible back catalog of accomplishments.

16:49

But then I go to page 20 and it's about a field

16:51

hockey game in Utah. And

16:54

I think, hang on a second, what on earth?

16:57

But if I read it and I look, there's a very

16:59

distant, very non-obvious association.

17:02

That's what dream sleep seems to be about.

17:05

It's not about seeing the logical, obvious

17:07

things, which is what our brain does during the day. It's

17:10

about seeing the non-obvious, distant

17:13

connections. Because when you start to

17:15

collide things together that shouldn't normally

17:18

go together, but when they do cause

17:20

marked advances in evolutionary

17:22

fitness, it sounds like the biological

17:25

basis of creativity. And

17:27

no wonder as a consequence, no

17:29

one has ever told you, you know, Alan, you should really

17:32

stay awake on a problem. People

17:35

say, you should sleep

17:37

on it. And that's one of the functions of REM. But

17:39

downstairs in the body, REM sleep is

17:41

also critical for hormonal health. And

17:43

this comes on to why it may be so fundamentally

17:46

essential for life maintenance.

17:50

REM sleep is the time when we have our peak

17:52

release of testosterone. And by the way, testosterone

17:55

is essential for both men and

17:57

women, not just. a

18:00

male hormone. We also know that REM

18:02

sleep is critical for regulating

18:05

and maintaining your ability

18:08

to control body temperature. That's

18:10

another reason why REM sleep is so fundamental.

18:13

People should not underestimate. We

18:15

live as human beings in a very

18:18

narrow window, in a dangerous precipice

18:21

of thermal neutrality. And

18:23

if we fall off the edge of that curve, and

18:25

it's a very small distance, that's why your

18:28

doctor, if you go into a fever, boy,

18:30

they will say, get to the hospital if

18:32

it's starting to really get dangerous. It's

18:34

incredibly good.

18:35

And REM sleep regulates that.

18:49

The interesting thing about REM sleep to

18:51

me is that mostly,

18:54

we're immobilized, we're frozen.

18:58

And REM sleep disorder is

19:00

where the whole

19:03

body starts to respond to

19:05

the dream as if it's real, which

19:08

is what I experienced, and it was what made

19:11

me suspect I had Parkinson's. And

19:14

it doesn't seem to be widely known. No,

19:16

it's not. I had to really request

19:19

further investigations before

19:21

it was determined that I really did have Parkinson's.

19:24

So firstly, as you were describing,

19:27

when all of us typically go into REM

19:29

sleep, our brain not

19:32

only becomes very active in some

19:34

parts of your brain during REM sleep are up

19:36

to 30% more active than when you're awake.

19:40

Downstairs in the body, it sends a signal

19:42

all the way down your spinal cord to

19:44

what's called the alpha motor neurons.

19:47

And essentially, it paralyzes all of

19:49

your voluntary skeletal muscles. So you can't

19:51

speak, you can't talk, you can't do anything. That's

19:54

the normal state. So we are locked in this physical

19:57

incarceration, this penitentiary of

19:59

paralysis. this when we go into dream

20:01

sleep. Why? Because your brain

20:04

paralyzes your body so your mind can

20:06

dream safely so you don't act out your dreams.

20:09

But then what we started to discover and

20:11

gosh we started to do some of this

20:13

work back when I was just getting into sleep research

20:16

20 years ago, we started to see signs

20:19

that Parkinson's patients

20:22

maybe even 10 up to 15 years

20:25

before were already experiencing

20:28

an absence of this REM

20:30

sleep paralysis such that they started to act

20:32

out some of their dreams. And

20:35

it almost became a prognostic

20:38

canary in the coal mine that it

20:40

seemed to be predictive of what may

20:43

be coming up in 10 to 15 years. Now, as

20:46

well you understand, it's

20:48

not 100% diagnostic just

20:51

because you develop REM sleep behavioral

20:53

disorder. It typically begins in sort

20:56

of 50s early 60s doesn't

20:59

mean that it's a predetermined then destiny,

21:01

but it does increase the

21:04

probability and risk markedly.

21:07

And if that happens, I would say people

21:09

should go to the doctor if the doctor

21:11

is not aware of it, which they probably won't be because

21:14

we've done surveys and we found that across

21:16

about 10 different countries doctors on average

21:18

only get about one and a quarter house

21:21

of sleep education. It's not their fault. They don't

21:23

know. And you

21:25

should alert them to this fact and then see if

21:27

you can find a neurologist and particularly a board

21:29

certified neurologist who also has

21:31

sleep training and they will definitely understand.

21:40

When we come back from our break, Matt Walker

21:42

tells me about the connection between sleep

21:45

and Alzheimer's disease and

21:47

why that link might offer new hope in

21:49

preventing its onset. benefit

22:00

of humanity. The Foundation's

22:02

mission is to stimulate scientific

22:05

research in astrophysics, theoretical

22:07

physics, nanoscience, and neuroscience,

22:11

to strengthen the relationship between science

22:13

and society, and

22:15

to honor scientific discoveries with

22:18

the Copley Prize.

22:21

Etsy has it, everyone. Yes, it's

22:23

true. Etsy is where style

22:25

seekers, vintage hunters, long-time renters,

22:28

and new homeowners alike go to shop for style,

22:31

home decor, and gifts from independent

22:33

sellers. Are you looking for signature

22:35

jackets, hand-woven linens, and personalized

22:37

jewelry for your wardrobe? Etsy has

22:39

it. Or maybe some stunning artwork, pillows,

22:42

and rucks for your home? Etsy has it.

22:44

How about gifts for any occasion, like

22:46

handmade throw blankets, mugs, totes, and

22:49

rings? Yep, Etsy has it.

22:51

There's so much to discover, and we can't

22:53

wait for you to find what your style-seeking,

22:55

home-upgrading, gift-giving heart desires,

22:58

whatever it is you're looking for, whether

23:00

it's serveware and table linens for entertaining,

23:03

or a handbag and a perfect jacket to make

23:05

sure you're looking like your best self at any given

23:07

moment. This is your invitation to

23:09

find it because Etsy has it.

23:12

Find home, style, and gifts for you for

23:14

all budgets and any occasion. Etsy

23:17

has it. Shop at Etsy.com.

23:20

Your next guest will be left in the

23:22

door, joint number one. Please save way

23:24

more if you've never shifted. You better

23:26

get your civil life and keep doing so much

23:29

more. Join Uber One and save. Your

23:31

door will deliver you for the new off-diploid, and get your order

23:33

minimums in for the next year. This is a useful

23:38

night. This is clear and vivid,

23:40

and now back to my conversation with Matt

23:42

Walker. For some 20 years

23:44

now, he's been studying a possible role

23:47

for sleep in Alzheimer's disease.

23:51

more

24:00

significant lifestyle factors that

24:02

can determine your

24:05

risk for developing Alzheimer's disease. And

24:07

I don't make that statement flippantly, but the

24:10

first evidence that we found was looking

24:12

at associational studies. We saw

24:15

that people who were reporting sleeping six

24:17

hours or less throughout their life had

24:19

a markedly increased risk of developing

24:21

a lot of Alzheimer's disease, toxic

24:24

proteins in their brain. And two

24:26

of the toxic proteins linked to Alzheimer's

24:29

are called amyloid protein or beta

24:31

amyloid. And also another protein

24:33

called TEL. They seem to be two culprits

24:35

in the Alzheimer's equation. And

24:38

the less sleep that people are getting across the lifespan,

24:40

the more of those two Alzheimer's

24:43

had toxic proteins that they had. And

24:46

then we looked at patients who had lifetime

24:49

insomnia. And they also had a much higher

24:51

risk of developing Alzheimer's. No

24:53

two did patients with untreated sleep,

24:55

insomnia or snoring. Now

24:57

that's epidemiological correlation. Correlation

25:01

is not causation. So we went in

25:03

search of causality. And

25:05

what we've discovered in both animal

25:08

models, this is other people's work and others

25:10

in humans like myself, that

25:13

if you deprive human beings

25:16

of sleep or even you selectively

25:18

deprive them now of just deep

25:20

sleep, the next day we can measure

25:23

an increase significant, a meaningful

25:25

increase in these Alzheimer's

25:27

proteins, beta amyloids in TEL

25:30

circulating in the bloodstream, circulating

25:33

in the cerebrospinal fluid that bathes

25:36

the brain. And with special brain scanning

25:38

technology, we can see those building up in

25:40

the brain itself. Now, please,

25:43

people listening,

25:43

don't start thinking, oh my goodness,

25:46

I had a bad night of sleep last night. I'm going

25:48

to develop Alzheimer's disease by the weekend.

25:51

No, that's not that's I'm not

25:53

scaremongering. And this is to

25:55

be taken, you know, with some degree of rationality.

25:59

it taught us causality that

26:03

rather than two things going hand in hand, if

26:05

I selectively dial down one of those things,

26:07

either total sleep deprivation or selective deep

26:09

sleep deprivation, I can causally increase

26:12

the accumulation of Alzheimer's proteins.

26:17

Then the question became for us

26:19

as a field, well, if that's

26:21

true, if when you lose sleep,

26:24

you instigate Alzheimer's pathology,

26:27

what is it about sleep when you do

26:29

get it that deescalates

26:31

and reduces or prevents the build

26:34

up of Alzheimer's pathology? And

26:36

this came on to a stunning

26:39

discovery by a scientist called Megan

26:41

Nedegard at the University of Rochester.

26:44

And she was working in mice and

26:47

for a long time before her work, we

26:50

didn't think that the brain had its own cleansing

26:52

system. Now we knew the body had one and everyone's

26:55

familiar with your body's cleansing system.

26:57

It's called the lymphatic system. But

27:00

she discovered, in fact, that the brain has

27:02

a waste system and it's called the

27:04

glymphatic system named after the cells

27:07

that create it called these glial

27:09

cells. And what she

27:11

found firstly was that yes, the

27:13

brain seems to have this device, this

27:16

cleansing system, this amazing

27:18

waste expelling

27:21

system. Then if that wasn't

27:23

stunning enough, she made two more

27:25

discoveries. First, what she found

27:27

was that that that cleansing

27:30

mechanism is not always switched

27:32

on in high flow volume across

27:35

the 24 hour period. It's only

27:37

when those mice was going to sleep

27:40

that the sewage system kicked into high gear

27:42

and cleanse the brain of all the metabolic

27:45

detritus that was building up. And

27:47

then the third discovery that she made,

27:50

which comes back to our Alzheimer's

27:51

discussion, is

27:53

that two of the toxic

27:56

sticky proteins that the lymphatic

27:59

waste system...

27:59

of the brain was clearing during

28:02

deep non-REM sleep at night was

28:05

this thing called beta-amyloid and

28:07

tau protein, the two culprits of Alzheimer's.

28:10

So now we understood, okay, why

28:13

is it that when you lose sleep, especially deep

28:15

sleep, you increase

28:17

your risk and you develop more

28:20

of these proteins? We had a mechanism.

28:24

And then other people, and we've

28:26

done some of these studies too, have now seen

28:28

a very similar pulsing cleansing mechanism

28:31

in the human brain itself during deep

28:33

sleep. And that leads me

28:35

on to perhaps the fourth area

28:38

of our work, which is the

28:40

most dangerous word of all, and

28:42

it's the word of hope. And I am

28:45

very reticent almost to discuss

28:47

it, but Alzheimer's

28:49

disease as a condition right now, we are

28:51

very reactive. And

28:54

so we do late stage attempted

28:57

treatment rather than midlife prevention.

29:01

But now knowing what I know about deep

29:03

sleep, and by the way, our decline

29:05

in deep sleep, which is a natural part

29:08

of aging, unfortunately, it doesn't

29:10

start to happen in our 70s. We

29:12

can see the decline in deep sleep starting

29:15

to happen even in your late 30s. What

29:18

if I could augment human deep

29:20

sleep in midlife and

29:23

prevent the decline in the great depression

29:25

of deep sleep across the second

29:27

half of life? Could I bend

29:30

the arrow of Alzheimer's disease risk

29:33

back on itself and sort of

29:35

reduce down and de-risk that

29:38

situation by intervening?

29:40

So I shift from a model of late stage treatment

29:43

to a model of midlife prevention.

29:46

And how we're starting to try to think about

29:48

that in our latest work.

29:58

speaking

30:00

with you. I want

30:02

to hear more and I'm sure our listeners want to hear more.

30:05

I would suggest they go to your book and

30:08

your podcast and pick up the conversation

30:10

there. We're running out of time here,

30:13

but we always end our show with seven

30:15

quick questions where we learn just

30:17

a little bit more about you. Of all the

30:19

things, number one, of all the things there are

30:21

to understand, what do you

30:24

wish you really understood?

30:26

Gosh. With sleep,

30:29

I think what I would love to try to understand

30:31

is how I could

30:33

compress sleep almost like a zip file.

30:35

You know, you take all of those files that

30:38

are larger in size and then you zip them up

30:40

and it's a smaller file

30:43

because the message

30:45

from people like me that we need this somewhere between

30:47

seven to nine hours for the average adult, the

30:51

trend in society is only going

30:53

down if you look at the sort of the

30:55

global sleep loss epidemic. And

30:58

I could continue to wag my finger and

31:00

speak about why that's detrimental and

31:03

it's probably not going to change. The genie of sleep

31:05

decline is out the bottle and I fear it's not

31:07

going back in. But what if I

31:10

could then instead work with the

31:12

trend rather than just try to be dictatorial

31:14

and push back against it? What if

31:16

I could find ways to compress

31:19

human sleep to a shorter amount without

31:21

any detriment? Now, we have never been

31:23

able to find any sort

31:25

of trick like that that truly

31:28

compresses sleep so that you get all

31:30

of the benefits and you show no sign of disease

31:32

or sickness or brain dysfunction. Beyond

31:35

sleep, I wish I could understand

31:37

something called the placebo effect because

31:39

the placebo effect is the most reliable effect

31:42

in all of pharmacology and I think it is

31:44

the most fascinating and understudied

31:47

area of science and I think it's important for

31:49

several reasons. Many

31:51

people will not realize that when drug companies

31:54

are producing making drugs that come to market,

31:56

it's fiendishly difficult and

31:58

most of them fail. Most of them

32:00

fail not always because they're not

32:02

good drugs, but because they can't beat

32:05

out the competition called the placebo

32:07

effect in clinical trials, which

32:10

tells you not about how ineffective

32:12

the drug is, but how potent

32:14

the placebo effect is. There

32:17

is such a thing as mind over

32:19

matter, and the science underlying

32:21

it that's starting to emerge is utterly

32:24

compelling. And I think if

32:27

we can harness this effect of how

32:29

we can heal ourselves, I don't mean this

32:31

in the sort of woo-woo non-science, if

32:34

we can harness that capacity of how

32:36

your brain can

32:38

heal your body through this notion

32:40

of mind over matter, or even heal

32:42

itself, and there's evidence of the brain essentially

32:45

changing the brain through the placebo effect,

32:49

what options do we have? What is untapped

32:52

there? Gosh, to me that's... Oh,

32:55

if I had a second career that's probably what I would try. That's

32:59

great. Second question,

33:02

how do you tell someone they have their facts

33:04

wrong?

33:07

Huh. Well,

33:11

I think the first thing I would do is

33:13

listen,

33:14

and then I would

33:16

try to quickly find what

33:18

about their thinking I still find

33:20

to be right, and

33:23

then I'll cross-reference

33:25

that rightness in the

33:28

full panoply of wrongness of

33:30

the statement that I see, and I'll see

33:32

if I can firstly just try to update

33:34

my own belief system. I will

33:37

begin with what's called a soft start,

33:39

and I'll begin by telling them what I

33:42

do think about their opinion resonates

33:45

with me rather than just being completely combative,

33:48

but then I will be direct and I'll

33:50

be clear about why it is that

33:52

they may be wrong, and then I'll

33:55

be constantly reading their signals, and

33:57

if I find that they are inflexible...

34:00

unable to hold that for conflicting IOS

34:05

then I'll usually just stop the purpose

34:10

you know it's not going to change anything so I

34:12

don't know if that's

34:14

a logical way of approaching

34:16

it or makes any sense but that's probably how I

34:18

approach sounds like a very practical way

34:21

third third quick question what's

34:24

the strangest question anyone has ever asked

34:26

you if

34:31

you're a sleep scientist trust me

34:33

if there are no shortage

34:35

of utterly bizarre questions I

34:38

think the best question I ever

34:41

had oh I was

34:43

in I was at a doing a speaking appearance

34:45

in Europe someone asked me if

34:48

there was a sleep Olympics which

34:51

activity did you want to compete

34:54

in and I just thought that is the most

34:56

brilliant question and I

34:58

think my answer was I would do the

35:01

decathlon because I would want to

35:03

take part in all of the

35:05

full richness the full kaleidoscope

35:08

of sleep

35:08

brilliance that I want to be doing all of those

35:10

but so I would say the decathlon

35:13

within sleep is it I just

35:15

thought that's such a good question ah

35:18

if only I could be as creative okay

35:20

next question how do you stop

35:22

a compulsive talker now

35:26

I'm thinking back on our interview and thinking I'm probably

35:29

very guilty of doing I need to

35:31

know I'll

35:35

hmm

35:36

I'll usually wait

35:39

until they say something that has a

35:41

sort of a common launch pad for

35:43

other people integrating other people

35:45

and then I'll usually say oh and Steve

35:49

can I just pause you for a second that's

35:51

such a fascinating point and

35:53

I want to see if Jessica

35:56

has had experience because I think she has had experience

35:58

in that based on that back in and

36:01

therefore I'll try to help pivot

36:03

the spotlight focus of the conversation

36:06

onto someone else and then I'll keep trying to

36:09

sort of perpetuate that. If

36:11

that doesn't work which sometimes it doesn't because

36:13

the person then very quickly boomerangs

36:15

the control back to themselves if they

36:18

are quite self-centered

36:20

and egotistical. At

36:22

that point I'll usually just

36:24

remove myself from the conversation

36:27

and that's usually what I would do in the extreme.

36:30

Okay let's say you're at a dinner table sitting

36:33

next to someone you don't know. How

36:35

do you strike up a genuine conversation?

36:38

I

36:39

think if it's a

36:41

couple that are sitting

36:43

next to me then I will

36:45

usually ask them about the very first

36:47

time that they met because I think people

36:50

so enjoy reliving those moments

36:52

of positive significance but

36:55

it also helps me very much to learn a great

36:57

deal about those two individuals but

37:00

if it's just an individual

37:02

I'll usually ask them

37:05

what attachment

37:08

do you currently have that is most

37:10

holding you back?

37:13

And it usually requires people

37:15

to stop and think for a second and

37:18

it's a very intimate question I feel and

37:20

I always tell them to say look you know

37:22

don't worry if it feels a little personal I know that's a very

37:25

direct question but it leads

37:27

them to be vulnerable with me and

37:29

that it allows me it almost gives me permission

37:32

as an unfortunate British person to be that dangerous

37:34

thing that we don't like doing which is also

37:37

become vulnerable with them. And at that

37:39

point very quickly do you deepen

37:41

a connection between two people?

37:43

Okay next to last what gives

37:45

you confidence?

37:47

Connection with other humans

37:50

I gain immense confidence yeah. Okay

37:53

last question what

37:56

book changed your life?

37:58

I think the book that really push

38:00

me into brain science was a book

38:03

called the Mind of the Mnemonicist.

38:05

And the Mnemonicist is one of those sort

38:08

of supercharged memory

38:10

individuals, the people who can't forget

38:12

anything. And I think the tagline

38:14

was a small book about a vast memory.

38:17

And it was written back in the 50s

38:19

by a neurologist called Alfred

38:22

Luria. And he

38:25

was studying people with just exceptional

38:27

memories. And the book is in some

38:29

ways a story of two halves. He starts

38:31

off thinking, I don't believe this. I'm

38:33

going to find the breakpoint of where they

38:35

just fail to be able to remember.

38:38

And I will show that they can't remember

38:40

everything. And he couldn't find

38:42

the breakpoint. These people just seem to be able

38:45

to memorize everything. And then

38:47

this was what was genius. And it taught me to be

38:49

a counterfactual scientist

38:51

or a counterfactual thinking scientist,

38:54

which I think is one of the hardest things to do.

38:56

And I will fail miserably. He then

38:58

flipped the question. And instead

39:00

of saying, what is the benefit

39:03

of always being able to remember,

39:06

he then started to say, I wonder if

39:08

there is any detriment to never

39:10

being able to forget. And

39:12

what he learned was that the lives of

39:15

these people are not lives that you and I would

39:17

wish to live, because they have

39:19

these hyper

39:20

intense memories. And

39:22

it's actually quite debilitating. And

39:25

gosh, did that teach me a lesson into

39:27

how to think about the two sides of any scientific

39:30

coin. So I would definitely recommend

39:32

that book. Well, you've

39:34

really been a treasure. Thanks

39:36

for being here, Matt. Lovely to connect.

39:45

This has been clear and vivid. At

39:47

least I hope so.

39:49

My thanks to the Caudley Foundation for

39:51

sponsoring this episode. The

39:53

Caudley Foundation is dedicated to advancing

39:56

science for the benefit of humanity.

40:00

is professor of neuroscience and psychology

40:02

at the University of California, Berkeley,

40:05

and he's the founder and director of the Center

40:07

for Human Sleep Science. His

40:09

best-selling book is called Why We Sleep,

40:13

and his podcast is the Matt Walker

40:15

Podcast. This

40:17

episode was edited and produced by

40:19

our executive producer, Graham Chedd,

40:22

with help from our associate producer, Gene

40:24

Chimay. Our publicist

40:26

is Sarah Hill, our researcher

40:29

is Elizabeth Ohini, and the sound

40:31

engineer is Erica Huang. The

40:34

music is courtesy of the Stefan Koenig

40:36

Trio.

40:46

Next in our series of conversations, I

40:48

talk with Kashmir Hill. She's

40:51

the New York Times reporter whose new book,

40:53

Your Face Belongs to Us, has

40:55

the scary subtitle, A

40:58

Secretive Startup's Quest to

41:00

End Privacy as We Know It. I

41:03

remember one photo was

41:05

a woman

41:06

in profile kind of walking

41:09

on a sidewalk in the background of someone

41:11

else's photo, and I didn't think it was me at

41:13

first until I saw

41:15

the jacket. I kind of focused on the jacket

41:18

I was wearing, and it was from an

41:20

American vintage store in Tokyo,

41:23

and I said, wow, that's me, even though

41:25

I can't even recognize myself in that photo

41:28

or remember where I was walking. It's

41:30

kind of incredible what the technology

41:33

is capable of now in terms of when it can

41:35

recognize you in a photo. Kashmir

41:37

Hill and how now everyone can

41:39

know your face, and not just

41:41

your face, next time on

41:44

Clear and Vivid. For

41:46

more details

41:46

about Clear and Vivid and to sign

41:48

up for my newsletter, please visit

41:51

alanalda.com, and

41:53

you can also find us on Facebook and Instagram

41:56

at Clear and Vivid. Thanks for

41:58

listening. Bye-bye. Thank

42:08

you.