All language subtitles for Limitless with Chris Hemsworth - S01E05 WEB.eng

I read this script once
and there was a line,

and it said, "If I don't have my memories,
did I ever exist?"

And it's always stuck with me.

Our memories are supposed
to last forever.

They're what shapes us
and makes us who we are.

Good shot, son. Good shot.

The idea that I...

won't be able to remember
the life I've experienced

or my wife...

my kids.

This is probably my biggest fear.

And recently, I had some news
that made me think

a lot more about all of this.

When I first started exploring
how to live better for longer,

I was sent for a whole list of tests...

- How you doing?
- ...by longevity expert Dr. Peter Attia.

- How you doing today?
- Doing good.

So, we did sort of
the million-dollar workup on you.

We've got every blood test
one can get

and I've looked at every gene
in your body six ways to Sunday.

And overall, your labs look fantastic.

And I think looking at you
from the outside,

it's clear how much
you take care of yourself,

but we did find a couple of things
that are a cause for concern.

Right.

Some of the genetic testing that we did

looked at a gene
for a protein called APOE.

You have a very rare combination,
which is you have two copies of APOE4,

a set from your mom
and a set from your dad.

And what does that mean exactly?

That means you have an increased risk
of Alzheimer's disease.

How much higher?

Probably somewhere between eight
and ten times higher

than that of someone
in the general population.

Yeah, all right. Okay.

You know, you're...

I don't know, you're constantly thinking
you're gonna live forever,

especially as a young individual.

And then to all of a sudden be told,

"Well, this may be the thing
that might take you out,"

was like, "Whoa."
Kinda floored me for a minute.

I know it's hard to imagine, but...

it's my belief that if we take
every step possible,

we can reduce your risk
to that of anyone else.

Mm-hmm. Sure.

In fact, I don't think you'll believe me
when I say this,

but I think you will in time.

You having this gene
is probably a blessing.

Because of the motivation
that it'll give me to...

Yeah. This is going
to motivate you to take steps today

that most people your age
would never think about

- until they're in their 50s or 60s.
- Sure. Sure.

I've spent most of my life
paying very detailed attention

to my health and wellness

and looking at how I can be, you know,
stronger and healthier and so on.

But I've never really focused
on the health of my brain.

This news changes things.

Here is a test for checking
frontal lobe function and planning.

So watch what I do first,
and then you copy me.

All right? Here we go.

That's why I'm meeting
renowned neurologist Dr. Sharon Sha.

Wait, hang on.

Was that... Just gotta see it again.

I think, like everyone,
I want to maintain my memory

for as long as possible and not be,
you know, in the corner

unable to, sort of, operate, you know.

Yeah. I mean obviously
you're really healthy,

but after the age of thirty
is when our brain starts to degenerate.

Our peak is in our youth,
or in our twenties.

So we have to enhance
and maintain as much as possible.

You can't say, "Okay, at 60,
I'm now going to focus on my brain."

Yeah. Yeah.

Because Alzheimer's disease
and other types of things

develop 15 to 20 years
before we even have memory symptoms.

I eat pretty well. I exercise a lot.

What else can I do that is going
to help improve my brain health?

Just like you have to take time
to work out your body...

Yeah.

...you've gotta take time
to work out your brain.

Novel challenges can stimulate
neuronal connections

to spread
what we call "neural plasticity,"

and that can really enhance
cognitive function.

So let's give you something novel.

Let's give you something
where you can really challenge your brain.

In order to help protect his memories,

I want Chris to take a break
from his normal life...

unplug from technology,

and go off the grid in the wilderness.

Pretty spectacular, hey?

Right there,
take a mental picture.

Without anything to distract him,
no phone, no GPS,

Chris is going to have to immerse himself
in his surroundings...

and navigate his way through
the outback

using only his brain.

Man, it's so easy to get lost out here.

Well, I'm glad you're here
because I have no clue.

I'm already lost.

And because social contact
is so important for cognitive function,

his friend, the artist Otis Hope Carey,
is going with him.

That looks like a really good campsite

at the bottom
of that waterfall back there.

So it's a good point to remember.

That's where
we're gonna end our trek.

- Right there?
- Yeah.

How are we gonna get up there?

Think of this challenge
as a boot camp for the brain,

a way for Chris to kickstart

a lifelong routine
to keep his brain healthy.

I welcome you. I welcome you
to Dunghutti country, Anaiwan country,

and Gumbaynggirr country.

It's a shared country
between the three tribes.

This is my buddy Otis's
ancestral homeland.

For years, we've dreamed about
going on a trip to explore it.

So when Sharon suggested
an adventure in the wilderness,

I knew this would be the perfect location.

What makes this place
particularly appropriate for our journey

is that in this part of the world,
landscape and memory are intertwined.

Body, mind, and spirit.

My name's Otis Hope Carey.

I'm from the Gumbaynggirr nation
and also the Bundjalung nation.

Indigenous people have been in Australia
for sixty-thousand-plus years,

so we've got a very long connection
to Mother Earth.

In First Nations culture,
we believe there's memory in the rocks,

in the water, in the wind, in the sky.

So if we sit and listen,
we can hear our ancestors talking to us.

We hope that on your journey,

you will listen to our country
speak to you.

Hear the sounds of this world
with your own ears,

not the ears of others.

See this world with your own eyes,

and not eyes of others.

As the elders are giving us
permission to walk across the land,

one of them says,

"Listen with your own ears...

"and watch with your own eyes.

"Stay true to who you are."

And it really, really struck a chord
within me and spoke to something...

...on a very deep level.
It's quite beautiful.

Over the next two days,

Chris and Otis are going
to have to navigate

through thousands of acres of wilderness.

Okay. So, this is where we're starting,

and then we head out this way, right?

But the mental challenge
has already begun,

plotting their route
and committing it to memory.

And then we hit up
on this ridgeline, right?

Yep.

First, they'll head north
over a mix of open country and forest.

From the top of the waterfall,
we come up here and we hit this creek,

and then which way are we going from here?

We change direction when we get
to this little river.

We've got to then go downstream.

They've got to find a river

featuring a series of waterfalls,

which will lead them to a place

that might make a good campsite
for the night.

So, our day two trek, from our camp...
we're going to head due north.

- You got a photo there, yeah?
- Is there a track through there,

- or we're gonna have to...
- No.

We're gonna make our own tracks.

Finally, they'll have
a steep climb towards their destination,

Wrights Lookout.

Okay, so, the route.
So forest, ridgeline, waterfall,

forest, ridgeline, waterfall.

After the waterfall,
climb up to open country, um...

and I'm going to get us lost, for sure.

Good. Well, I'm glad you're there.

But before Chris and Otis set off,
there's just one more thing.

Hand me your phones.

All right, there you go.

Thank you. Thank you. Is that all?

- That's it. That's all.
- That's all of them.

There's one more. This one.

So, who's going to find this harder?

Probably Otis.

He uses his phone a lot, so...

he's gonna have a real tough time,
aren't you, mate?

Good luck.

Rain's coming.

Do you think we're heading
in the right direction?

Just keep walking. It's the best thing
to do when you're lost, right?

A little more challenging
now the sun's completely disappeared.

Well, if we look around,
where's the brightest part of the sky?

It's there.

It's either a sun or it's a spaceship.
Tipping towards the sun.

So north, west.
We want to set ahead this way.

Yeah, I reckon.

Let's do it, mate.

There's a very specific reason why
I've set Chris and Otis loose

in the wilderness without anything
to help them navigate.

So, what do you reckon?

Is the gully over here now?
Looks like it.

Yeah, this way I reckon.

The process of figuring out
the right direction to go in

is one of the most complex tasks
our brains can perform.

Up the ridgeline, follow the water,
stream, waterfall, turn left.

Yeah, this is good.

And it relies on a region of the brain
that's critical to how we process

the world around us.

It's called the hippocampus,
the brain's memory center.

The hippocampus is
a small structure shaped like a seahorse,

located in both the left
and the right sides of the brain.

Think of it as a map of where
all our memories are stored

and how to access them.

As we age, the hippocampus shrinks,
and it's one of the first areas

targeted by diseases like Alzheimer's.

But when we stimulate it
with activities like navigation,

it becomes bigger and healthier,
as new connections are forged

and more brain cells added.

And scientists think the stronger
our hippocampus,

the better our chances of resisting
the cognitive losses that come with age.

Ditching the GPS
and navigating on his own

is something Chris can easily work into
his daily routine.

It's a simple and effective way
to keep his brain active,

which should help it stay strong
and resilient.

Okay,
so it's probably close to noon.

Yeah, I reckon.

North, east, south, west.

So that's north,
so we want to set ahead this way.

There's the river.

Oh, yeah.

I feel like we're getting closer
to where we need to be.

Jeez. Quicksand.

It's like that scene
in NeverEnding Story,

Swamps of Sadness.

Remember The NeverEnding Story?

- No.
- The NeverEnding Story. Never saw it?

- No, I don't think so.
- Otis.

I didn't get to watch
much TV growing up.

Remember those old TVs where you had to,
like, move the antenna around?

- Yeah.
- We had one of them.

Yeah, as you wouldn't...
It's not just about moving the antenna,

it was about standing
in the right part of the room.

Yeah, and also...

Yeah. "Don't sit there, Dad.

- "You'll make the TV go fuzzy."
- Yeah.

There's something very nostalgic
for me about being in nature...

so far from cities and towns
and civilization.

And when I think about some
of my earliest memories,

the ones that have shaped who I am,
those are the moments

I want to keep hold of forever.

I grew up in the Northern Territory,
right in the middle of nowhere,

four and a half hours
from the nearest town,

and I didn't own a pair of shoes
because it was too hot.

And we spent our entire time
outside, basically.

My earliest memory...

I was very young. I was probably four.

I remember, uh,

my dad going to pick
someone up from the airport,

which was a big strip of dirt,
basically, in the middle of the outback.

And I walked out looking for him,
and then just kept on walking.

I remember the dry, crackling heat.

The red dust
that just gets into everything,

your skin, your hair, your clothes.

And the feeling of my feet,
just feeling like they're on fire.

I was in tears.
I didn't know where my dad was.

But all of a sudden,
he came over the hill.

He was in an obvious state of panic,
wondering what I was doing

in the middle of the outback,
wandering around on my own.

At the time I didn't really understand
what was going on

or what his concern was.

But I remember the warmth and the comfort
of feeling safe and secure in his arms.

- Straight up?
- Yeah.

This is like the StairMaster 2000.

- You thirsty?
- Yeah.

- I'll get a drink with you.
- Yeah.

So beautiful.

You normally
would be taking a photo, and...

Not listening and...

looking through a phone camera.

Yeah.

It's amazing being here
and not distracted.

Just how all your senses are heightened.

All the smells, everything you touch,
the sound.

It's no surprise
that Chris is feeling more alert.

Our brains evolved in nature,

and there are studies that show

why we find the natural world
so refreshing.

Research suggests that when
we're in urban settings,

all the man-made visual patterns...

...intrusive noises, and distractions

take a lot of mental energy
for key parts of the brain to process.

Which means that memory,

problem-solving, and concentration
all take a hit.

But scientists think
that our brains are attuned to find

the sights and sounds of nature
much easier to process.

Instead of being overloaded,

our cognitive abilities are restored
to full strength.

And that's not all.

Spending time in nature
also lowers stress,

which is good for our Alzheimer's risk
and our longevity.

In fact, just a twenty-minute stroll
in the park

without checking your cell phone

has been shown
to significantly reduce levels

of the stress hormone cortisol.

- Sure you don't want to lead?
- I'll lead. Come on.

How about I go? Because if I slip,
it's not that big a deal.

Yes, it is. I'll have to carry you.
It'll be a massive deal.

That's what I mean,
you're stronger than me.

Otis is a great guy.

Got a great sense of humor.
He's a very kind individual.

Otis!

- Help me.
- You fell graciously, though.

Must say.

And also, he's a fantastic artist.

All your artwork
is bird's-eye view, right?

Yeah, lot of it. Yeah.

It's kind of topographical,
I guess you could say.

I use a lot of, like, traditional symbols,
but I...

sort of soften them,
make them more expressive.

Also remembering where they're from,
their true meaning.

I take old traditional art,
thousands and thousands of years old,

and modernize it.

I try and just give a new spin
on the old way.

Every line, every dot in my art...

just like every rock, every river,
every tree,

is a memory.

I think Chris growing up
where he grew up,

there's a massive indigenous community,
so he understands my paintings.

And I think that's really a big reason
why we probably get along so well.

We should've brought a canoe.

A bodyboard would've been better.

Spending time with other people
is good for our brains.

We're social animals, and interacting
with others can encourage us

to learn new things, spark new thoughts,
or ways of seeing the world.

But when we're isolated,
our risk of developing dementia

is about fifty percent higher.

So of all the things we know
that can protect our longevity,

the people around us may be
the most important.

Okay,
so if we keep heading this way,

we should get to that campsite. Yeah?

Yeah. Campsite's at the bottom
of the waterfall.

So we're at the top
of the waterfall,

and Otis is pointing out
where we could camp.

And I can't see any way down.
Neither can he.

So there's one solution.

Oh, boy!

Now you feel alive!

Well, that has definitely
cleared my head.

And it makes me think,

"I hope I'll still be dive-bombing
when I'm an old guy."

Since my test results,
I've been thinking a lot

about growing older
and what my life might look like then.

Perhaps the news I have
a higher risk of Alzheimer's

shouldn't have come as a total surprise.

My grandfather,
yeah, he has Alzheimer's.

And...

His... Yeah. His memory's deteriorating,
and has been for the last couple of years.

It's tricky because when he is lucid,
then he gets very worried

because he realizes who people are
and why... where is he?

You know, so it's... daunting and scary.

My most vivid memories of him
were sitting in the garage with him.

And him helping us build things
out of timber.

He'd build us swords,

little fake, sort of, you know, pistols
and rifles and things.

And I remember him being really patient
as we're kind of hammering and banging,

cutting things and breaking things.

I have such beautiful memories,
which I'm so, so thankful for...

of just this nurturing, kind individual.

He's a beautiful man.

So, your grandfather...
he has Alzheimer's?

Yeah. He either doesn't remember
who we are, you know,

his grandkids,
but also even his own children, you know.

Forgets. And, uh...

Yeah. It's heartbreaking.

Does that worry you at all that you...
you might end up in his situation?

Like most things that scare you,
they either shut you down

or they motivate you to overcome them
or do whatever you can to,

you know, to beat those odds, I guess.
That's what this is about, isn't it?

About... doing as many
preventative things

to ensure brain health.

There's a positive energy to it all,
as opposed to like,

"How many emails I gotta reply to?"
Or, you know,

"What review are they gonna give me
on my film,

"and am I ever going to work again?"

Today's hike
has taken it out of us,

so we decide to call it a night.

But no matter how tired I am,

winding down is often a struggle.

And sleep was one of the main things

Dr. Peter Attia focused on
when I had my consultation.

So Chris, tell me about your sleep.

Would you consider yourself
a good sleeper? A...

No, not a very good sleeper.
I wake up a lot through the night.

I remember even from a very young age.
But yeah, my mum talks about it now.

There's something about the nighttime
and sleeping would amplify

any sort of concerns, or sort of
if I felt guilty about something,

I felt like I did something wrong,
or something I was concerned about.

And that still, you know,

is definitely there.

So much of what you describe
as your limitations in sleep

seem to stem from what we call
"the monkey mind," which we all have.

The sort of neuroses,
the rumination of thought.

Sleep is not a passive activity.

It's not about being unconscious.

It's actually an active time
during which the brain is healing.

And in your case, Chris,
because of your increased risk,

we really wanna take sleep seriously.

We know that even a single night
of missed sleep

leads to some of the accumulations
of toxins in the brain

that predispose people
to Alzheimer's disease.

So sleep has remarkable
restorative powers in the short run,

but it also carries with it a lot
of protection against chronic disease.

It works like this. While we sleep,
the junk that builds up during the day

is washed away by a kind of
trash disposal service

called the glymphatic system.

But, as we age, and especially
when we don't sleep properly,

this cleanup operation gets sloppy.

Harmful waste starts to build up faster
than it can be cleared away.

Jamming up the works,

causing inflammation,
and potentially leading to Alzheimer's.

There's a lot Chris can start doing
right now

to improve the duration
and quality of his sleep.

Creating simple habits,

like going to bed and waking up
at consistent times,

reducing stress before bedtime,

and checking out of email
and social media.

That's easy when he's camping
in the woods.

But hopefully enacting these changes
when he's back home

will reap the real dividends
in terms of his future cognitive health.

And a healthy sleep regimen isn't
the only thing

that Chris should keep practicing.

Good.

In fact, many of the habits
he's already adopted

can help to prevent brain disease
in later life.

There you go!

By periodically fasting and eating
a diet rich in vegetables and fish,

he's fighting the cellular aging
that contributes to Alzheimer's disease.

Don't know whether to laugh or cry.

Taking steps
to reduce his stress levels

should also help protect his memory.

And exposing his body
to extreme temperature

has been shown to significantly reduce
the risk of Alzheimer's.

How'd you sleep last night?
It was pretty wet.

It was beautiful with the waterfall
in the background.

- Mm. Waterfall sung me to sleep.
- Yeah.

So it's day two,
and after a good night's sleep,

I feel refreshed.

I know I've only spent a day and a night
away from my phone and emails,

but already
my mind feels clearer

and calm.

And I'm excited for what's to come.

Do you know which direction
we're gonna walk today?

Continuing northwest?

Have we got any sun yet?

I reckon the sun will come out
a bit later.

We're gonna get to Wrights Lookout
hopefully in time for the corroboree.

So, where we're heading,
Wrights Lookout,

is a very special meeting place
for the indigenous people in this area,

where, in the past,
different nations would gather.

What is a corroboree exactly?
What are we expecting to happen?

Well, three nations are going
to be meeting,

and we're gonna have a dance,
and it's about sharing wisdom

- and just appreciating country together.
- Yeah.

It's about feeling connected
to something outside yourself.

For sure, hundred percent.
There hasn't been a corroboree up here

for over 100 years,
so it's gonna be really special

and it's gonna be super powerful and...

spiritually recharging.

It's starting to get steeper.

Got your rock climbing gear?

I'll give it a go.

The second day of the hike holds
a different kind of challenge for Chris.

To get to Wrights Lookout,

he and Otis have to climb up
the side of a mountain.

Although you might consider it
a workout for the body,

it's just as much of a workout
for the brain.

You look like a bit
of a mountain goat, man.

Yeah.

All that gym work.
You'd be able to carry me up there.

When we exercise,

our body produces a chemical
that acts like a fertilizer for the brain.

It encourages neurons
to grow and stay healthy.

- Getting closer.
- We're getting there.

And we know from multiple studies
that regular exercise in midlife

can reduce our chances
of getting Alzheimer's disease

by almost 50 percent.

And exercise,
combined with a cognitive challenge,

is proving to be
an extremely powerful tool

in the fight against dementia.

Even when we grow older.

My mother died five years ago,

and sadly, she suffered from dementia.

And yes, it lives with me
in the back of my mind,

good grief, it's going to happen

or may happen to me.

One, two, three, four.

Every week,
seventy-year-old Gudrun

attends a local dance class.

Sometimes I don't feel
as good as I did 30 years ago.

But mostly,

I'm in pretty good shape.

But this is
no ordinary dance lesson.

It's a scientific study.

Its purpose, to find out whether
an exercise like dancing

is more beneficial for the aging brain
than an ordinary workout.

Dancing is learning complicated movements.

It's not like sitting on a bike
where you do repetitive movements.

So we think that our dancing
is a better way to improve brain function

because it involves this combination
of cognitive and physical challenge.

Scientists have discovered

that our brains
have the capacity to grow and develop

new connections even in late adulthood.

I'm the guinea pig!

So Notger and his team

want to find out
how effective the dance program is

at stimulating that growth.

They're looking for signs
of positive change

in that region of the brain
vital for memory.

Please show me
the front part of the hippocampus.

Stop.

You can see an increase here.

It looks really good.

This was such
a big relief because our results show

that dancing has an amazing potential

in improving brain function and structure.

And we really hope that dancing
will be able to prevent

cases of dementia in the future.

It's not just Gudrun's results
which are impressive.

The dancing group showed more growth
in the hippocampus

compared with those who followed
a conventional workout.

Well, the results had
a real "wow effect" on me.

So I'm giving myself a bit
of a pat on the back,

telling myself "well done."

We've been climbing
for a few hours, and finally,

Wrights Lookout feels
within touching distance.

- Straight up here?
- Yeah.

Is this the right spot?

- Well done, mate.
- Good job.

Good job.

We've made it.

And all without a phone,
GPS, or even a map.

Just the one thing people used
for millennia to navigate this earth.

Our brains.

That's where we walked from.

- Long way.
- It is a long way.

Gives you some perspective, doesn't it?

As I look out at how far
Otis and I have come,

the beauty of this landscape,

I think about what the elder said to us
before we set off.

"Listen with your own ears

"and see with your own eyes."

And now it makes perfect sense.

If we block out the noise
and truly tune in to the natural world,

we'll live better.

It's been a long two days,

but we've made it here
for the corroboree,

the gathering.

On behalf of the three nations,

we want to invite you
to come dance with us.

- Sure. Thank you.
- Yeah.

- I'm not much of a dancer.
- That's all right!

You know, I really thought
I was gonna be just observing.

And now, I feel really nervous.

- Paddle left. Paddle right.
- Paddle left, paddle right.

Low, low, shoulder, shoulder.

All right.

There's such a beautiful welcoming
from everybody there,

and encouragement,
that I pretty quickly get into it.

And I look over at Otis,

and, uh, I start to see
what it means for him.

The meeting of these three nations.

I feel empowered.

I feel a sense of belonging as well.

Because this gathering
is to waken our ancestors

in the memories and our stories
from the earth.

Not only am I creating new
and beautiful memories...

but I get to share that with Chris,
and we get to talk about that

for the years to come.

I started this journey concerned

that I might lose my memories
when I'm older.

But I've realized just how much
of this is in my own hands.

The prescription is simple.
Eat and sleep well.

Challenge my mind and body
with new experiences,

and immerse myself in nature

away from the distractions
and stress of modern life.

And crucially, share all of this
with the people I love.

None of these simple acts
are bitter medicine.

They're things I love to do anyway.

Things I want to do more often.

And hopefully, I'll not only live
a happier and more rewarding life,

bringing joy to my family and my friends
just as my grandpa did,

but together we'll forge
precious new memories

that will live with me
for the rest of my life.