Original subtitles

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.