All language subtitles for The.UnXplained.S08E02.Nightmares.and.Dreams.1080p.HULU.WEB-DL.AAC2.0.H.264-RAWR_track3_[eng]

Terrifying nightmares

linked to inexplicable deaths.

Unconscious visions

that foretell
of unspeakable tragedies.

And emerging technologies

that can engineer
our wildest dreams.

Just like breathing,
everyone dreams.

We might not always remember it,

but it happens every night
of our lives.

Some believe our sleeping
thoughts are nothing more

than nonsensical concoctions
of the mind,

while others claim
our dreams and nightmares

could be messages from beyond,

premonitions of the future,

or even secret signals

that have the power
to transform mankind.

Could there be more
to our subconscious stories

than we realize?

Well, that is what
we'll try and find out.

It is said
that the average person dreams

between one
to two hours per night,

which adds up to about six years
over a lifetime.

And while it might be easy

to dismiss
these involuntary images,

thoughts and sensations
that are conjured during sleep,

it's clear that dreaming is
as hard-wired

into the human experience
as breathing.

Yet, the meaning and purpose

of these enigmatic
mental expressions

remains one of
the longest-standing mysteries

of the mind.

Throughout history

and cultures
all around the world,

people have turned
to their dreams for reassurance,

wisdom, guidance and warnings
of dangers to come.

People generally agreed

that dreams are valuable
and important.

There's something about
the intense visual qualities

of dreaming.

We are asleep.

And yet,
our imaginations can create

these marvelous
visual experiences.

Dreams hold so much influence
over humans

because they're just inherently

a dramatic,
attention-grabbing experience.

And in some cases,
are very fantastic

and surreal and adventurous.

They just inherently grab us
from childhood onward.

You've had experiences
that didn't really happen,

but it's a piece of your life.

It appears
we've been trying to make sense

of what happens when we slumber
since the dawn of civilization.

The first documented dream
was recorded

in 2500 BC in Mesopotamia.

The Egyptian Dream Book--

written on ancient papyrus
over 3,000 years ago--

compiled 108 different dreams
and their proposed meanings.

And in all this time,

we've yet to answer one
very basic question.

What is the purpose of dreams?

There's a lot of disagreement
among dream researchers

about why we dream,
whether dreams have any meaning.

People will speak of God.

They'll speak
of evolutionary wisdom.

Sigmund Freud was
a medical doctor

and psychiatrist
in Vienna, Austria,

who, in 1900, published
The Interpretation of Dreams.

And in this book, Freud taught

that dreams are the royal road

to a knowledge
of the unconscious mind.

By studying our dreams,

we learn about
the deepest wishes and desires

and fears and instinctual drives
within each of us.

Some of the theories
about what happens

while we're dreaming

is, we're consolidating
our memories.

Being able to take all
of these different things

that have happened to us

throughout our lifetimes

and create
a coherent self-identity.

That that's where our sense
of self comes from.

Is that true?
We don't know.

Inside this century-old hospital

lies the Dream
and Nightmare Laboratory,

one of the few facilities
in the world

trying to reveal

what is really happening
while we sleep.

The Dream
and Nightmare Laboratory

was founded in 1991.

And we're really trying
to form links between

what's happening during sleep
and during dreams.

In the sleep lab, we measure
these through brain activity

and eye movement activity
and muscle activity.

You go through
four different stages of sleep.

And when we first fall asleep,

that's called stage-one sleep.

This stage is very short.

Even in stage one,
people will have dreams.

Then someone descends a bit
further into a stage-two sleep.

They also will have dreams

that can sometimes be mundane
or thought-like.

And then they descend
even further

into a deeper stage:

stage-three sleep.

Dreams are very vague

and very hard to recall
when people wake up.

And then, stage-four sleep,
the deepest state of sleep,

where finally
you enter REM sleep,

rapid eye movement sleep,

which is really
the main stage of interest

for a dream scientist.

The brain practically wakes up.

We have more activation
of emotional areas of the brain.

The eyes are moving,
the muscles are twitching,

and people are usually
in very vivid and elaborate

and wake-like dreams
in this stage.

Let's say dream science
has uncovered, like,

25, 30% of what's going on,

but there's still
a lot to learn.

Like, 70% is completely unknown.

It's actually very,
very difficult to study dreams

because we do not have
direct access to them.

Oh, here we got some
eye movements. -Yeah, there.

So, in all
of our scientific studies,

we wake people up, sometimes
repeatedly during the night,

so that they can report
some of their dreams.

- Sit up when you're ready.
- Okay.

But probably 95%
of dream activity

is still completely forgotten.

Apart from scientific curiosity,

you might wonder,

why should we even care
about dream research?

Well, many of mankind's
greatest ideas and innovations

are said to have been inspired
by brain activity during sleep.

There are many great minds

whose dreams have helped them

to formulate some
of their greatest work.

So, for example, Russian
scientist Dmitri Mendeleev,

actually dreamt
the periodic table.

That's the table
of all the elements.

Einstein claimed that dreams

helped him to realize
the theory of relativity,

and how the observer
perceives time and space

according to where they are.

The Google search engine, uh,
was invented in a dream.

Larry Page describes
that he woke up from a dream

and immediately started
scribbling out a plan

that was to list and rank
all Internet sites.

But there are breakthroughs
in every field of endeavor.

Another example

would be Paul McCartney's song
"Yesterday."

He dreamed that he was listening

to this just beautiful
piece of music,

and he persuaded
the Beatles to perform it,

and it became
their all-time hit.

Famous people
like Edison and Tesla

really wanted to access
the creative sleep state

as you're falling asleep.

They thought
that was the kind of key

to creativity and invention.

And so, they developed
this steel ball trick

where they would hold
a steel ball in their hands,

and then, as they fell asleep,
as their muscles relaxed,

the steel ball would drop,
and it would wake them up.

And then they would record
whatever that creative,

imaginative idea and dream was
that had happened.

What these stories
of creative insights

and inventions through
dreaming tells us is that

if we devote ourselves

to a task, to a challenge,
to a problem,

and we throw ourselves at it,
our dreams will help us.

And I think that that if
you can tap into that resource,

nothing will stop you.

Could a better
understanding of dreams

help us unlock our greatest
innovations and achievements?

Perhaps.

And as scientists continue

to probe
our sleeping subconscious,

what might be revealed?

Dream science is still seen
as peripheral and weird.

But your dreams 15 years out

can predict the onset
of Parkinson's.

But nobody knows that.

Your nightmares are a huge part

of post-traumatic
stress disorder.

Nobody's asking questions
about that.

We are dreaming
in every stage of sleep.

This is a lot
of your lived experience.

You wouldn't walk around all day
just ignoring your thoughts

and saying, "Oh,

those don't have
any influence on my behavior

or my emotional well-being."

But that's what
we're doing at night.

But dreams are in touch with
more than the science can see,

and that is fine with me
as a scientist,

and makes it
so much more interesting

to work on as a challenge.

In a working-class section
of the city,

a quiet yet unsettling epidemic
starts to unfold.

A group of young
Southeast Asian immigrants

belonging to an ethnic group
known as the Hmong

succumb to a truly
nightmarish fate.

They are dying

in their sleep.

In January of 1987,

the L.A. Times published
an article about

over 140 Hmong men
dying in their sleep

with no real explanation.

The CDC did autopsies
on the individuals,

they couldn't find any reason

on why these individuals
passed away.

There was no sign
of a heart attack or a stroke.

They were young,
they were healthy,

they didn't have prior
existing health conditions.

Looking at the surface
of the story,

there's no reason
for these men to have died.

There's still a lot
that we don't understand

about why this happened.

But one thing that's really
interesting about these cases

is that a lot
of these men reported

that in the days
preceding their death,

they were having
terrifying nightmares.

It was really a mystery.

Public health
officials coined the term

"Sudden unexplained
nocturnal death syndrome"

to at least categorize
these bizarre deaths,

but it doesn't
explain the cause.

And it certainly begs
a truly haunting question.

Could bad dreams
actually cause healthy men

to suddenly die in their sleep?

According to Hmong culture
and belief, nightmares can kill.

In the Hmong tradition,
dream is how the spirit world

and deceased
communicate with the living.

And so, they come to us
in our dreams,

and they communicate their needs
and how they're doing.

There are many spirits.

There are good spirits
and evil spirits.

The poj dab pob,
for example, are evil spirits.

So, dreams are a place
to receive communication.

Uh, however, if you don't
listen to the spirit,

it can come to your nightmares
and kill you.

This is
something which is not unique

to this particular population.

Um, in East Asia,

for instance,
there was a strong belief

in a creature
that could invade dreams

known as the Leyak.

The term "nightmare"
has its own origin,

and it comes from
this supernatural creature

in East European tradition
called the mara,

that could shape-shift

and enter into the dreams,

and could even
bring about death.

Demonic entities
and evil spirits

that prey upon their victims
in the dream world

can be found in folkloric
traditions around the world.

But what is so confounding
about the nightmare deaths

that ravaged the American
Hmong community in the 1980s

is that, inexplicably,

these men all seemed
to experience

the same horrific dream.

There are some men
who survived,

and they shared with us

that they had nightmares
for many nights in a row.

They would see
these evil, dark figures

come and sit on their chest,
that would suffocate them

and kept constricting their body
so they couldn't breathe.

They could not scream,
they could not move.

Spouses of-of the men
who passed away

shared similar stories.

So, we believe
that in these dreams,

evil spirits
called the poj dab pob

was visiting the person,

causing the sudden,
unexplained death.

Was the same
supernatural entity

really squeezing the life

from these men
in their nightmares?

The Hmong community
certainly believes it's true,

but how might
the scientific community

try to interpret
this phenomenon?

This reminds me a lot
of other phenomena

that we've studied, such as,

in sleep paralysis,
a specific type

of usually very terrifying
dream experience

that happens right at the onset
or the offset of sleep,

and most of our body
is paralyzed.

And often,
people will hallucinate

some kind of threat
or menacing figure

suffocating them
or sitting on them.

There's some thought
that these could be related

to some extreme form of, um,

sleep paralysis or night terror
that occurred to these people.

I'm not sure that's the case.

Not all of the men died,
necessarily,

of the same exact
physiological process

with the heart
or some other part of the body,

so it makes it
all the more likely

that whatever triggered
their actual dying

was something,
as strange as it might sound,

psychological or even spiritual.

And it sure sounds like
some kind of dream phenomenon.

But how could something
kill you in your dreams?

Could psychological distress

have been the cause
of the nightmare-induced deaths

of around 140 healthy men?

Some believe
it's a distinct possibility,

based on the shared experience
the Hmong had

in their war-torn homeland.

In 1954, the United States CIA

recruited them
to fight against communism

during the Vietnam War.

Ten percent
of the Hmong population

passed away during this war.

And after the United States
left the war,

the Hmong became
enemies of the state

and they were persecuted.

To escape genocide
from the communist government,

they then fled
to other countries,

like the United States.

These men had just survived
a devastating war,

so they were going through
a traumatic,

traumatic time in their life.

Was psychological trauma

from the Vietnam War

connected to these inexplicable
nightmare deaths?

All we can do is speculate.

But strangely,
by the late 1980s,

these unexplained deaths
all but stopped.

And the Hmong believe
it proves this phenomenon

was a matter of spirituality.

As these men were dying,

it was a crisis
in the community.

They didn't know
what was going on,

and so, it took elders
and shamans coming together

and talking to the spirits
to have a better understanding.

And the spirits shared
that these men

were not honoring the spirits
like they had done in the past.

When they came to America,

they were no longer building
an altar to pray to them,

offering animals as sacrifices
to honor and feed the spirits.

So, the spirits were then angry
and causing harm to the living.

Since then, we recognize
that we have to continue

making sure that, um,
the spirits are being honored

as well as, um, supported.

And so, that helped reduce
the number of these deaths.

But we believe that nightmares
still kill even today.

The mere suggestion
that a nightmare can kill

is profoundly disturbing.

It really makes the thought
of dying in your sleep

a bit more unsettling,
doesn't it?

Perhaps less alarming

is the notion
that while we slumber,

our brains may be able
to open a window

and allow us
to predict the future.

Nestled in the hills
of the Peloponnese

lies one of the ancient world's

most remarkable
medical sanctuaries

that has been preserved
for over 2,000 years.

Today, it's a UNESCO
World Heritage Site,

but in the time
of Classical Greece,

it was something more.

A sacred destination
for pilgrims to be healed

in their sleep.

Thousands of years ago,

people were dreaming in temples,

and these were specifically
for healing.

One of the most famous ones

is the Epidaurus,

where people would try
to have dreams

of the Asclepieion,
the serpent god

who would come down
and heal you in your sleep.

And so, people would sleep
surrounded by these serpents,

and they would ask
for a dream visit

from the healing serpent god.

Asclepius
is the Greek and Roman god

of healing through dreams.

You go to his temple,
really, not for diagnosis.

You go in hopes of a sacred
experience of healing.

And we have testimonies,
I mean, written reports,

of what happened
in the Temple of Asclepius,

and they're quite fascinating.

We see people who believe

that they've been healed
of specific physical symptoms

after interaction
with a sacred being.

In the ancient world,
many believed that dreams

offered more
than spiritual guidance.

One of the most
influential voices of the time

argued that dreams
could diagnose illness

from deep within the body.

One explanation comes from

the most renowned physician
of the ancient Greek world.

Galen was the personal physician

of Marcus Aurelius,
the Stoic emperor.

He wrote a number of treatises
on diagnosis through dreams.

And he said
that the reason why dreams

can give you
an accurate diagnosis

of what's going on
through the body

is that there's some function
of consciousness during sleep

that may travel through the body

and bring back
a really exact report

of what's going on
inside the body.

Today, nightmares or visions

that seem to foreshadow disease
before physical symptoms appear

are known as prodromal dreams.

But is this phenomenon
real or imagined?

As night begins to fall
over her suburban home,

43-year-old
Kathleen O'Keefe-Kanavos

heads upstairs to go to bed.

And as she drifts off to sleep,

she is visited
by a strange messenger.

I had gone in
for my yearly mammogram,

and I had gotten
a clean bill of health.

And that night,
I had the strangest dream.

And all of a sudden,
my dream froze

like, like the page
on your computer freezes.

And in the middle
of that frozen page

was a door.

And through that door

walked a Franciscan monk--
in the brown robe--

and this monk took my hand,

put it right on my breast,
and said, "Do you feel that?"

and I said, "Yeah."

And he said,
"That's breast cancer."

You go back
to your doctor tomorrow

and you tell him
you need exploratory surgery

to find this cancer.

Was the arrival
of this strange visitor

simply a figment
of Kathleen's imagination?

Or did she experience
a real prodromal dream?

An accurate assessment
of her health

delivered during sleep?

Whatever the case,
Kathleen was convinced

it was all too haunting
to ignore.

I said to the doctor,

"I need exploratory surgery
to find this breast cancer.

I know I have it.

I need you to do this.

I'm not leaving without a yes."

And so, long story short,

I had the surgery,

and when I first woke up,

I was told that, yes,
it was breast cancer.

My first reaction was,
I just started crying.

"Well, thank goodness

they found that cancer
early enough."

And so, the monk was right.

Was Kathleen's dream
a miraculous coincidence,

or proof that
the ancients were right,

that dreams really do
have the power

to diagnose and even heal?

This doesn't make sense
of the typical,

traditional, modern,
Western medicine.

And yet, it does make more sense
if we think of dreaming

in its traditional
healing capacity,

as giving us insights
into these kinds of

illnesses and problems.

The mysteries of dreaming

involve our rediscovering things
that earlier people knew,

things like
the healing power of dreams.

I think there's something
in the idea that

amongst all the things
going on in dreams,

dreams can be body talk,

and the message may come
veiled as a messenger

who has our best interests
at heart.

We've been taught
that a dream is just a dream.

You don't really need
to pay any attention to it.

It's just the mind
firing off neurons

when you're asleep.

But I've always said
it has to mean something.

I'm not really sure why
I listened to that monk

other than
it was such an odd dream.

But if I had not believed him,

I believe I'd be dead today,

and you wouldn't
be speaking to me.

If dreams do, in fact,
have the power to heal,

then telling someone
they'll feel better

after a good night's sleep

may have a deeper meaning
than we think.

And there's growing evidence
that dreams

can influence our waking lives
in other ways as well.

Because researchers
have developed a technology

that allows people
to unlock new potential

as they sleep.

This esteemed university has
produced remarkable innovations

in computer technology,

pioneering work
in medical imaging

and advanced robotics.

But recently,

MIT researchers have been
developing technology

to quite literally
engineer our dreams.

Dream engineering

is a pretty new field,

under a decade.

And what it means is if we took
all these technological advances

in sensors, devices, in A.I.,

and we aimed them
at dream science,

how can we help people shift
what they dream about

to better themselves
the next day?

Historically, the way
that people tried to determine

whether they could
control a dream is

they'd show you a stimulus,
maybe a scary film,

and then you would fall asleep.

And then they'd wake you up,
maybe four hours later,

eight hours later, and they'd
say, "What'd you dream about?"

Well, you'd say,
"I have no idea."

And the really simple shift
that we made was,

we said, "Let's focus on
the whole sleep onset period."

It's where your imagination
starts turning into pictures.

Where you're dreaming,
but you can still hear

the outside world around you.

That's when we try to slip
something into dreams.

If we can control
a small piece of a dream,

then we can run a controlled
experiment on a dream.

Can technology really control

the content of our dreams?

Well, in 2017, that's exactly
what Adam Haar Horowitz

and other researchers at MIT
tried to find out.

And they would create
a groundbreaking

glove-like device
known as Dormio.

This is the Dormio device
that we built at MIT.

This device
is a research prototype.

It works really well in the lab.

This is not built
for consumers at home.

The way this will work
is we put this on

before someone goes to bed.

You have these sensors.

This person's sleep
will be tracked,

and then Dormio looks
for a special moment in sleep

where dreams are beginning

but you can still
hear the world around you.

In that special moment,
that device will talk to you.

"Remember to think of a tree,

remember to think of a fork,

a volcano, Beyoncé," your pick.

And we found that 92%
of people who came in

would have a dream
where directly they would report

the thing that we suggested.

We're hitting this 92% number,
which feels pretty exciting,

and feels like it opens up a lot
of ground for new experiments.

Will dream technology
such as Dormio

one day allow us to live out
our wildest fantasies

while we sleep?

Climb to the summit
of Mount Everest?

Win the World Series
with a towering home run?

Or fly to a galaxy
far, far away?

It's certainly
an enticing prospect,

but how can shaping our dreams
when we first fall asleep

actually help us
while we're awake?

Right when you fall asleep,

the brain is, uh,
what we call "hyperassociative."

And it's kind of like
creative thinking,

that you are making links
between concepts

that you don't normally link.

Recently, there was a study
where they had people

try to do these
hard-to-solve math problems.

They found if people
fell asleep for just one minute,

they were almost three times
more likely to suddenly come up

with the hidden solution
to these problems.

Dormio
is designed to help people

access that state
as you're falling asleep

to try to extend
that period of creativity.

So, imagine
that you are dreaming

about flying, uh,
above the clouds.

And the researchers say,
"What were you dreaming about?"

and you say, "I was
in the clouds and I was flying,

but I had this incredible
contraption, this new way

of being able to paraglide
through the clouds."

And the researchers
play audio about paragliding

and clouds and flying.

And then you fall asleep again,

and extend the dream

so that you start
to develop more of it.

And now you're able
to describe that invention.

We can boost
creativity, we can improve

somebody's learning

just by playing
the right bedtime story,

maybe in a foreign language,

which helps them
learn French faster.

That's a study.

How well you learn something

with a 10X difference
is dependent on your sleep

and your dreams.

Devices like Dormio

could have a profound effect
on creativity and learning,

but studies have also revealed

an even more astonishing
application

for dream-shaping technology.

It may have the power

to save millions of lives.

We know that 80%
of people with PTSD

will have recurring nightmares
of the same topic every night.

These are really high stakes

because we know
that if you have nightmares,

it increases your likelihood
of attempting suicide by 4X.

So, if you're working
with folks who are,

for instance,
post-combat veterans,

and they struggle
with suicidal ideation,

one of the most surprising
results that we've gotten

is that just by having people
choose a dream,

instead of whatever
difficult dream comes naturally,

when we follow up a week later,

they significantly reduce
their suicidal ideation.

That just a shift
in the dream landscape

can shift
their waking thoughts so much

has been a big surprise
and, also, uh, really moving.

What happens if at scale,
the three million people

who are struggling with those
specific kinds of nightmares

suddenly aren't scared
to go to bed at night?

The exciting thing
about dream research

in the next ten years
is it being applied,

and the implications for
mental health and for learning.

How would that change the world?

Psychologist Dr. Keith Hearne

monitors a test subject
who has achieved

rapid eye movement sleep,
or R.E.M.,

a mental state when dreams
are at their most vivid.

Suddenly, his test subject
performs a series

of predetermined eye movements
similar to Morse code

and successfully communicates,
"I'm dreaming."

This experiment provides
the first verified

scientific evidence
of a phenomenon called

lucid dreams.

Lucid dreaming
is the kind of rare brain state

when you know you're dreaming
and can steer that dream.

It's kind of this
magical space where

it seems like
anything is possible

and that heightened state
of awareness

is a really extraordinary one.

But lucid dreaming
is a more rare occurrence.

There's probably a reason

that we don't enter
into lucid dreaming every night

and that not everybody
enters into lucid dreaming

and that it's a rare occurrence.

Usually,
lucid dreamers can control

the dream content
to some extent.

And so, we really want
to better understand,

how are lucid dreamers
able to do this?

We found that lucid dreams
are very useful

in the treatment of nightmares.

Lucid dreaming can also be used

to practice real-world skills.

Athletes and musicians can use
the dream world to practice,

say, snowboarding or playing
their musical instrument.

Or someone
who's writing a novel,

they could enter into
a lucid dream and actually

engage with one
of their characters.

So, there's a lot of different
uses to lucid dreaming,

and-and that's why
we study them.

Could lucid dreams
provide the next stage

of personal awareness
and growth?

Perhaps.

Yet, the problem is,
as little as one percent

of the population experience
lucid dreams on a weekly basis.

But what if we all had access

to a device that could trigger
this powerful state?

There's a new
tech start-up called Prophetic,

and they're working on

an idea of a head-worn device
called the Halo.

And the idea is to blast

focused ultrasound
into your brain

and to activate it
while you're asleep.

And their hope
is that that would make you

more likely
to have lucid dreams,

because in lucid dreams,

that part of your brain
is more active.

But so are other parts
of your brain.

So, they have a really
hard job ahead of them,

but I am totally excited
to see more people

entering into
the dream tech space.

If we could all
gain access to lucid dreams,

when the conscious and
subconscious mind seem to merge,

will we be able to not only push

our understanding
of dreams farther

but also, finally answer
the most elusive mystery:

why do we dream?

We tend to depreciate dreams

and treat them
as irrational nonsense,

but dreams reflect
a profound source of wisdom

that is very closely correlated

with people's most important,
uh, emotional concerns,

uh, and interests
in waking life.

But it's something that we just
haven't quite figured out yet.

We should stay open
to the possibility

that the state of dreaming
may give us access to ourselves

and an understanding
of ourselves in ways

that have never before
been thought possible.

There's been a lot learned
over the past couple of decades,

but it's still, in many ways,
a science in its infancy.

Whether it's glimpsing
future events before they occur,

healing the body

or learning entirely new skills,

dreams seem to be far more
powerful than we may think.

But as science continues

to delve deeper
into the mystery of dreaming...

...what else might we discover?

Could we unlock hidden powers?

Or open a new door
to a world of nightmares?

Pondering these questions

will no doubt keep
many of us awake at night

for a long time to come,
because for now,

they continue to remain...

...unexplained.

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