01x06 - React

[bunniefuu]

- The human body

is full of systems.

Some protect us

others nourish us

or keep us moving

But there's one system

that controls all the others

and it might be the one

that truly makes you

you

the nervous system.

To put it simply,

it perceives the world

and tells you

how to react to it.

Should you jump

run eat

shiver cry?

It makes all of those

split-second decisions.

And it also creates emotions,

ideas, and memories.

Altogether, it's one

incredible machine

that never stops reacting.

We're about to take a trip

through an astonishing universe

that lives right inside

our bodies

to uncover the systems

that make us human.

It sits inside the skull

in total darkness

three pounds of

grayish-white matter,

the consistency of tofu.

It's more than 80% water

with a little fat

and a little protein.

The brain.

Mission control

of the human body

and the nervous system.

It's in charge of how

we react to everything.

The brain is pure

processing power,

connected to a giant network

of nerves and fibers

that work in perfect synergy

to turn data to action.

Especially

when life comes at you fast.

-My name is Iman James.

I'm 29 years old,

and I am an amateur boxer.

-There are few sports that

challenge your nervous system

quite like boxing.

I mean, think about it.

In a fraction of a second,

you got to process

your opponent's move

and react to it.

If you're not quick enough

you definitely feel it.

But as furious

as the action seems

outside the body

an even more high-speed dance

is occurring every moment

on the inside.

See, the nervous system

is made up of highly specialized

cells called neurons

that send signals

at hundreds of miles per hour.

-Neurons are the building blocks

of the brain.

They are the parts

that actually make you think

decide

imagine

see things or listen to things.

-Neurons don't look

like other cells.

Most cells are compact

and round,

but neurons, they look more like

the roots of a flower

with strands that branch out

in every direction

to connect to other neurons

so that they can pass

information back and forth.

There are 100 billion of them

inside the brain,

with millions more snaked

throughout the body.

But what really makes

them ingenious

is that we can train these cells

to do almost anything

and in the process, completely

transform who we are.

-Everyone can box.

You have to kind of push aside

that self-doubt at some point,

and once you accept that,

you're like,

"Oh, what I become

is entirely up to me."

I am a teacher.

I teach middle school

and high school math and health.

I became a teacher because

I wanted to fulfill

some sort of need in kids' lives

to push them to be better.

I want my students to know

they can do anything they want.

A lot of people

make the assumption

that boxers come from, like,

the hard knocks of life,

that you have to be

really rough, maybe even angry.

I never got into a single

physical fight as a kid.

I started boxing to lose weight

in college.

I just totally fell in love

with the sport.

Anytime I was hitting something,

I was like, "Oh!"

It was like endorphins

all the time.

That's what makes boxing

so intoxicating.

-Being a boxer isn't just

about landing a punch.

It requires

extreme mental agility.

And it all begins with sight.

Everything we see starts

- light.

When light particles enter

the eye

through that black hole

at the center

they make their way to the back

wall of the eyeball

where they hit

a thin piece of tissue

called the retina.

The retina has millions of tiny

receptors called rods and cones,

which absorb the light particles

coming in

and send them back as something

the brain can use:

electricity.

These electrical signals travel

to the optic nerve

and onto the brain.

Impulses are kind of

like Morse Code,

and the brain takes that code

and turns it into your reality.

-The amount of compression

of data

that happens between the retina

and the optic nerve

is the biggest amount

of data compression

that we've really

witnessed in biology,

and it's right here in our eyes.

-Every second, the eye transmits

10 million pulses to the brain

at a speed of

270 miles per hour.

Then just as quickly,

the brain has to react.

So a boxer sees a punch coming.

That info zips to the brain,

then a conversation happens.

Should I duck or knock her out?

Like any decision, it's about

weighing the options.

Maybe the boxer has a memory

of being punched before

or maybe this is

a brand-new experience.

Either way, in an instant

the brain makes a call,

and a host of neurons

begin firing.

-Neurons in the brain

communicate through electricity

and through releasing chemicals.

At the end of a cell

is a synapse

and it's the small space

between neurons.

So the first neuron releases

a chemical substance

that's detected

by the second neuron

which then continues

that electrical activity.

You can say it's a mixture

of a lighting storm

and a chemical storm.

-Our brain sends new impulses

across our body

triggering

just the right muscles

to react.

-The first time I sparred,

I almost, I swear to God, died.

We did three 2-minute rounds.

It was the longest six minutes

of my life

and it was hard

and I got hit a lot,

but I knew what I needed

to work on,

and that's what

this sport is about.

-One of the most remarkable

things about the brain

is how adaptable it is

with a little practice.

-So a boxer, like most athletes,

carry out the same movements

repeatedly over and over.

And the more and more you do it,

the brain learns,

and it gets encoded

into muscle memory.

-PJ has been my coach

since 2015.

Hitting the pads with PJ

does a lot to help me prepare.

Helps me to work on timing,

on defense,

on footwork, combinations.

What we're trying to get to

is perfection.

Obviously that doesn't

really exist,

but if you're not striving

for it, then what's the point?

-The more you practice

something,

the more somehow

your brain changes.

This is called neuroplasticity.

-This system is pretty flexible.

Every single neuron in the brain

can form up to 10,000

connections with other neurons.

And those links change

based on the things

that we do most.

When a boxer learns

a new move

the pathway is temporary,

forged by chemicals

surrounding the neuron.

But as she practices

day in

day out

those chemical changes

become structural.

Over time, neurons will actually

change shape

and shift their position.

And as the pathway

gets more fixed

connections between different

brain regions strengthen.

-Since I first started fighting,

I've definitely gotten calmer

in the ring.

Punches come to me

and I'm not overreacting.

When I'm fighting,

time disappears.

I don't even have to think,

but instinctively I'm moving

and evading those punches,

and it takes no effort

when the mind and body are one.

-It's astonishing to me

just how adaptable

our brain can be.

By practicing things we want to

get good at, we do get better.

We do lay down the neural

frameworks

to be able to improve

ourselves at certain tasks.

That mechanism of transmitting

those, what we call

actual potentials,

from one neuron to another

is the basis of how information

is transmitted in our body,

is the basis of computation,

and is the basis of memory

in our minds.

-A memory is just a group

of neurons

having a familiar conversation.

So as we learn a new skill,

we're forming a stronger

and stronger memory

of how to accomplish that task.

Skills that require us

to use our muscles

like sinking a basket,

playing the piano,

or tying a shoe, can be

locked into our memories

for a lifetime.

Hence the saying,

"It's like riding a bike."

But other memories,

like faces and names,

can fade over time

as we need them less.

Our neurons forget

how to make those connections.

There is one way a memory

tends to stick around

and that's when there's a

strong emotion attached to it.

In fact, emotions and the

nervous system go hand in hand.

The nervous system is in charge

not only of processing

our emotions,

but deciding

how we react to them.

But sometimes, emotions

are so strong

that they overload the system

with life threatening

consequences.

-

-We are following the path

of Hurricane Maria

now battering Puerto Rico.

-The hurricane is doing

incredible damage

to a country that really is not

in any shape to withstand it.

-In September 2017,

a category 5 hurricane

descended upon Puerto Rico.

Magaly Rodriguez lived

with her two daughters

on a remote stretch

of the island.

She was about to live

through two kinds of hell

The storm itself,

and fear shutting down her body.

-

-Fear is a very powerful

protective mechanism

for us as people.

It's an enormously powerful

adaptation

to helping us internalize

a threat

and then be able

to respond to it

hopefully before the threat

catches up to us.

-Inside the brain,

you find one region that really

controls the fear instinct.

It's an inch-long

almond-shaped bulb

called the amygdala.

When we're faced with

a dangerous situation,

the amygdala sounds an alarm

setting off a chain of events.

A c*ck of hormones

courses through the body.

Pupils dilate to take

in more light.

The heart begins

pumping blood faster.

And that blood is rerouted

from less essential organs

to higher priority ones

like leg muscles

that can kick or run.

That's why when you're scared,

you get butterflies.

Blood flow to your stomach

dramatically slows down.

It's also why you get

the chills,

with less blood in the skin

to keep you warm.

All of these changes

are preparing you

to react to the threat

by either standing your

ground or running for your life.

-The fight or flight

response is ancient.

In humans, it's similar to how

it is in other organisms.

It's what happens when you are

faced with a sudden danger

or something that alarms you.

-But danger is usually

more complex

than just fight or flight.

And when you're staring

at a crisis, fear,

and how your brain

interprets it,

can quickly become

the greatest threat.

-

- Sometimes during

extreme stress,

the fear response takes total

control of the mind and body.

We end up completely paralyzed

by our own emotions.

It's a phenomenon known

as the amygdala hijack.

The parts of the brain that use

logic and reason

shut down completely.

No signals can reach them.

The impulses go straight

to the amygdala,

which runs totally

on instinct and emotion.

When this happens, you might

experience an unwarranted

outburst of anger

or become frozen in fear.

-

-Magaly's fear response

left her powerless

when her daughters needed her

to be strong.

She was determined to never

let that happen again.

-When fear goes too far,

if fear becomes

the dominant sensation

that we experience as humans,

that can prevent us

from taking on new challenges

and potentially growing.

-But how our brains react

is actually up to us.

We can learn to control fear

by making it more familiar.

That's why now

Magaly is training

to become a first responder.

She's about to take part

in a disaster rescue drill

that will put her fear tolerance

to the test

so she can learn to quiet

her amygdala's alarm bells.

-We can train different parts

of our brain to turn on and off.

There's a huge component

of biofeedback, of thinking,

of breathing

that can really help us.

-

-

- Blood

smoke

screams.

-All meant to flood the brain

with stress.

But that's the whole point.

It's mental boot camp.

Just like how we can improve

our muscles' speed

and strength with practice

we can do the same

with our emotions.

-When we expose ourselves

in small, controlled doses

to the things

that make us stressed,

we can build resistance.

Our anxiety tolerance goes up,

and the amygdala can work

to our advantage.

-The amygdala is a beautiful,

beautiful structure

because that's where

a lot of memories,

especially emotional memories

are stored.

It stores not only negative,

but also positive memories.

-If we can train our brains

to remember

how we handled

the stressful situation,

the amygdala will recall

that stored memory

in a future moment of fear

and allow logic and reason

to stick around.

-Your nervous system actually

has all the tools it needs

to keep you calm

during stressful situations

You just need to know

how to activate them.

- We essentially

have two branches

of our autonomic nervous system,

the sympathetic nervous system

and the parasympathetic.

Now, sympathetic nervous system

is our fight or flight response.

Too much of this stress response

is not a good thing,

and that's when we need a kick

in our parasympathetic

nervous system.

This is the part of your body

that's going to help you

basically do all the maintenance

things such as digesting food.

Being able to activate your

parasympathetic nervous system

a little bit more

is a good thing,

and people can do this when

they're in a stressful situation

that might fire

their sympathetic nervous system

by taking a step back,

calming their anxiety,

calming their stress,

taking a deep breath.

And trying to get a little bit

more in tune

to what the situation is.

-The types of stimuli

that we expose ourselves to

repeatedly

become the kinds of stimuli

that we become masters

eventually at dealing with.

-We're still discovering day

by day how the brain works.

The brain is made up of so many

complex pieces

working all the time

all together

to achieve the things

that you want to do.

The most interesting part for me

happens in the brain

and its communication

with the spinal cord.

-The spinal cord is like

a super highway

that connects the brain

to the rest of the body.

This thick bundle of cables

has 31 pairs of nerve fibers

that branch out

to our extremities

The way it's laid out allows

the brain to interact

with every organ,

muscle, and cell.

-All these neurons are

all interconnected

so they can all talk

to each other

and through this

very important network

we are able to constantly sense

what is going on

in the outside world.

-From our little pinky toe

to our brain,

our body uses a system of

communication in our nerves

that's a lot like digital data.

We store information as almost

like ones and zeros,

pulses of voltage

that represent information.

- Together,

the brain and spinal cord

form the body's main

electrical hub.

The wiring they contain

is extremely delicate,

so they nestle inside the solid

bone layers

of the skull and vertebrae.

They're also suspended in a

clear fluid that absorbs shock.

No other piece of our biology

has this level of protection.

And for good reason.

Just like when the electrical

grids that power cities go dark,

a damaged nervous system

wreak havoc.

And for the body,

a blackout means pain.

-My name is Andy Haldane.

I'm a cell tower engineer.

The carrier reported

a signal loss,

so we're here today

to assess the situation

and make sure

we can bring the signal back up.

Ready to get this done?

- Let's do it.

-Today we're going to climb

a 120-foot tower.

Working on towers has

historically been

one of the most hazardous jobs

out there.

It's physically demanding.

Physically reaching and pulling

yourself up over and over again.

I don't care how in shape

you are,

you can only do

so many pull ups.

The longer I climb,

different fatigue

starts setting

in different places.

At some point you can't go on

without taking a breather.

- Hold, Mike.

- Yup.

- I do suffer from

lower back pain.

-Man, you gotta give me

a minute, Mike.

Needs a little aerial yoga,

getting this thing worked out.

-Tower climbing is not

for everybody.

I think it's a unique skill

set to be smart enough

to be an engineer and dumb

enough to climb a tower.

-One of the strongest lines

of evidence for evolution

is the fact

that we're not perfect.

When we look at our own bodies,

there are things

that don't make sense.

Like the fact that back pain

is so common in humans.

And that's because

our spinal column

is a structure that was based

on a quadrupedal design

because our ancestors

were quadrupeds and not bipeds.

So we've taken this quadrupedal

design and modified it

so that we can be upright,

which means

that our spine

have curvatures and shapes

that are not found

in other organisms.

-This design flaw means that

nerves often get sandwiched

between the very bones

meant to protect them

And when that happens, a whole

new neural sensation can occur:

pain.

In other words,

evolution kind of hurts.

-We have pain fibers

all throughout our body.

Now, these fibers can send

a specific signal

right to our brain, and our

brain can process this as pain.

And it also tells

what to do about it.

It then sends a signal back down

through a separate tract

on our spinal cord,

which then controls

the motor function

where the pain originated from.

This is why when you grab

a hot cup of water,

you immediately retract

your hand from it

without even thinking.

It's instantaneous.

- Pain is actually

a really good thing.

It's the nervous system's way

of telling you

that something is wrong,

so you can fix it.

But when that pain is caused

by a pinched nerve,

the effects can last much longer

because the thing that usually

tells us about damage

is itself in need of repair.

If you experience something

that feels like a burning,

stabbing, or sh**ting pain,

especially if there's numbness

or tingling,

it's likely to be a nerve pain.

And one of the most debilitating

forms of nerve pain

is sciatica.

-Hi, Andy, how are you doing?

Good to see you.

- Good to see you.

If you want to lay

on your left side,

facing me, we'll work

through your hips.

-Sciatica is a symptom

of compression

of one of the largest nerves

in the body.

The sciatic nerve starts

separate nerve roots

in the lower back.

They converge together

in the back of the hip

and then travel down the leg

as a single sciatic nerve

and then splits in the lower leg

and to separate nerves.

The majority of people have

inflammation around the discs

and their spine or herniation

or disc bulge

due to physical overuse.

It can happen at the hip

where the nerve comes out

of the pelvis into the leg.

It can basically happen anywhere

along the course of the nerve.

With Andy, with what he's doing

with climbing,

he's wearing harnesses,

his compression's

occurring actually

in the back of the hip

with some of those

muscles tightening

and sitting directly

on the nerve.

Nerves

don't like pressure on them

and they don't like

to be stretched,

so when you have

compression of the nerve

or if the nerves

are overstretched,

you're going to start to have

pain along the nerve

or you may present as numbness.

-Numbness is a clear sign

of system malfunction.

It means that neural connections

to the brain

have been compromised.

When a nerve is injured,

instead of going dark,

it starts firing even harder,

causing sensations

like pins and needles.

That's why when you hit

your elbow,

you feel a tingling

down your whole arm.

Your funny bone isn't a bone

at all.

It's a cluster of nerves.

Hit it just right, and you're

pinching those nerves,

sending confused signals

up and down your arm.

The same thing happens

when your foot falls asleep.

It's not really asleep,

and it has nothing to do

with blood flow.

It's a compressed nerve.

In both cases, the feeling

goes away after about a minute.

But the pain of sciatica

can last much longer.

Fortunately, the nervous system

is resilient,

and with proper treatment,

our bodies can bounce back.

-Okay. We'll do the same thing

on the other side.

I just want to keep you

balanced.

I know this leg doesn't have

too many issues.

-To treat sciatica,

I do a technique

called the active

release technique.

That's where I work the muscles

around the nerve

and try to get the nerve

to glide

better through those muscles.

We're just trying to free up

along the whole course

of the nerve so the nerve roots

come out here

and your lower back.

A lot of your restrictions

here behind your hip,

that's going to tighten up

a lot as you're climbing.

I think the workouts

have been helping you,

so I'd keep up with that.

-To help prevent future

sciatica pain,

Andy works on building strength

in his core and back.

Strong muscles

help stabilize the body.

And the act of building muscles

is in many ways

a neural activity.

-I'm big into physical fitness.

It helps me stay

in climbing shape.

You know, it's up to me to keep

myself in shape

mentally and physically in order

to maintain my ability

to do my job.

-You probably associate exercise

with your muscles or heart.

But recent studies have shown

that when we lift weights,

our nervous system actually

get stronger before our biceps.

Working out increases neurons

in certain parts of the brain.

That might be why when we train

to do a pull up,

we often achieve the feat

before we see any growth

in the muscles being used.

- Ready to finish this thing?

- Let's do it, man.

-Alright, let's rock and roll.

- I think it's

a personal challenge

to climb each structure.

It's something that's important

to me

to make sure the communications

system is intact

and able to function properly.

- Good here, here.

-There's definitely a feeling

of accomplishment

when you reach the top.

And the view is spectacular.

The stuff that I'm able to see

on a day-to-day basis

is pretty special.

I feel pretty lucky to be able

to do what I do for a living.

-The world around us

is always changing.

So as a species, we are

constantly finding ways

to react and adjust.

-The human body is such

an adaptable,

living system.

We often hear the adage

that our bodies

are like an exquisite machine.

It's interesting that throughout

so much of human history,

we tend to view our bodies

in a very similar way

to the dominant technology

of the day.

So around the same time that we

were learning

about interchangeable parts

on the assembly line

we started to view our bodies

in similar manners,

as a kind of accumulation

of parts.

But what I think is interesting

is that each of those parts

is comprised of many

other smaller functional units,

and that each of

those functional units

have their own intelligence.

-When I think about the

difference between humans

and other mammals,

I think about our brains.

Mentally we are extremely fit,

we have this incredible ability

to adapt to our circumstances

and persevere.

But what really grips me

is when I learn

about the ways

people are helping others.

The research scientists,

the biomedical engineers,

people out there who are making

these crazy advancements

in medical technology,

and somehow it always

comes back to neuroscience.

- Okay.

The next object is ready.

Ready?

- Ready.

-Try to tell us what it is.

- Okay.

-My name is Ranu Jung.

I'm a professor and chair

of the Department of Biomedical

Engineering

at Florida International

University.

My lab is called

the Adaptive Neural Systems lab,

and the idea is, can we do

something with engineering,

with technology, to restore

lost function inside the body?

How might we be able to restore

the sense of touch

to somebody that

has lost their hand?

-People are usually curious

about the cause.

How did you lose your arm?

What happened?

Sometimes

I'll say it was a gator.

Sometimes it was

a group of ninjas

'cause, you know, "car accident"

is a pretty boring story.

Losing an appendage, they say

it's like losing a loved one.

You go through mourning.

You really grieve the loss.

-I remember early on every day

was something

tying a trash bag, tying shoes.

He had a motorcycle at the time.

He no longer has a left hand

to pull in the clutch.

-If we brought an infant

into the world,

would I be able to care

for that infant?

Would I be able to to play

catch with my boy

in the front yard?

That really struck home to me,

and it really made me concerned

that this would be something

that would negatively affect me

for the rest of my life.

What would life be like

with just one hand?

-Our hands transmit a lot

of information to our brain

about the physical world.

So what happens when there's

an interruption

of all of that

input to the brain?

-You know how the first stage

of grief is denial.

That's kind of what happens

in the brain

when you lose a limb,

or so we think.

Our best guess is that

the information

traveling to the brain

comes to a screeching halt.

The brain thinks, "Well,

something must be really wrong.

The cells are dead,

but they can't be gone."

So it keeps trying to reach

a part of us

that's no longer there.

The strange phenomenon

of phantom pain.

And the brain

never really gives up.

The neurons that knew that hand

for your entire life

are kind of waiting

for a comeback.

-Shortly after the accident,

we were at the beach

and someone

threw a Frisbee at me

and I wasn't wearing

a prosthetic or anything.

I stuck my phantom limb

out to grab that Frisbee

and it went right by

and if my hand was there,

I would have caught it.

Even though it's not there,

my brain still thinks it is.

I feel tingling

and kind of numbness.

It never really goes away.

-We don't quite know why it is

that the mind

has a self-conception

of what signals are going

to be coming to it,

but what's really interesting

is that now

with certain bionic limbs,

we can create technology

that can speak

to the electrical signals

that are still being generated

in that healthy part

of the body.

-At Dr. Ranu Jung's lab

in Miami, Florida,

researchers

have created a neural interface

for Jason's prosthetic arm

that can tap into

the body's nervous system

and rekindle those

lost connections.

-When somebody loses an arm,

you can imagine that the nerves

that were communicating

back and forth are cut.

However, the rest of

the nerves are still intact.

So if there was a way

to communicate to those nerves,

then you could still perhaps

reach the spinal cord

or the brain.

That's what my lab is all about.

Can we make an advanced

prosthetic hand system

to restore the sense of touch?

-The first person in the world

to test this new,

experimental technology

is Jason Little.

- Hey, Jason, how are you doing?

- Good to see you.

- Good to see you.

How are things?

-Very good, very good.

-If you look at this

prosthetic arm,

he can open and close it.

But when a person opens

and closes a prosthetic hand,

they can't feel anything.

So if I were to put

my finger in there

and it could be squished hard,

but you know

this is a very special hand

because this has got sensors

in the prosthetic hand

and this sensor information

is being conveyed to Jason.

-The sensors in the hand

can actually send information

back to the brain

and how the brain interprets

that new sensation

is astonishing.

Something called

a neurostimulator

was implanted into Jason's arm.

Connected to this device

are fine wires like human hair,

which were threaded into

Jason's existing nerves

the ones that have been sitting

around in his upper arm

waiting for a signal.

-Right here inside Jason's arm

is a little radio receiver,

and there's a little magnet

in that

and this has a little magnet.

And so if you put it here,

see it links together.

So the information from the

outside goes to the fine wires

into the nerves

that are inside the arm.

These are the same nerves

that are there in all of us

that take information

from the hands

and then go into the brain.

- An unbroken line

of communication

from Jason's prosthetic

fingertips

all the way up

to his very human brain

But will Jason's brain accept,

and even more importantly,

understand, this new signal?

- Hey, Jason.

- Hey, how's it going, Andres?

- How are you?

- Good.

-Alright, let me have your hand.

-Jason is the first person

to have this implant system.

- Ready to play with some blocks?

- Yeah, let's do it.

-And is providing us

with very needed data

to tell us how safe,

how efficacious is the system.

- So in this test,

what we want to know

is what is Jason's capability to

figure out the sense of touch.

So we want to isolate him

from anything

that may give him a clue.

We have separated out

the prosthetic arm

so he cannot feel

the vibrations of the motors

so that he can purely rely on

the sensation that he's getting.

-We're going to try to see

if you can detect the difference

between a hard block

or a soft block,

that they should deliver

sensation that you will get.

And just tell me

what you think the block is.

Let's start by taking

the stimulation off.

So will you remove your coil

please?

Okay.

-By removing the transmitter,

Jason's preventing

any information

coming from his hand

from reaching his brain.

-The block is ready.

-I have no stimulation

to give me feedback.

So this is completely a guess

in the dark to say

that this is a soft object.

-So that was incorrect.

-Next, Jason connects

the transmitter to his arm,

creating a continuous

neural path from hand

to brain.

-I'll turn it on for you.

Let me know

if you start feeling it.

Ah!

-He's giving you a heart attack.

- Could you open

and close the hand?

Good to go?

- Yep.

Are you getting stimulation,

getting sensation?

- Yes.

- Perfect.

Jason, next block is ready,

you can close the hand.

-Um, I feel this sensation

come on very slowly

rather than abruptly.

So this block is soft,

and it's large soft.

-You are 100% correct.

-I can actually feel

a little vibrating tingling

sensation

in my phantom limb

telling me that I am making

contact with an object.

-How is the brain adapting?

Will this process

of neurostimulation

over weeks, months, years

actually change

the organization in the brain?

-Putting my arm on,

it immediately becomes

part of me.

It's no longer

this foreign object.

It's It's my left arm.

-For years, Jason's brain

was left wondering

what happened to his hand,

still trying to speak to it,

trying to reach it.

Then one day, strange new

messages started coming back.

They weren't like the old ones,

but they're familiar enough,

speaking a language

the brain could understand.

This technology gives the brain

the chance

to do what it's best at

adapt.

-Our brains are very plastic,

so they're always changing.

The adult brain has much more

capacity for hacking itself

Being able to rewire in ways

that we didn't

anticipate before.

-You know, having that touch

sensation come back

was something that I never

thought I would have.

That confidence that

I've gained now

has been a game changer for me.

It's allowed me to regain

a little bit

of my old self back again.

Since I get sensory feedback,

I know how hard I'm holding

this egg,

so, um, I know

that if I push down any further,

I'm going to

completely crush it.

The first time I felt

the sensation,

we had Krystal

put her hand in mine.

I closed my eyes and I slowly

closed the hand down

on her hand, and I let her know

that I was able

to feel her holding my hand.

- Just Just,

it was a realization

that this is as much as this

is research to other people,

this is our real lives.

-The longer this has gone on,

the more I realized,

this has nothing to do with me.

This is all about the people

that this is going to impact

years from now,

decades from now.

It's really given me a sense

of purpose

that losing my arm

wasn't in vain.

-Today it is for communicating

with the prosthetic hand.

Tomorrow it could be for people

who've lost both hands,

they've lost a foot.

Down the road by stimulating

the nerves

that control the spleen,

that control the stomach,

that impact your immune system,

we make cure a disease one day.

-It's astonishing to me just

how adaptable

our living systems are

to environments

that are so diverse.

-The brain is evolving,

that's for sure.

We know it because

our nervous system

allows us to interact

with the environment.

So as long as the environment

changes,

also the brain

will keep changing.

-By managing everything

that's going on inside the body

and keeping us in touch

with what's outside,

the nervous system

is at the core of who we are.

-What makes me realize

that we have a lot more to learn

about human potential

is what human beings

are able to adapt to.

The crazy ways people

are breaking world records,

simply by learning to be more

efficient and trying harder.

The ways people are surviving

these horrific events,

the way people are able to

translate a terrible experience

into a phenomenal story.

A lot of it has to do with

the way we take information in

and we process it out

in our own artistic way.