How to control someone else's arm with your brain

The brain is an amazing and complex organ.

And while many people are fascinated
by the brain,

that can't really tell you that much
about the properties

about how the brain works

because we don't teach
neuroscience in schools.

And one of the reasons why is that
the equipment

is so complex and so expensive

that it's really only done
at major universities

and large institutions.

And so in order to be able
to access the brain,

you really need to dedicate your life
as spend six and a half years

as a graduate student just
to become a neuroscientist

who gets access to these tools.

And that's a shame because
one out of five of us,

that's 20 percent of the entire world,

will have a neurological disorder.

And there are zero cures
for these diseases.

And so it seems that what
we should be doing

is reaching back earlier
in the eduction process

and teaching students
about neuroscience

so that in the future, they may be
thinking about

possibly becoming a brain scientist.

When I was a graduate student,
my lab mate Tim Marzullo and myself,

decided that what if we took this
complex equipment that we have

for studying the brain
and made it simple enough

and affordable enough that
anyone that you know,

an ameatur or a high school student,

could learn and actually
learn and participate

in the discovery of neuroscience.

And so we did just that.

A few years ago, we started
a company called Backyard Brains

and we make DIY neuroscience equipment

and I brought some here tonight

and I want to do some demonstrations,

you guys want to see some?

So I need a volunteer.

What is your name?

All right, Sam, I'm going
to record from your brain,

have you had this before?

Sam: No.

Greg Gage: I need you to stick out
your arm for science,

roll up your sleeve a bit,

So what I'm going to do,

I'm putting electrodes on your arm,

and you're probably wondering

I just said I'm going to record
from your brain,

what am I doing with my arm?

Well you have about
80 billion neurons

inside your brain right now,

they're sending electrical messages
back and forth and chemical messages.

Some of your neurons right here
in your motor cortex

are going to send messages down
when you move your arm like this.

They're going to go down
across your corpus callosum,

down onto your spinal cord
to your lower motor neuron

out to your muscles here,

and that electrical discharge
is going to be picked up

by these electrodes right here

and we're going to listen to exactly
what your brain is going to be doing.

So I'm going to turn this on for a second,

have you ever heard
what your brain sounds like?

Sam: No.

GG: All right, let's try it out.

So go ahead and squeeze your hand.

[ sound of neurons]

So what you're listening to,

so this is your motor units
happening right here.

Let's take a look at it as well.

So I'm going to stand over here,

and I'm going to open up our app here.

So now I want you to squeeze.

[neurons]

So right here, these are
the motor units

that are happening from her spinal cord,

out to her muscle right here,

and as she's doing it, you're seeing
the electrical activity

that's happening here.

You can even click here
and try to see one of them.

So keep doing it really, really hard.

So now we've paused,

and one motor action potential
that's happening right now

inside of your brain.

Do you guys want to see some more?

(Applause)

That's interesting,
but let's get it better.

I need one more volunteer.

What is your name sir?

Man: Miguel.

GG: Miguel?

You're going to stand right here.

So when you're moving your arm like this,

your brain is sending a signal
down to your muscle right here.

I want you to move your arm as well.

So your brain is going to send
a signal down to your muscle.

And so it turns out that there is
a nerve that's right here

that runs up here that enervates
these three fingers

and it's close enough to the skin
that we might be able

to stimulate that so that
what we can do

is copy your brain signals
going out to your hand

and inject it into your hand,

so that your hand will move

when your brain tells your hand to move.

So in a sense, she will take away
your free will

and you will no longer have
any control over this hand.

You with me?

So I just need to hook you up.

So I'm going to find your ulnar nerve,

which is probably right around here.

You don't know what
you're signing up for

when you come up.

So now I'm going to move away
and we're going to plug it

into our human-to-human interface
over here.

Okay, so Sam, I want you
to squeeze your hand again.

Do it again, perfect.

So now I'm going to hook you up
over here so that you get the --

it's going to feel a little weird
at first, this is going to feel like a...

(Laughter)

you know, when you loose your free will,

and someone else becomes your agent,

it does feel a bit strange.

Now I want you to relax your hand.

Alright, Sam, you're with me?

So you're going to squeeze it,

I'm not going to turn it on you.

So go ahead and give it a squeeze.

So now, are you ready, Miguel?

Miguel: I'm as ready as I'll ever be.

GG: I've turned it on, so go ahead
and turn your hand.

Do you feel that a little bit,

you want to do it again?

A little bit?

So relax.

So hit it again.

(Laughter)

Oh, perfect, perfect.

So relax, do it again.

All right, so right now,

your brain is controlling your arm

and it's also controlling his arm,

so go ahead and just do it
one more time.

(Laughter)

All right, so it's perfect.

So now, what would happen
if I took over my control

of your hand?

And so, just relax your hand.

What happens?

Ah, nothing.

Why not?

Because the brain has to do it.

So you do it again.

All right, it's perfect.

All right, thank you guys
for being such a good sport,

this is what's happening
all across the world, electrophysiology,

we're going to bring on the neuro-revolution.

Thank you.

(Applause)