How to control someone else's arm with your brain | Greg Gage

The brain is an amazing and complex organ.

And while many peopleare fascinated by the brain, they can't really tell you that much about the propertiesabout how the brain works because we don't teachneuroscience in schools.

And one of the reasonswhy is that the equipment is so complex and so expensive that it's really only done at majoruniversities and large institutions.

And so in order to be ableto access the brain, you really need to dedicate your life and spend six and a half yearsas a graduate student just to become a neuroscientistto get access to these tools.

And that's a shamebecause one out of five of us, that's 20 percent of the entire world, will have a neurological disorder.

And there are zero curesfor these diseases.

And so it seems thatwhat we should be doing is reaching back earlierin the eduction process and teaching students about neuroscienceso that in the future, they may be thinking about possiblybecoming a brain scientist.

When I was a graduate student, my lab mate Tim Marzullo and myself, decided that what if we tookthis complex equipment that we have for studying the brain and made it simpleenough and affordable enough that anyone that you know, an amateuror a high school student, could learn and actually participatein the discovery of neuroscience.

And so we did just that.

A few years ago, we starteda company called Backyard Brains and we make DIY neuroscience equipmentand I brought some here tonight, and I want to do some demonstrations.

You guys want to see some? So I need a volunteer.

So right before — what is your name?(Applause) Sam Kelly: Sam.

Greg Gage: All right, Sam, I'm goingto record from your brain.

Have you had this before? SK: No.

GG: I need you to stick outyour 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 yourbrain, what am I doing with your arm? Well, you have about 80 billion neuronsinside your brain right now.

They're sending electrical messagesback and forth, and chemical messages.

But some of your neuronsright here in your motor cortex are going to send messages downwhen you move your arm like this.

They're going to go downacross your corpus callosum, down onto your spinal cordto your lower motor neuron out to your muscles here, and that electrical dischargeis going to be picked up by these electrodes right here and we're going to be able to listen to exactly what your brainis going to be doing.

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

Have you ever heardwhat your brain sounds like? SK: No.

GG: Let's try it out.

So go ahead and squeeze your hand.

(Rumbling) So what you're listening to, so this is your motor unitshappening 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.

(Rumbling) So right here, these are the motor unitsthat are happening from her spinal cordout to her muscle right here, and as she's doing it, you're seeing the electrical activitythat's happening here.

You can even click hereand try to see one of them.

So keep doing it really hard.

So now we've paused on one motor action potential that'shappening 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? Miguel Goncalves: Miguel.

GG: Miguel, all right.

You're going to stand right here.

So when you're moving your arm like this, your brain is sending a signaldown to your muscles right here.

I want you to move your arm as well.

So your brain is going to senda signal down to your muscles.

And so it turns out that there isa nerve that's right here that runs up here that innervatesthese three fingers, and it's close enough to the skinthat we might be able to stimulate that so that what we can do is copy your brain signalsgoing out to your hand and inject it into your hand, so that your hand will movewhen your brain tells your hand to move.

So in a sense, she will take awayyour free will and you will no longer haveany control over this hand.

You with me? So I just need to hook you up.

(Laughter) 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 awayand we're going to plug it in to our human-to-human interface over here.

Okay, so Sam, I want youto squeeze your hand again.

Do it again.

Perfect.

So now I'm going to hook you upover here so that you get the — It's going to feela little bit weird at first, this is going to feel like a –(Laughter) You know, when you lose your free will, and someone else becomes your agent, it does feel a bit strange.

Now I want you to relax your hand.

Sam, you're with me? So you're going to squeeze.

I'm not going to turn it on yet, so go ahead and give it a squeeze.

So now, are you ready, Miguel? MG: Ready as I'll ever be.

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

Do you feel that a little bit?MG: Nope.

GG: Okay, do it again?MG: A little bit.

GG: A little bit? (Laughter) 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 armand it's also controlling his arm, so go ahead and just do it one more time.

All right, so it's perfect.

(Laughter) So now, what would happenif 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, that's perfect.

Thank you guys for beingsuch a good sport.

This is what's happeningall across the world — electrophysiology! We're going to bring onthe neuro-revolution.

Thank you.

(Applause).