Miguel Nicolelis: A monkey that controls a robot with its thoughts. No, really.

247,355 views ・ 2013-02-18

TED


Please double-click on the English subtitles below to play the video.

00:00
Translator: Timothy Covell Reviewer: Morton Bast
0
0
7000
00:15
The kind of neuroscience that I do and my colleagues do
1
15660
2851
00:18
is almost like the weatherman.
2
18511
2166
00:20
We are always chasing storms.
3
20677
3516
00:24
We want to see and measure storms -- brainstorms, that is.
4
24193
4883
00:29
And we all talk about brainstorms in our daily lives,
5
29076
2768
00:31
but we rarely see or listen to one.
6
31844
3450
00:35
So I always like to start these talks
7
35294
1634
00:36
by actually introducing you to one of them.
8
36928
2982
00:39
Actually, the first time we recorded more than one neuron --
9
39910
3427
00:43
a hundred brain cells simultaneously --
10
43337
2223
00:45
we could measure the electrical sparks
11
45560
2469
00:48
of a hundred cells in the same animal,
12
48029
2680
00:50
this is the first image we got,
13
50709
1802
00:52
the first 10 seconds of this recording.
14
52511
2315
00:54
So we got a little snippet of a thought,
15
54826
3351
00:58
and we could see it in front of us.
16
58177
2905
01:01
I always tell the students
17
61082
1012
01:02
that we could also call neuroscientists some sort of astronomer,
18
62094
4106
01:06
because we are dealing with a system
19
66200
1626
01:07
that is only comparable in terms of number of cells
20
67826
2917
01:10
to the number of galaxies that we have in the universe.
21
70743
2936
01:13
And here we are, out of billions of neurons,
22
73679
3030
01:16
just recording, 10 years ago, a hundred.
23
76709
2818
01:19
We are doing a thousand now.
24
79527
1583
01:21
And we hope to understand something fundamental about our human nature.
25
81110
5400
01:26
Because, if you don't know yet,
26
86510
1932
01:28
everything that we use to define what human nature is comes from these storms,
27
88442
5250
01:33
comes from these storms that roll over the hills and valleys of our brains
28
93692
4651
01:38
and define our memories, our beliefs,
29
98343
3885
01:42
our feelings, our plans for the future.
30
102228
2700
01:44
Everything that we ever do,
31
104928
2398
01:47
everything that every human has ever done, do or will do,
32
107326
5067
01:52
requires the toil of populations of neurons producing these kinds of storms.
33
112393
5434
01:57
And the sound of a brainstorm, if you've never heard one,
34
117827
2483
02:00
is somewhat like this.
35
120310
3349
02:03
You can put it louder if you can.
36
123659
3146
02:06
My son calls this "making popcorn while listening to a badly-tuned A.M. station."
37
126805
6403
02:13
This is a brain.
38
133208
1485
02:14
This is what happens when you route these electrical storms to a loudspeaker
39
134693
3434
02:18
and you listen to a hundred brain cells firing,
40
138127
2866
02:20
your brain will sound like this -- my brain, any brain.
41
140993
4622
02:25
And what we want to do as neuroscientists in this time
42
145615
3762
02:29
is to actually listen to these symphonies, these brain symphonies,
43
149377
5350
02:34
and try to extract from them the messages they carry.
44
154727
3400
02:38
In particular, about 12 years ago
45
158127
2851
02:40
we created a preparation that we named brain-machine interfaces.
46
160978
3048
02:44
And you have a scheme here that describes how it works.
47
164026
2702
02:46
The idea is, let's have some sensors that listen to these storms, this electrical firing,
48
166728
5566
02:52
and see if you can, in the same time that it takes
49
172294
3082
02:55
for this storm to leave the brain and reach the legs or the arms of an animal --
50
175376
4969
03:00
about half a second --
51
180345
2864
03:03
let's see if we can read these signals,
52
183209
2351
03:05
extract the motor messages that are embedded in it,
53
185560
3400
03:08
translate it into digital commands
54
188960
2272
03:11
and send it to an artificial device
55
191232
1886
03:13
that will reproduce the voluntary motor wheel of that brain in real time.
56
193118
5893
03:19
And see if we can measure how well we can translate that message
57
199011
3848
03:22
when we compare to the way the body does that.
58
202859
3518
03:26
And if we can actually provide feedback,
59
206377
2866
03:29
sensory signals that go back from this robotic, mechanical, computational actuator
60
209243
5734
03:34
that is now under the control of the brain,
61
214977
2251
03:37
back to the brain,
62
217228
1311
03:38
how the brain deals with that,
63
218539
2121
03:40
of receiving messages from an artificial piece of machinery.
64
220660
4901
03:45
And that's exactly what we did 10 years ago.
65
225561
2321
03:47
We started with a superstar monkey called Aurora
66
227882
2961
03:50
that became one of the superstars of this field.
67
230843
2468
03:53
And Aurora liked to play video games.
68
233311
2299
03:55
As you can see here,
69
235610
1373
03:56
she likes to use a joystick, like any one of us, any of our kids, to play this game.
70
236983
4944
04:01
And as a good primate, she even tries to cheat before she gets the right answer.
71
241927
4671
04:06
So even before a target appears that she's supposed to cross
72
246598
4283
04:10
with the cursor that she's controlling with this joystick,
73
250881
2850
04:13
Aurora is trying to find the target, no matter where it is.
74
253731
3951
04:17
And if she's doing that,
75
257682
1469
04:19
because every time she crosses that target with the little cursor,
76
259151
3314
04:22
she gets a drop of Brazilian orange juice.
77
262465
2950
04:25
And I can tell you, any monkey will do anything for you
78
265415
2950
04:28
if you get a little drop of Brazilian orange juice.
79
268365
3100
04:31
Actually any primate will do that.
80
271465
2731
04:34
Think about that.
81
274196
1334
04:35
Well, while Aurora was playing this game, as you saw,
82
275530
3400
04:38
and doing a thousand trials a day
83
278930
2435
04:41
and getting 97 percent correct and 350 milliliters of orange juice,
84
281365
3883
04:45
we are recording the brainstorms that are produced in her head
85
285248
3399
04:48
and sending them to a robotic arm
86
288647
1647
04:50
that was learning to reproduce the movements that Aurora was making.
87
290294
3871
04:54
Because the idea was to actually turn on this brain-machine interface
88
294165
3783
04:57
and have Aurora play the game just by thinking,
89
297948
4700
05:02
without interference of her body.
90
302648
2617
05:05
Her brainstorms would control an arm
91
305265
2916
05:08
that would move the cursor and cross the target.
92
308181
2709
05:10
And to our shock, that's exactly what Aurora did.
93
310890
3191
05:14
She played the game without moving her body.
94
314081
4200
05:18
So every trajectory that you see of the cursor now,
95
318281
2237
05:20
this is the exact first moment she got that.
96
320518
3212
05:23
That's the exact first moment
97
323730
1784
05:25
a brain intention was liberated from the physical domains of a body of a primate
98
325514
6767
05:32
and could act outside, in that outside world,
99
332281
3700
05:35
just by controlling an artificial device.
100
335981
2966
05:38
And Aurora kept playing the game, kept finding the little target
101
338947
4917
05:43
and getting the orange juice that she wanted to get, that she craved for.
102
343864
3917
05:47
Well, she did that because she, at that time, had acquired a new arm.
103
347781
6701
05:54
The robotic arm that you see moving here 30 days later,
104
354482
2963
05:57
after the first video that I showed to you,
105
357445
2686
06:00
is under the control of Aurora's brain
106
360131
2650
06:02
and is moving the cursor to get to the target.
107
362781
3168
06:05
And Aurora now knows that she can play the game with this robotic arm,
108
365949
3899
06:09
but she has not lost the ability to use her biological arms to do what she pleases.
109
369848
5716
06:15
She can scratch her back, she can scratch one of us, she can play another game.
110
375564
4067
06:19
By all purposes and means,
111
379631
1600
06:21
Aurora's brain has incorporated that artificial device
112
381231
4116
06:25
as an extension of her body.
113
385347
2750
06:28
The model of the self that Aurora had in her mind
114
388097
3533
06:31
has been expanded to get one more arm.
115
391630
4084
06:35
Well, we did that 10 years ago.
116
395714
2350
06:38
Just fast forward 10 years.
117
398064
2833
06:40
Just last year we realized that you don't even need to have a robotic device.
118
400897
4983
06:45
You can just build a computational body, an avatar, a monkey avatar.
119
405880
5484
06:51
And you can actually use it for our monkeys to either interact with them,
120
411364
4250
06:55
or you can train them to assume in a virtual world
121
415614
4439
07:00
the first-person perspective of that avatar
122
420053
3044
07:03
and use her brain activity to control the movements of the avatar's arms or legs.
123
423097
5651
07:08
And what we did basically was to train the animals
124
428748
2766
07:11
to learn how to control these avatars
125
431514
3050
07:14
and explore objects that appear in the virtual world.
126
434564
3899
07:18
And these objects are visually identical,
127
438463
2301
07:20
but when the avatar crosses the surface of these objects,
128
440764
3883
07:24
they send an electrical message that is proportional to the microtactile texture of the object
129
444647
6400
07:31
that goes back directly to the monkey's brain,
130
451047
4016
07:35
informing the brain what it is the avatar is touching.
131
455063
5052
07:40
And in just four weeks, the brain learns to process this new sensation
132
460115
4765
07:44
and acquires a new sensory pathway -- like a new sense.
133
464880
6434
07:51
And you truly liberate the brain now
134
471314
2416
07:53
because you are allowing the brain to send motor commands to move this avatar.
135
473730
4384
07:58
And the feedback that comes from the avatar is being processed directly by the brain
136
478114
5000
08:03
without the interference of the skin.
137
483114
2433
08:05
So what you see here is this is the design of the task.
138
485547
2534
08:08
You're going to see an animal basically touching these three targets.
139
488081
4250
08:12
And he has to select one because only one carries the reward,
140
492331
4349
08:16
the orange juice that they want to get.
141
496680
1867
08:18
And he has to select it by touch using a virtual arm, an arm that doesn't exist.
142
498547
5633
08:24
And that's exactly what they do.
143
504180
2000
08:26
This is a complete liberation of the brain
144
506180
3435
08:29
from the physical constraints of the body and the motor in a perceptual task.
145
509615
4282
08:33
The animal is controlling the avatar to touch the targets.
146
513897
4167
08:38
And he's sensing the texture by receiving an electrical message directly in the brain.
147
518064
5651
08:43
And the brain is deciding what is the texture associated with the reward.
148
523715
3883
08:47
The legends that you see in the movie don't appear for the monkey.
149
527598
3832
08:51
And by the way, they don't read English anyway,
150
531430
2484
08:53
so they are here just for you to know that the correct target is shifting position.
151
533914
5216
08:59
And yet, they can find them by tactile discrimination,
152
539130
3934
09:03
and they can press it and select it.
153
543064
3217
09:06
So when we look at the brains of these animals,
154
546281
2682
09:08
on the top panel you see the alignment of 125 cells
155
548963
3667
09:12
showing what happens with the brain activity, the electrical storms,
156
552630
4201
09:16
of this sample of neurons in the brain
157
556831
2067
09:18
when the animal is using a joystick.
158
558898
2116
09:21
And that's a picture that every neurophysiologist knows.
159
561014
2600
09:23
The basic alignment shows that these cells are coding for all possible directions.
160
563614
5183
09:28
The bottom picture is what happens when the body stops moving
161
568797
5683
09:34
and the animal starts controlling either a robotic device or a computational avatar.
162
574480
6134
09:40
As fast as we can reset our computers,
163
580614
3066
09:43
the brain activity shifts to start representing this new tool,
164
583680
5818
09:49
as if this too was a part of that primate's body.
165
589498
5250
09:54
The brain is assimilating that too, as fast as we can measure.
166
594748
4715
09:59
So that suggests to us that our sense of self
167
599463
3618
10:03
does not end at the last layer of the epithelium of our bodies,
168
603081
4150
10:07
but it ends at the last layer of electrons of the tools that we're commanding with our brains.
169
607231
5718
10:12
Our violins, our cars, our bicycles, our soccer balls, our clothing --
170
612949
4764
10:17
they all become assimilated by this voracious, amazing, dynamic system called the brain.
171
617713
6851
10:24
How far can we take it?
172
624564
1699
10:26
Well, in an experiment that we ran a few years ago, we took this to the limit.
173
626263
4218
10:30
We had an animal running on a treadmill
174
630481
2482
10:32
at Duke University on the East Coast of the United States,
175
632963
2267
10:35
producing the brainstorms necessary to move.
176
635230
2700
10:37
And we had a robotic device, a humanoid robot,
177
637930
4091
10:42
in Kyoto, Japan at ATR Laboratories
178
642021
2394
10:44
that was dreaming its entire life to be controlled by a brain,
179
644415
6094
10:50
a human brain, or a primate brain.
180
650509
3273
10:53
What happens here is that the brain activity that generated the movements in the monkey
181
653782
4598
10:58
was transmitted to Japan and made this robot walk
182
658380
3467
11:01
while footage of this walking was sent back to Duke,
183
661847
4067
11:05
so that the monkey could see the legs of this robot walking in front of her.
184
665914
5233
11:11
So she could be rewarded, not by what her body was doing
185
671147
4067
11:15
but for every correct step of the robot on the other side of the planet
186
675214
4961
11:20
controlled by her brain activity.
187
680175
2609
11:22
Funny thing, that round trip around the globe took 20 milliseconds less
188
682784
7118
11:29
than it takes for that brainstorm to leave its head, the head of the monkey,
189
689902
4150
11:34
and reach its own muscle.
190
694052
3870
11:37
The monkey was moving a robot that was six times bigger, across the planet.
191
697922
6030
11:43
This is one of the experiments in which that robot was able to walk autonomously.
192
703952
6400
11:50
This is CB1 fulfilling its dream in Japan
193
710352
5267
11:55
under the control of the brain activity of a primate.
194
715619
3700
11:59
So where are we taking all this?
195
719319
1989
12:01
What are we going to do with all this research,
196
721308
2343
12:03
besides studying the properties of this dynamic universe that we have between our ears?
197
723651
5668
12:09
Well the idea is to take all this knowledge and technology
198
729319
4833
12:14
and try to restore one of the most severe neurological problems that we have in the world.
199
734152
5484
12:19
Millions of people have lost the ability to translate these brainstorms
200
739636
4583
12:24
into action, into movement.
201
744219
2116
12:26
Although their brains continue to produce those storms and code for movements,
202
746335
5234
12:31
they cannot cross a barrier that was created by a lesion on the spinal cord.
203
751569
5167
12:36
So our idea is to create a bypass,
204
756736
2450
12:39
is to use these brain-machine interfaces to read these signals,
205
759186
4032
12:43
larger-scale brainstorms that contain the desire to move again,
206
763218
4050
12:47
bypass the lesion using computational microengineering
207
767268
3969
12:51
and send it to a new body, a whole body called an exoskeleton,
208
771237
7114
12:58
a whole robotic suit that will become the new body of these patients.
209
778351
5567
13:03
And you can see an image produced by this consortium.
210
783918
4126
13:08
This is a nonprofit consortium called the Walk Again Project
211
788044
4059
13:12
that is putting together scientists from Europe,
212
792103
2783
13:14
from here in the United States, and in Brazil
213
794886
1865
13:16
together to work to actually get this new body built --
214
796751
4517
13:21
a body that we believe, through the same plastic mechanisms
215
801268
3334
13:24
that allow Aurora and other monkeys to use these tools through a brain-machine interface
216
804602
5802
13:30
and that allows us to incorporate the tools that we produce and use in our daily life.
217
810404
5630
13:36
This same mechanism, we hope, will allow these patients,
218
816034
3684
13:39
not only to imagine again the movements that they want to make
219
819718
3768
13:43
and translate them into movements of this new body,
220
823486
3207
13:46
but for this body to be assimilated as the new body that the brain controls.
221
826693
6758
13:53
So I was told about 10 years ago
222
833451
3851
13:57
that this would never happen, that this was close to impossible.
223
837302
5066
14:02
And I can only tell you that as a scientist,
224
842368
2451
14:04
I grew up in southern Brazil in the mid-'60s
225
844819
2986
14:07
watching a few crazy guys telling [us] that they would go to the Moon.
226
847805
5048
14:12
And I was five years old,
227
852853
1461
14:14
and I never understood why NASA didn't hire Captain Kirk and Spock to do the job;
228
854314
4240
14:18
after all, they were very proficient --
229
858554
2432
14:20
but just seeing that as a kid
230
860986
3450
14:24
made me believe, as my grandmother used to tell me,
231
864436
2985
14:27
that "impossible is just the possible
232
867421
1845
14:29
that someone has not put in enough effort to make it come true."
233
869266
3904
14:33
So they told me that it's impossible to make someone walk.
234
873170
3799
14:36
I think I'm going to follow my grandmother's advice.
235
876969
3251
14:40
Thank you.
236
880220
1450
14:41
(Applause)
237
881670
8029
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7