How we can use light to see deep inside our bodies and brains | Mary Lou Jepsen

293,820 views ・ 2018-08-24

TED


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

00:12
People don't realize
0
12722
1887
00:14
that red light and benign near-infrared light
1
14633
4159
00:18
go right through your hand, just like this.
2
18816
3357
00:23
This fact could enable better, faster and cheaper health care.
3
23157
5186
00:28
Our translucence is key here.
4
28696
2905
00:32
I'm going to show you how we use this key and a couple of other keys
5
32093
3862
00:35
to see deep inside our bodies and brains.
6
35979
2733
00:40
OK, so first up ...
7
40043
1515
00:42
You see this laser pointer and the spot it makes on my hand?
8
42868
3431
00:47
The light goes right through my hand --
9
47624
1886
00:49
if we could bring the lights down, please --
10
49534
2067
00:51
as I've already shown.
11
51625
1181
00:52
But you can no longer see that laser spot.
12
52830
2754
00:55
You see my hand glow.
13
55608
1460
00:58
That's because the light spreads out, it scatters.
14
58013
3690
01:02
I need you to understand what scattering is,
15
62226
3208
01:05
so I can show you how we get rid of it
16
65458
2802
01:08
and see deep inside our bodies and brains.
17
68284
2436
01:12
So, I've got a piece of chicken back here.
18
72419
2491
01:15
(Laughter)
19
75683
1386
01:17
It's raw.
20
77093
1150
01:20
Putting on some gloves.
21
80085
1618
01:21
It's got the same optical properties as human flesh.
22
81727
4543
01:29
So, here's the chicken ... putting it on the light.
23
89204
4531
01:34
Can you see, the light goes right through?
24
94744
2156
01:38
I also implanted a tumor in that chicken.
25
98731
2733
01:42
Can you see it?
26
102215
1180
01:43
Audience: Yes.
27
103419
1328
01:44
Mary Lou Jepsen: So this means, using red light and infrared light,
28
104771
4672
01:49
we can see tumors in human flesh.
29
109467
2457
01:53
But there's a catch.
30
113117
1333
01:55
When I throw another piece of chicken on it,
31
115534
2294
01:59
the light still goes through,
32
119137
1787
02:02
but you can no longer see the tumor.
33
122050
2400
02:05
That's because the light scatters.
34
125188
2619
02:08
So we have to do something about the scatter
35
128633
2284
02:10
so we can see the tumor.
36
130941
1600
02:14
We have to de-scatter the light.
37
134055
2133
02:17
So ...
38
137245
1150
02:19
A technology I spent the early part of my career on
39
139785
2848
02:22
enables de-scattering.
40
142657
1468
02:24
It's called holography.
41
144720
1533
02:26
And it won the Nobel Prize in physics in the 70s,
42
146728
2936
02:29
because of the fantastic things it enables you to do with light.
43
149688
4032
02:34
This is a hologram.
44
154879
1267
02:36
It captures all of the light, all of the rays, all of the photons
45
156934
4571
02:41
at all of the positions and all of the angles, simultaneously.
46
161529
4510
02:47
It's amazing.
47
167173
1150
02:48
To see what we can do with holography ...
48
168831
2631
02:53
You see these marbles?
49
173022
1476
02:54
Look at these marbles bouncing off of the barriers,
50
174522
2709
02:57
as an analogy to light being scattered by our bodies.
51
177688
3730
03:02
As the marbles get to the bottom of the scattering maze,
52
182323
4016
03:06
they're chaotic, they're scattering and bouncing everywhere.
53
186363
4067
03:11
If we record a hologram at the bottom inside of the screen,
54
191046
4206
03:15
we can record the position and angle of each marble exiting the maze.
55
195276
6539
03:22
And then we can bring in marbles from below
56
202339
2514
03:26
and have the hologram direct each marble to exactly the right position and angle,
57
206061
6148
03:32
such as they emerge in a line at the top of the scatter matrix.
58
212233
5262
03:39
We're going to do that with this.
59
219162
1916
03:41
This is optically similar to human brain.
60
221732
4282
03:46
I'm going to switch to green light now,
61
226787
2690
03:49
because green light is brighter to your eyes than red or infrared,
62
229501
3758
03:53
and I really need you to see this.
63
233283
1960
03:55
So we're going to put a hologram in front of this brain
64
235665
4825
04:00
and make a stream of light come out of it.
65
240514
2666
04:04
Seems impossible but it isn't.
66
244831
2929
04:07
This is the setup you're going to see.
67
247784
2206
04:10
Green light.
68
250014
1150
04:12
Hologram here, green light going in,
69
252514
2865
04:15
that's our brain.
70
255403
1150
04:18
And a stream of light comes out of it.
71
258458
4391
04:22
We just made a brain lase of densely scattering tissue.
72
262873
4730
04:27
Seems impossible, no one's done this before,
73
267627
3270
04:30
you're the first public audience to ever see this.
74
270921
2740
04:33
(Applause)
75
273685
4786
04:38
What this means is that we can focus deep into tissue.
76
278495
3667
04:42
Our translucency is the first key.
77
282805
3010
04:45
Holography enabling de-scattering is the second key
78
285839
4031
04:49
to enable us to see deep inside of our bodies and brains.
79
289894
3867
04:54
You're probably thinking,
80
294981
1667
04:57
"Sounds good, but what about skull and bones?
81
297118
3009
05:00
How are you going to see through the brain without seeing through bone?"
82
300151
4070
05:04
Well, this is real human skull.
83
304245
2288
05:07
We ordered it at skullsunlimited.com.
84
307188
3135
05:10
(Laughter)
85
310347
1746
05:12
No kidding.
86
312117
1238
05:13
But we treat this skull with great respect at our lab and here at TED.
87
313379
4724
05:18
And as you can see,
88
318127
1596
05:20
the red light goes right through it.
89
320770
1990
05:23
Goes through our bones.
90
323912
1535
05:25
So we can go through skull and bones and flesh with just red light.
91
325471
5018
05:31
Gamma rays and X-rays do that, too, but they cause tumors.
92
331268
3729
05:35
Red light is all around us.
93
335637
3076
05:39
So, using that, I'm going to come back here
94
339137
2904
05:42
and show you something more useful than making a brain lase.
95
342065
3403
05:46
We challenged ourselves to see how fine we could focus through brain tissue.
96
346229
3954
05:50
Focusing through this brain,
97
350967
2102
05:53
it was such a fine focus, we put a bare camera die in front of it.
98
353093
4574
05:58
And the bare camera die ...
99
358288
1800
06:03
Could you turn down the spotlight?
100
363454
1627
06:05
OK, there it is.
101
365105
1150
06:07
Do you see that?
102
367117
1159
06:08
Each pixel is two-thousandths of a millimeter wide.
103
368300
4276
06:13
Two microns.
104
373673
1404
06:15
That means that spot focus -- full width half max --
105
375101
3389
06:18
is six to eight microns.
106
378514
1790
06:21
To give you an idea of what that means:
107
381006
2648
06:24
that's the diameter of the smallest neuron in the human brain.
108
384442
4002
06:29
So that means we can focus through skull and brain to a neuron.
109
389300
4450
06:34
No one has seen this before, we're doing this for the first time here.
110
394104
3634
06:38
It's not impossible.
111
398207
1589
06:39
(Applause)
112
399820
1942
06:41
We made it work with our system, so we've made a breakthrough.
113
401786
2982
06:44
(Laughter)
114
404792
1801
06:46
Just to give an idea -- like, that's not just 50 marbles.
115
406617
2952
06:49
That's billions, trillion of photons,
116
409593
2897
06:52
all falling in line as directed by the hologram,
117
412514
3396
06:55
to ricochet through densely scattering brain,
118
415934
5071
07:01
and emerge as a focus.
119
421029
2937
07:03
It's pretty cool.
120
423990
2008
07:06
We're excited about it.
121
426022
1277
07:07
This is an MRI machine.
122
427728
2032
07:09
It's a few million dollars, it fills a room,
123
429784
2162
07:11
many people have probably been in one.
124
431970
2186
07:14
I've spent a lot of time in one.
125
434180
1540
07:15
It has a focus of about a millimeter --
126
435744
2397
07:18
kind of chunky, compared to what I just showed you.
127
438165
2833
07:21
A system based on our technology could enable dramatically lower cost,
128
441022
5658
07:26
higher resolution
129
446704
1815
07:28
and smaller medical imaging.
130
448543
2493
07:31
So that's what we've started to do.
131
451680
1869
07:34
My team and I have built a rig, a lab rig
132
454180
4228
07:38
to scan out tissue.
133
458432
1856
07:40
And here it is in action.
134
460797
1666
07:42
We wanted to see how good we could do.
135
462932
2142
07:46
We've built this over the last year.
136
466535
2061
07:49
And the result is,
137
469626
1525
07:51
we're able to find tumors
138
471814
4337
07:56
in this sample --
139
476175
1170
07:57
70 millimeters deep, the light going in here,
140
477369
3141
08:00
half a millimeter resolution,
141
480534
2214
08:02
and that's the tumor it found.
142
482772
2288
08:05
You're probably looking at this,
143
485526
2461
08:08
like, "Sounds good, but that's kind of a big system.
144
488011
4991
08:13
It's smaller than a honking-big MRI machine,
145
493026
4551
08:17
monster MRI machine,
146
497601
1350
08:18
but can you do something to shrink it down?"
147
498975
2165
08:22
And the answer is:
148
502038
1784
08:23
of course.
149
503846
1170
08:25
We can replace each big element in that system
150
505040
3620
08:28
with a smaller component --
151
508684
1595
08:30
a little integrated circuit,
152
510303
1897
08:32
a display chip the size of a child's fingernail.
153
512224
4139
08:37
A bit about my background:
154
517451
1555
08:39
I've spent the last two decades inventing, prototype-developing
155
519030
6235
08:45
and then shipping billions of dollars of consumer electronics --
156
525289
4959
08:50
with full custom chips --
157
530272
2305
08:52
on the hairy edge of optical physics.
158
532601
2736
08:55
So my team and I built the big lab rig
159
535919
4682
09:00
to perfect our architecture and test the corner cases
160
540625
4742
09:05
and really fine-tune our chip designs,
161
545849
2191
09:08
before spending the millions of dollars to fabricate each chip.
162
548064
3649
09:12
Our new chip inventions slim down the system, speed it up
163
552318
4672
09:17
and enable rapid scanning and de-scattering of light
164
557014
4083
09:21
to see deep into our bodies.
165
561121
1867
09:23
This is the third key to enable better, faster and cheaper health care.
166
563498
5525
09:33
This is a mock-up of something that can replace the functionality
167
573577
6705
09:40
of a multimillion-dollar MRI machine
168
580306
2970
09:43
into a consumer electronics price point,
169
583300
2690
09:46
that you could wear as a bandage, line a ski hat, put inside a pillow.
170
586014
5333
09:51
That's what we're building.
171
591882
1672
09:53
(Applause)
172
593578
1169
09:54
Oh, thanks!
173
594771
1279
09:56
(Applause)
174
596074
2975
09:59
So you're probably thinking,
175
599073
2139
10:01
"I get the light going through our bodies.
176
601236
2833
10:04
I even get the holography de-scattering the light.
177
604911
2934
10:08
But how do we use these new chip inventions, exactly,
178
608656
2867
10:11
to do the scanning?"
179
611547
1255
10:13
Well, we have a sound approach.
180
613903
2066
10:16
No, literally -- we use sound.
181
616411
1866
10:18
Here, these three discs represent the integrated circuits
182
618949
4100
10:23
that we've designed,
183
623073
1465
10:24
that massively reduce the size of our current bulky system.
184
624562
4847
10:30
One of the spots, one of the chips, emits a sonic ping,
185
630157
3420
10:34
and it focuses down,
186
634369
1654
10:36
and then we turn red light on.
187
636696
2081
10:39
And the red light that goes through that sonic spot
188
639347
3396
10:42
changes color slightly,
189
642767
2360
10:45
much like the pitch of the police car siren changes
190
645680
3005
10:48
as it speeds past you.
191
648709
1467
10:52
So.
192
652042
1241
10:53
There's this other thing about holography I haven't told you yet,
193
653307
3301
10:56
that you need to know.
194
656632
1309
10:58
Only two beams of exactly the same color can make a hologram.
195
658427
4769
11:03
So, that's the orange light that's coming off of the sonic spot,
196
663800
5356
11:09
that's changed color slightly,
197
669180
2183
11:11
and we create a glowing disc of orange light
198
671387
3649
11:15
underneath a neighboring chip
199
675060
1619
11:17
and then record a hologram on the camera chip.
200
677212
3627
11:21
Like so.
201
681362
1215
11:22
From that hologram, we can extract information just about that sonic spot,
202
682601
5333
11:27
because we filter out all of the red light.
203
687958
2934
11:32
Then, we can optionally focus the light back down into the brain
204
692037
3927
11:35
to stimulate a neuron or part of the brain.
205
695988
3183
11:39
And then we move on to shift the sonic focus to another spot.
206
699195
5104
11:44
And that way, spot by spot, we scan out the brain.
207
704323
3960
11:49
Our chips decode holograms
208
709309
2643
11:51
a bit like Rosalind Franklin decoded this iconic image of X-ray diffraction
209
711976
5764
11:57
to reveal the structure of DNA for the first time.
210
717764
3111
12:01
We're doing that electronically with our chips,
211
721379
3192
12:04
recording the image and decoding the information,
212
724595
3737
12:08
in a millionth of a second.
213
728356
1828
12:10
We scan fast.
214
730612
1675
12:13
Our system may be extraordinary at finding blood.
215
733625
3333
12:17
And that's because blood absorbs red light and infrared light.
216
737534
3881
12:21
Blood is red.
217
741439
1563
12:23
Here's a beaker of blood.
218
743995
1388
12:25
I'm going to show you.
219
745407
1467
12:27
And here's our laser, going right through it.
220
747704
3067
12:31
It really is a laser, you can see it on the -- there it is.
221
751180
2929
12:34
In comparison to my pound of flesh,
222
754133
3941
12:38
where you can see the light goes everywhere.
223
758098
2428
12:41
So let's see that again, blood.
224
761415
2067
12:44
This is really key: blood absorbs light,
225
764303
2703
12:47
flesh scatters light.
226
767989
2206
12:51
This is significant,
227
771133
1388
12:52
because every tumor bigger than a cubic millimeter or two
228
772545
3865
12:56
has five times the amount of blood as normal flesh.
229
776434
3779
13:01
So with our system, you can imagine detecting cancers early,
230
781069
4622
13:05
when intervention is easy,
231
785715
2140
13:07
or tracking the size of your tumor as it grows or shrinks.
232
787879
3933
13:12
Our system also should be extraordinary at finding out where blood isn't,
233
792338
5136
13:17
like a clogged artery,
234
797498
1722
13:19
or the color change in blood
235
799244
2001
13:21
as it carries oxygen versus not carrying oxygen,
236
801269
3588
13:24
which is a way to measure neural activity.
237
804881
2800
13:28
There's a saying that "sunlight" is the best disinfectant.
238
808872
4634
13:33
It's literally true.
239
813530
1512
13:35
Researchers are killing pneumonia in lungs by shining light deep inside of lungs.
240
815563
6162
13:41
Our system could enable this noninvasively.
241
821749
3254
13:45
Let me give you three more examples of what this technology can do.
242
825932
4279
13:50
One: stroke.
243
830592
1389
13:52
There's two major kinds of stroke:
244
832601
2267
13:54
the one caused by clogs
245
834892
2152
13:57
and another caused by rupture.
246
837068
1961
13:59
If you can determine the type of stroke within an hour or two,
247
839053
4098
14:03
you can give medication to massively reduce the damage to the brain.
248
843175
4708
14:08
Get the drug wrong,
249
848358
1452
14:10
and the patient dies.
250
850675
1341
14:12
Today, that means access to an MRI scanner within an hour or two of a stroke.
251
852752
4728
14:18
Tomorrow, with compact, portable, inexpensive imaging,
252
858306
4271
14:22
every ambulance and every clinic can decode the type of stroke
253
862601
3830
14:26
and get the right therapy on time.
254
866455
2283
14:30
(Applause)
255
870396
4021
14:34
Thanks.
256
874441
1150
14:36
Two:
257
876155
1150
14:38
two-thirds of humanity lacks access to medical imaging.
258
878085
4596
14:43
Compact, portable, inexpensive medical imaging can save countless lives.
259
883394
5024
14:49
And three:
260
889347
1555
14:50
brain-computer communication.
261
890926
2062
14:53
I've shown here onstage our system focusing through skull and brain
262
893529
4348
14:57
to the diameter of the smallest neuron.
263
897901
2730
15:01
Using light and sound, you can activate or inhibit neurons,
264
901187
4287
15:05
and simultaneously, we can match spec by spec
265
905498
3492
15:09
the resolution of an fMRI scanner,
266
909014
2706
15:11
which measures oxygen use in the brain.
267
911744
2508
15:14
We do that by looking at the color change in the blood,
268
914276
3341
15:17
rather than using a two-ton magnet.
269
917641
2333
15:21
So you can imagine that with fMRI scanners today,
270
921541
6152
15:28
we can decode the imagined words, images and dreams of those being scanned.
271
928617
4557
15:33
We're working on a system that puts all three of these capabilities
272
933665
3317
15:37
into the same system --
273
937006
1547
15:38
neural read and write with light and sound,
274
938577
3214
15:41
while simultaneously mapping oxygen use in the brain --
275
941815
4127
15:45
all together in a noninvasive portable
276
945966
2587
15:48
that can enable brain-computer communication,
277
948577
2786
15:51
no implants, no surgery, no optional brain surgery required.
278
951387
4326
15:56
This can do enormous good
279
956061
2080
15:58
for the two billion people that suffer globally with brain disease.
280
958165
4533
16:04
(Applause)
281
964020
5135
16:09
People ask me how deep we can go.
282
969179
1890
16:11
And the answer is: the whole body's in reach.
283
971093
2929
16:14
But here's another way to look at it.
284
974046
2036
16:20
(Laughter)
285
980800
1404
16:22
My whole head just lit up, you want to see it again?
286
982228
2612
16:24
Audience: Yes!
287
984864
1230
16:26
(Laughter)
288
986118
1417
16:28
MLJ: This looks scary, but it's not.
289
988442
2221
16:31
What's truly scary is not knowing about our bodies,
290
991046
2983
16:34
our brains and our diseases
291
994053
1992
16:36
so we can effectively treat them.
292
996069
1945
16:38
This technology can help.
293
998038
1658
16:39
Thank you.
294
999720
1151
16:40
(Applause)
295
1000895
5454
16:46
Thank you.
296
1006373
1151
16:47
(Applause)
297
1007548
1150
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