Mind Reading
Vsauce
0:05 Mind reading?
0:06 Of course not.
0:08 I love reading.
0:11 Look, mind reading might sound
0:14 like pseudoscientific— pardon my language— bullshoot.
0:18 But its scientific counterpart, thought identification,
0:21 is very much a real thing.
0:23 It's based in neuroimaging and machine learning,
0:26 and what's really cool is that experiments in mind
0:29 reading aren't just about spying on what someone is thinking.
0:33 They're about figuring out what thoughts are even made of.
0:37 I mean, when I think of something,
0:39 what does that mental picture actually look like?
0:43 What resolution is it in?
0:44 How high fidelity is a memory, and how do they change over time?
0:49 Well, in this episode, I'm going to look at how reading
0:52 people's minds can help us answer these questions.
0:54 My journey begins right here at the University of Oregon.
0:58 I'm meeting with Dr.
0:59 Brice Kuhl from the Kuhl lab.
1:01 He's a neuroscientist who uses neuroimaging and machine learning
1:04 to figure out what people are thinking without them telling him.
1:31 So tell me what you're doing here.
1:33 Well, I'm in the cognitive neuroscience program here, and I study human memory.
1:38 My lab primarily uses neuroimaging methods,
1:41 so we do a lot of work using functional magnetic resonance imaging, or fMRI.
1:45 And how do you use fMRI to investigate memories?
1:49 We're looking at the pattern of neural activity.
1:51 When you form a memory, there's a certain pattern.
1:54 And we can record that pattern and then test whether
1:58 that pattern is reinstated or reactivated at a later point,
2:01 like when you're remembering it.
2:02 Does that mean we can look at the patterns of brain
2:05 activity and deduce what it is that is being remembered,
2:09 or recalled, or even just thought?
2:11 Yes, and so we call that decoding.
2:13 So it basically takes your input pattern as some
2:17 pattern of activity that we record while you're remembering something.
2:21 And we make a prediction about what you're remembering.
2:23 You can see how this sounds like mind reading.
2:27 [laughs] Yes.
2:27 It sounds like that.
2:28 So, Brice, what are you going to do to me today?
2:32 So, what we're going to be doing today is uncharted territory for us.
2:36 So we're going to be trying out a kind of new variant of the experiment on you.
2:40 So I can't guarantee any particular results.
2:42 But it represents where the field is and where we're trying to go.
2:46 Today, you're going to participate
2:47 in an experiment where you'll be studying faces.
2:50 So we're going to have you study 12 pictures of celebrities.
2:53 People I already am familiar with.
2:54 -People that you know, yeah.
2:56 -Okay.
2:56 And you're going to try to remember those pictures.
2:59 Then we're going to have you go into the MRI scanner.
3:01 Try to bring that picture to mind as vividly as possible.
3:04 And we're going to be recording your brain
3:06 activity as you try to imagine these pictures.
3:08 We're going to try to build the face.
3:10 Essentially draw a picture of what you're remembering.
3:12 -A picture?
3:13 -A picture.
3:14 An actual picture that we can print out and I could, like, hang on my wall.
3:17 [laughs] If you wanted.
3:19 [Michael] The first step is for me to memorize the 12
3:23 specific celebrity photographs Brice will later try to detect me thinking about.
3:28 I sat down to do this graduate student, Max.
3:33 The success of his predictions depend, in part,
3:35 on my ability to recall these faces
3:37 as vividly as possible while inside the fMRI.
3:43 All right, so...
3:44 [sighs] I think I have a pretty good memory of all of those.
3:50 -Great.
3:51 -I feel the stakes are high.
3:53 With the celebrity faces hopefully memorized, it's time for the next step:
3:58 going through the metal detector and into the fMRI,
4:01 where Brice will record and monitor my brain activity,
4:04 and then later feed it into his algorithm to rebuild the faces.
4:08 This will be the first time he's
4:10 attempted to reconstruct faces from long-term memory, which is very difficult,
4:13 because we're relying on how clearly I can
4:15 remember the celebrity photos I saw an hour ago.
4:19 I love its eyes.
4:20 Look at that.
4:21 [woman] Wouldn't the kid be like, "It's going to eat me"?
4:31 An fMRI monitors the activity within the brain by dividing
4:34 it up into thousands of small cubes called voxels, or volumetric pixels.
4:39 Each of these voxels contains hundreds of thousands of neurons.
4:43 Using fMRI, we are able to detect blood flow within these voxels,
4:47 which means that that part of the brain is active.
4:50 If I'm shown several pictures of people with mustaches,
4:53 my brain will react to the features for each face.
4:56 But there will be a common area of my brain that is engaged throughout.
5:00 That may be the area of my brain that reacts to mustaches.
5:04 So later, when I imagine a face, if Brice notices that area is engaged,
5:09 he can predict that I am thinking about a mustache.
5:13 So right now Michael's in the scanner,
5:15 and he's seeing words appear on the screen one at a time,
5:18 and he's trying to visualize the face,
5:20 remember the face in as much detail as possible.
5:23 What you can see here are the images that we're acquiring.
5:25 We get one of these brain volumes every two seconds.
5:28 So these are refreshing in real time as we collect the images.
5:32 [Michael] With part one of the fMRI session over, it's time for part two,
5:37 where Brice and his team will learn the language of my brain activity,
5:41 so they can later decode by brain scans.
5:44 Hi, Michael.
5:45 You doing okay still?
5:46 [Michael] Yup.
5:48 They'll show me hundreds of unique faces,
5:50 and record how my brain reacts to certain facial characteristics.
5:54 They will then use this information to reconstruct the celebrity
5:59 faces I thought about during the first phase of the scan.
6:03 Really, the more faces that we can show Michael, the better.
6:05 So we're going to basically keep him in there as long as he's comfortable.
6:09 [Michael] Two hours was the maximum time we could get in the fMRI.
6:13 But I was able to look at over 400 faces,
6:17 which should be enough to get some pretty interesting results.
6:20 Hey, Michael, you did it.
6:21 That was great.
6:22 We're going to come get you out.
6:23 [Michael] All right.
6:33 Yeah, so these just show some of the pictures
6:34 that we were taking while you were in there.
6:36 Some images of your brain.
6:38 Now we are going to crunch some numbers.
6:39 Max is going to analyze your data.
6:42 We'll meet up again tomorrow, where we'll look at the results,
6:45 where we try to actually reconstruct the face
6:47 images from the brain data that we just collected.
6:49 All right.
6:50 Well, see you tomorrow.
6:51 All right.
6:51 Thanks a lot.
6:52 Max, thank you as well.
6:53 I can't wait.
6:54 You better pull an all-nighter.
6:55 I want this data to be perfect.
7:04 All right, so I am back at Dr.
7:06 Kuhl's lab.
7:06 Overnight, his team crunched the data,
7:08 and I can't wait to see what they think they saw me thinking.
7:15 How are my results?
7:17 I think they look good.
7:18 We're going to take a look in just a moment here.
7:20 All right, I can't wait.
7:22 -So can I just take a seat?
7:23 -Yeah, have a seat.
7:24 All right, so...
7:26 first of all...
7:28 what am I seeing?
7:29 Oh, okay, well, these are the pictures I actually memorized.
7:32 -That's right.
7:32 -And this is what you've reconstructed from my imagination.
7:37 -That's right.
7:38 -Oh, wow.
7:39 Okay.
7:40 [Brice] Okay, so this is one of the reconstructions that was generated.
7:44 [Michael] Interesting.
7:46 [Max] So that's John Cho.
7:47 [Michael] Not bad.
7:49 Not bad.
7:50 -Can we see the side by side?
7:52 -Yeah.
7:53 [Michael] I see, you know,
7:55 similarities in the kind of facial expressions in general.
8:00 You know, you could almost see the hairline matching here.
8:02 The shape of the face I also thought was— It kind of had a square shape to it.
8:06 -Yes.
8:06 Yes.
8:07 -So those are the things that came out to me.
8:09 And so when I was visualizing this image of John Cho,
8:13 the squareness of the face was the first, most salient thing.
8:16 I just kept thinking, he was the square guy.
8:19 Excellent, all right.
8:23 [Brice] So that's Megan Fox.
8:26 [Michael] Mm-hmm.
8:28 You're going to show us the— side by side.
8:30 [Michael] The side by side.
8:31 Right.
8:31 [Brice] You can see the picture you actually saw,
8:33 and that's the reconstruction we generated.
8:36 I'll you this.
8:37 Megan Fox, I was not able to have a really clear picture in my mind.
8:42 For some reason, this image of her was really
8:44 hard for me to bring back into my mind.
8:47 The sternness in the face was something that I did pick up on.
8:50 So I did sense that there was— It looked feminine.
8:53 And you picked up on the sternness.
8:55 And so together, that produces a match.
8:58 [Michael] Keep in mind that Brice and his team have read these from my memory.
9:02 But when I remember a face,
9:04 do I picture every detail simultaneously with photographic accuracy?
9:09 Or do I just attend to a few at a time?
9:10 By reading my mind, they may be seeing how bad my memory is, and how it works.
9:15 -Me!
9:16 Me!
9:16 -[Brice laughs] Okay,
9:19 so that is your reconstruction of me thinking about this image of myself.
9:24 [Brice] That's right.
9:26 Where'd the beard go?
9:28 [Brice] I don't know.
9:29 I was hoping you could tell me.
9:31 [Michael] For instance, this is a picture of me remembering my own face.
9:36 It really doesn't look like me, but the question is:
9:38 how good am I at picturing myself?
9:41 I don't think of my own face that often,
9:44 so the strangeness in the result may be as much about flaws
9:46 in my own memory and mental picture of myself as flaws in the technology.
9:51 So that's Jennifer Lawrence, I believe.
9:53 [Michael] That's Jennifer Lawrence?
9:55 It looks like it's Jennifer Lawrence's much older uncle.
9:59 [all chuckle] Nothing here was too mind-blowingly close.
10:05 But this is something that you're just
10:08 starting out trying these sort of long-term memories.
10:11 What Brice and his team read in my mind might have been more
10:16 accurate if they'd shown me thousands rather
10:18 than hundreds of images in the fMRI,
10:20 because then the algorithm would have learned
10:22 the language of my brain more thoroughly.
10:24 But regardless, the quality of my memories would have still been an issue.
10:29 I mean, look what happens when memory is cut out of the equation entirely.
10:33 Brice also read my brain activity when I was looking at faces in the fMRI.
10:37 not just imagining them.
10:39 And those results were much closer than those reconstructed from my memory.
10:44 Okay, so, what am I looking at right here?
10:47 [Brice] Okay, so what you're seeing here in the top row,
10:49 these are images that you saw while you were in the scanner.
10:53 Below that, in this bottom row, these are the reconstructions that we draw
10:57 from the patterns of brain activity we collected.
11:00 -This is from the source image.
11:03 -Right.
11:03 [Michael] These are from my brain.
11:05 -[Brice] Right.
11:06 -[Michael] They're pretty close.
11:07 Yeah, overall they were pretty close.
11:09 So not perfect.
11:11 These are— you can see there's some variability in these.
11:13 But this is consistent with what we've found before,
11:16 that the reconstructions that we generated, when you're viewing the faces,
11:20 there is some correspondence between the actual face.
11:22 So this is kind of a sanity check,
11:23 that we can actually reconstruct the images -when you're viewing them.
11:27 -Right, right.
11:28 They're pretty good.
11:31 Well, Brice, Max, thank you so much for letting me be a part of this.
11:35 I hope my data's useful.
11:36 Thank you.
11:37 It's been a lot of fun.
11:38 It's always useful for us to think about these things.
11:46 Dr.
11:47 Brice Kuhl's memory research is showing that it's
11:50 possible for a computer to read someone's mind.
11:53 To figure out what they're thinking.
11:56 But a lot of progress still needs to be made.
11:58 I mean, if you want to know what I'm thinking right now,
12:01 for example, it's still easier to just ask me to tell you.
12:05 But what if I can't tell you?
12:07 Dr.
12:08 Yukiyasu Kamitani is a researcher,
12:10 professor and pioneer exploring the frontier behind the wall of sleep.
12:17 I've come here to Kyoto University to meet with him
12:20 and to see what it's like to read not what someone is thinking,
12:24 but what someone is dreaming.
12:29 Kamitani sensei, I'm Michael.
12:31 -Hi, I'm Yuki.
12:32 -Yuki, nice to meet you.
12:33 [Michael] For the last ten years, Dr.
12:36 Kamitani has been at the forefront of machine mind reading.
12:40 The subject is, you know, ready to go in.
12:43 Similar to Brice Kuhl,
12:45 his early experiments explored reconstructing images shown to subjects
12:49 in an fMRI based on their brain activity.
12:52 In Kamitani's case, the images were black-and-white shapes,
12:55 and the reconstructions were strikingly accurate.
12:58 Recently, Kamitani has focused on using
13:01 deep neural networks and machine learning
13:04 to decipher subjects' brain activity while
13:06 they view much more complex photographs.
13:08 What you're seeing is the result of a deep neural network
13:12 processing the brain activity of a subject looking at the photograph.
13:17 This could have myriad applications in the future,
13:20 for example, in criminal investigations and interpersonal communication.
13:26 [Kamitani] This is far from perfect.
13:28 But I think you still see some, you know, eyes and, you know...
13:33 [Michael] Well, yeah.
13:34 And colors too.
13:36 [Kamitani] Yeah, to some extent, yeah.
13:39 His most current work, however, is about the subconscious.
13:42 He's attempting something extremely ambitious: recording our dreams.
13:46 Would you call yourself a sleep researcher, or a vision researcher?
13:50 Maybe a brain decoder.
13:53 A brain decoder.
13:55 That's a pretty cool job description.
13:57 Can you show me anything from what you're doing with dreams?
14:01 [Kamitani] Mm-hmm, yeah.
14:08 Dr.
14:08 Kamitani's work on dream decoding begins with a similar process to Dr.
14:12 Kuhl's: showing the test subject thousands of images while they are in an fMRI
14:17 in order to learn what the brain looks
14:18 like when it is thinking of certain things.
14:21 Once the machine-learning algorithm is pretty good
14:23 at identifying what images the subject is thinking about,
14:26 the subject is placed in an fMRI with an EEG cap on their head,
14:31 and invited to fall asleep.
14:33 When the EEG waves indicate that the person is dreaming,
14:36 the algorithm predicts which kinds of things
14:39 the subject is most likely dreaming about.
14:41 Right now, the algorithm looks for 20 categories.
14:45 Things like buildings, transportation, and characters in a language.
14:50 Researchers then awaken the subject, ask them what they were dreaming about,
14:55 and see if the algorithm's prediction and the person's recollection match.
14:59 Here is actual data from one of Kamitani's experiments.
15:03 Below is a word cloud of categories.
15:05 The name of each category get bigger or smaller in real time
15:09 based on the probability that they are present in the subject's current dream.
15:13 Now, as you can see, activity is currently strongest
15:15 for the category "character," meaning written language.
15:18 At this point the subject was awoken, and this is what they reported.
15:29 That's pretty spooky.
15:32 -[laughs] -Right?
15:32 I mean, you— you spied on their dream.
15:36 Yeah, in a way.
15:38 But...
15:39 the accuracy's not that great, so...
15:42 Well, the accuracy's not that great but, you know,
15:44 my normal accuracy for guessing people's dreams is zero.
15:46 Right.
15:48 While continuing his research into predicting the content of dreams, Dr.
15:52 Kamitani is embarking on his newest project:
15:54 actually reconstructing images from our dreams.
15:58 So you've brought some of the reconstructions that your lab has created...
16:02 Mm-hmm.
16:04 ...of dreams.
16:17 Right, they all look like dreams about blobs.
16:20 [Kamitani] Yeah.
16:21 I mean, I want to just take a step back and...
16:24 appreciate that what we're looking at on this screen are,
16:28 in a way, some of the first photographs of a dream.
16:31 Mm-hmm.
16:33 We are looking at the earliest phase of revolutionary research.
16:38 One day, we may able to have images, or even record movies, of our own dreams.
16:42 And Dr.
16:43 Kamitani is the only person in the world doing this so far.
16:47 He's a lone explorer journeying into our subconscious.
16:50 So this work hasn't even been published yet.
16:53 No.
16:55 -Thank you for showing it to me.
16:57 -[laughs] The insights that researchers like Dr.
17:04 Kuhl and Dr.
17:05 Kamitani might be capable of achieving in the future
17:09 because of mind reading are difficult to fully fathom.
17:13 But let's slow down for a second,
17:15 because we're talking about a technology that can
17:18 know us better than we know ourselves.
17:21 Should we really be doing this?
17:23 Well, to address that question, I'm going to meet with an expert in ethics,
17:27 neuroscience and artificial intelligence: Julia Bossmann.
17:32 She's the director of strategy at Fathom Computing,
17:34 a council member of the World Economic Forum,
17:37 an alum of Ray Kurzweil's Singularity University,
17:40 and a former president of the Foresight Institute,
17:43 a think tank specializing in future technologies and their impacts.
17:50 Julia, thanks for taking some time to chat.
17:52 -Yeah, of course.
17:53 -You are the perfect person for me to bring these questions to.
17:55 -Mm-hmm.
17:56 -And they're deep questions.
17:57 But I think they're extremely important,
17:58 and they're becoming more and more pressing.
18:00 I think we're living in such an interesting time right now,
18:04 because we're in this time where brains
18:05 and machines are actually moving closer together.
18:07 So when it comes to being able to look at brain activity,
18:12 where are the ethical lines here?
18:15 How private should my internal thoughts be?
18:17 Like with any powerful technology, it depends on the hands that wield it.
18:22 All these new technologies are things
18:25 that can make whoever uses them more powerful.
18:28 So we want to not blame the technology,
18:30 but we want to— how is it being used, and who is using it?
18:35 So how do we make sure that this technology is in the right hands?
18:39 So I think it's very important to involve people who act
18:42 on policy and law to understand what is coming in the future.
18:48 I am hopeful about the collaborative aspect of it.
18:51 Let's talk about the good things now.
18:53 I mean, what are the applications here?
18:56 Yeah, so if we think about the late Stephen Hawking, for example,
18:59 if he had a way of richer interfacing with the world or with computers,
19:05 we can only imagine what he could have shared with us.
19:08 Those with locked-in syndrome, right?
19:10 They are there.
19:11 They know that they are there.
19:13 But we just need something to look into their brain
19:15 to see what it is that they are trying to say, -or what they're feeling.
19:19 -Right, exactly.
19:20 So, what do you say to people that have that kind of fear of technology,
19:26 of us surrendering our true natural selves to technology?
19:31 There is something enticing about getting to the next level of what
19:37 some people might call a human evolution or civilization development, and so on.
19:43 In a way, we are already not living natural lives, right?
19:46 Because then most of us would die before the age of, I don't know, 30 or 40.
19:51 We would have all kinds of diseases.
19:53 We would not wear this clothing.
19:55 We wouldn't have eyeglasses or contact lenses.
19:58 We wouldn't have antibiotics.
19:59 [Julia] We are already kind of very futuristic
20:03 cyborgs if we compare ourselves to the human
20:06 that was living 10,000 years ago and was
20:09 genetically almost identical with who we are now.
20:11 [Michael] Yeah, we really are.
20:17 In order to understand cognition, right now we basically have to either just
20:22 ask people to talk about what they're thinking, or observe their behavior.
20:26 But reading thoughts directly would be a lot better.
20:30 That is how Dr.
20:31 Kuhl is studying memory, and it's how Dr.
20:35 Kamitani is studying sleep and dreams.
20:38 But even though the technology has a long way to go,
20:40 it's easy to see how ethical questions could become an issue.
20:44 Well, here's the thing: there is no such thing as a totally wild human.
20:51 We are co-evolving with technology.
20:55 Humans and technology today are inseparable.
21:00 Now, it's true that we need to be careful about every new thing we do,
21:03 but we cannot change the fact that they will happen.
21:08 It's a story we've lived through again and again.
21:11 You know, we could have sat around forever debating whether or not
21:15 a speed limit should exist and who should have the authority to enforce it.
21:19 But we didn't.
21:21 Instead, we went ahead and invented cars,
21:24 and responsibly figured out the details as we went along.
21:29 Ethical questions about new technologies do
21:31 the most good when they facilitate the technology,
21:35 not when they needlessly hinder progress.
21:40 So follow your dreams.
21:41 And, as soon as you can, show them to me.
21:44 And, as always, thanks for watching.