That Neuroscience Guy - The Neuroscience of Mind Reading

Episode Date: November 25, 2023

You'll often see lie detector tests in modern media, where large machines are used to determine if someone is telling the truth. But does that actually work? And is there a better way to look into someones mind and see what they're thinking? In today's episode of That Neuroscience Guy, we discuss the neuroscience behind reading someone's mind. 

Hi, my name is Olof Kregolsen, and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to the podcast. So last week, I was at the Society for Neuroscience meeting in Washington, D.C., and it's a conference. It's a really large conference. In fact, it's the biggest neuroscience conference in the world. Last week, there was over 25,000 neuroscientists and medical professionals from around the world there,

and it covers the complete span of neuroscience. It covers people who are looking through microscopes to look at individual cells to see what's going on, to people that are doing whole body imaging and trying to figure out what's going on in the brain, to the people that study animals, to the people that even just do the history of neuroscience. And I like to wander around and see what's new, like what's cutting edge neuroscience. And I saw some pretty cool stuff. So today on the podcast, the neuroscience of mind reading. So let's start with,

I guess, a simple form of mind reading that most of you are familiar with, which is the lie detector or polygraph. You might have seen them on a television show or a movie where the police are trying to figure out if someone's lying or not. And the way a polygraph works is pretty straightforward. The person is connected to, you know, sometimes four, sometimes as many as six or seven sensors. And basically the machine is just recording the input from those sensors. And one of the things that it records is a person's breathing rate to monitor changes in breathing rate. It also records a person pulse, typically also blood pressure and perspiration. And sometimes

they'll even look for body movements. So to see if someone's twitching a bit or not. And basically the way the test works is the operator is looking at the output of these sensors on a piece of paper. I know sometimes on TV shows, it looks like a single line, but there would actually be lines for every single sensor.

So it's the combination of information that the person is looking for. And what they do is they ask a couple of simple control questions. That's to set the stage. And they're really just trying to get a feel for what your average response is for these things. And then they get into the challenging questions. So hopefully you've never committed a crime. But if you've committed a crime, they might ask you some information about the crime scene or about what took place, asking if you were there, asking if you knew the person

that was involved or the other people that were involved. And what the operator is trying to do is look for changes in the pattern. They're trying to discern if there's sort of a spike in one of these signals or multiple signals. And by doing so, they're reading your mind, right? They're able to say this person is lying. Now, as you probably know from watching too much TV or reading too many books about these kind of subjects, is that people can spoof a polygraph. It's not perfect.

Basically, the operator relies on considerable expertise to interpret those results and decide whether you're lying or not. But people can be coached to spoof a polygraph, which is why it's not perfect. Now, I wasn't looking at polygraphs in terms of mind reading. It was using neuroscience technology to appear inside someone's mind. It was using neuroscience technology to appear inside someone's mind. Perhaps one of the coolest research presentations I saw was on using fMRI, so functional magnetic resonance imaging, to tell if someone had seen something before. So what the researchers did is they got pictures of places that they knew you were familiar with,

and then they got pictures of which they were fairly certain you had never seen before. So imagine the living room of your own house or your friend's house or your parent's house compared to the living room of a stranger's house that you'd never seen before. And people went in the fMRI scanner and they show them these pictures. All right. So they go, here's a picture of, you know, a stranger's living room. Here's a picture of a living room you're familiar with. And what they're able to do with that data is they're able to determine that, hey, you recognize the picture. So in terms of, you know, the polygraph or the lie detector,

this is way more powerful because this is the person's brain responding in a way that they know they recognize the scene. And from my discussions with the research team, there's no way to spoof this, right? They're looking at a change in blood flow in the brain and it's literally your brain saying, hey, I recognize that. And if you think about how that would work, you know, there's a spatial location to it. Imagine you were there and it was a crime of some sort that you were a part of. Well, there'd be an emotional response to the event, most likely. And there's visual recognition processes. So what happens is they can decode this information and literally decide,

this is one that you've seen before. This is one that you haven't seen before. And in principle, if used in court, it would be the ultimate form of lie detector in a form of mind reading. Now, there was some even crazier stuff than that. Another presentation I saw by an fMRI research group was doing something similar, but what they were able to do and what they did was they showed you pictures of objects. So a fork, an apple, a car, and what happens is your brain responds to these objects. If you think just a visual recognition, you know, the ones I talked about, you know, a piece of fruit versus a car, these are processed in slightly different parts of the brain. And even for individual items, it's again slightly different. And what the research team was able to do was in real time predict what the person was looking at.

Now, they obviously knew what the person was looking at because they're showing it to them, right, on a computer screen while they're in the fMRI scanner. But the computer doesn't know what image they're seeing. It's just decoding the brain activity. And it's able to say, this person was looking at a fork. This person was looking at an apple. This person was looking at a house. So again, a kind of a cool form of mind reading where the computer is literally decoding your brain activity to figure out what you're looking at. One that was a bit more near and dear to my heart was a follow-up

of a study that I talked about a long time ago, but it's one I use in class all the time. And yet again, it's another form of mind reading. And again, it's using this fMRI technology. In this case, the researchers were having people play what's called the ultimatum game. Now, in the ultimatum game, it's kind of a weird game. It's based on the premise that there's two people. One person has an amount of money and the other person is waiting to get an offer on that money, like how that money gets shared. So let's say I have the money and it's a hundred dollars. I could look at the other person and say, I'm going to give you $50. And the other person's job is to say yes or no, right? If they say yes, then the split happens and the people actually

get paid. And if they say nobody gets the money. Now, when people play the ultimatum game, the key rule is you only play one time. So if you got an unfair offer, let's say I offered you $20 and said I was going to keep $80. If we were going to play multiple times, then from a rational perspective, it makes sense for you to say no to an unfair offer because you're sending me a message you're basically telling me hey you know I'm not gonna put up with this right you need to you need to give me a better offer but if you're only gonna play one time ever then it actually makes sense to say yes to any offer even if I said I'm gonna keep $99 and offer you a single dollar, then you should take

it because $1 is better than no dollars. Now, this study was run quite a while ago, but what they're doing with it now is when people do this in an fMRI scanner, they're able to scan through the EEG data and they know the decision the person's going to make, accept the offer, reject the offer, before they actually make the decision. So by reading their brain activity, they can mind read or predict what the person's going to do. And I found that fascinating because you're dealing with a technology that is allowing people to read your mind. Like in all of these cases I've talked about, they know whether you recognize a visual scene, they know what objects you're looking at, and they know what decisions you're going to make. And you might think, okay, well, it's an fMRI scanner, you know, how often are you going to be in an fMRI scanner? But this was the other cool part of what I saw at

the Society for Neuroscience meeting. There were other researchers who were paralleling these studies, but they were using EEG or electroencephalography or brainwaves, and they were using FNIRs, functional near-infrared spectroscopy. And in the cases of EEG and FNIRs, the senses are now portable and mobile. You can go online and you can buy a Muse S for a couple of hundred dollars. It's a great mobile EEG system. Or you can go online and buy a Mendi. It's a mobile FNIR system, again, for a couple of hundred bucks. And people are using these detectors, right? They're using these signals to do similar forms of mind reading. Now, it's not nearly as sophisticated at this stage because the reality is EEG sensors and FNIR sensors are quite coarse. But these tools to read people's minds in the real

world are already out there and being used. And it is possible at some point people could do this. They could read your mind. Now, i know some people get scared about this and to be fair there was a good debate about neuroethics you know just because we can do it should we do it and that's something that will have to be discussed but i find it fascinating that this mind reading technology is out there you know typically we think what's going on in our head is private and known only to us now with these with these types of sensors, fMRI, EEG, and FNIRs, people are able to read our mind. And it's only going to get more sophisticated and more advanced. I'll share one more with you that I found fascinating.

It's, again, something that I knew about or have known about for quite a while. It's, again, something that I knew about or have known about for quite a while. But there's a group in the States that is basically using EEG sensors in the brain to control a robot skeleton. Now, that might sound a bit weird, but imagine you're a quadriplegic and you have no movement below your neck. All right. Your arms and legs are damaged due to injuries to the spinal cord. Well, this group is using EEG sensors in the motor regions of the brain to control motors on skeletons, basically a metal exoskeleton you wear. And now these people are able to walk and feed themselves and interact with objects.

Now, that technology is still being developed, but it's another form of mind reading. This technology now that we can control external devices simply by thinking about moving our body the way we normally would. Anyway, hopefully you found that interesting. I always love walking around these big conferences because the reality is the bit of not neuroscience I know is quite, you know, it's quite focused. In my lab, we study learning and decision making, and we do some applied stuff. So you don't really get to study everything and anything.

But I was walking around and I was completely fascinated by the mind reading technologies that are out there. And I hope you found that interesting as well. Anyway, don't forget, you can support us through Patreon. A couple of dollars a week or a month really helps out. All the money goes to Matt, our sound producer. He puts in countless hours editing these podcasts after I record them

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neuro side guy. Please send us ideas for future episodes. We want to know what you want to know about the neuroscience of daily life. And then of then of course finally thank you so much for listening to the podcast please subscribe and i'll be back to you soon with another neuroscience bite my name is oliv krigolsen and i'm that neuroscience guy thank you so much for listening