This month we’re pondering the mysterious mind - what is it? Are us humans unique in having one? And where does the brain fit in? Plus we chat over some of the latest neuroscience news with local experts...
In this episode
01:05 - Conference call: video on or off?
Conference call: video on or off?
Helen Keyes, ARU; Duncan Astle, Cambridge University
It's time for some Naked Neuroscience news! And if you’re dialling in to a remote meeting, do you have your camera on, or off? Well the paper that Anglia Ruskin University's perceptual psychologist Helen Keyes has looked at this month has been looking at how group decision making stacks up with videos on vs off, and she told Katie Haylor all about it...
Helen - For a lot of species, including humans, coming together as a group to solve problems is useful. And we call this collective intelligence. And previous research has shown that synchronising our non-verbal cues plays a key role in our ability to collaborate with each other and in our collective intelligence. So our ability to solve problems together.
Katie - What kind of cues are we talking about Helen?
Helen - So here, we're talking about synchrony in facial muscle activity. So essentially your facial expression and also what we call prosodic cues, which is essentially how you are using your voice - so your pitch, the rise and fall of your voice, the melodic part of your voice really. These are particularly important for cohesion within a group and they aid collaboration.
Katie - So right then, you went down at the end of your sentence, when you said "collaboration". Is that the kind of inflection that you're talking about? You're communicating information to me that you've finished your point.
Helen - That's exactly right. That prosody contains communication, but also the emphasis we place on words, how we stress words, the pitch and the speed at which we're talking, the quality of our voices, all of that comes together to form our prosody. So another key non-verbal cue that predicts our collective intelligence is equality in conversational turn-taking - how willing we are to take turns when we're speaking to each other and to use cues to understand that one person has finished speaking on it's now the next person's turn.
Katie - I find this so difficult, Helen. I find it really hard not to interrupt people! Partly it's an internet lag, which isn't helpful. But if I'm not in front of somebody face to face, I think I do quite often interrupt people and it's difficult.
Helen - You're not at all alone in that. And we are finding in general - there are some side studies looking at turn-taking using video conferencing - and without those natural cues of being with somebody, we are actually a lot worse at knowing when to take turns in a conversation.
Katie - So what did they do to try and look at this?
Helen - Studies so far have largely focused on these behaviours in face-to-face environment. But this study wanted to look at how we use these cues, synchronise ourselves to each other over video calls and also over calls that are audio only. They wanted to see what would the same cues predict our collective intelligence.
They got 99 pairs of people. And they asked them to complete a series of collective intelligence tests, essentially some group problem-solving tests. So where you would have to come together to make decisions or generate ideas together. And half of these pairs did these tests over a video call where they could see each other and hear each other. And the other half of the pairs, did it on an audio only call. The research also measured how in sync they were. And they did this by looking at their facial expressions. So they recorded their facial expressions and used software to detect movements and expressions and matched them up with each other. And they also recorded the participants' prosody. So they had software looking at people's pitch and loudness and voice quality, and even frame to frame differences in their speech and they match that up.
And finally, they looked at speaking turn inequality. So how good people were at conversational turn-taking.
And the results showed that - well, the good news is there was no difference in collective intelligence scores depending on whether participants used video and audio, or just audio alone. However, video calling and audio calling involved participants using different methods to synchronise with each other. So for video calling facial synchrony significantly predicted the collective intelligence scores and this not surprisingly, wasn't true for the audio only calls.
However prodosic synchrony, so syncing up how you're using your voice and how you're using language, that significantly predicted collective intelligence overall across both types of media. And this was higher in the audio only condition. That was a bit surprising. So when you didn't have any video, you did better at linking up and having that prosodic synchrony with each other. And that's quite interesting because when you were just using audio only, you were actually better at the conversational turn-taking. And that led to this better synchrony in your prosody, this better communication between people, which in turn led to better collective intelligence scores.
So interestingly, when you have your video switched off, when it's audio only, you appear to be more tuned in to those voice cues, to the rules about etiquette, about turn-taking in a conversation, more tuned in to that. And you have essentially more pro-social behaviour in that way compared to when you're using video calling as well.
Katie - I wonder if it's partly because we're so used to talking on the phone for so many years, a lot of people feel comfortable doing that. I find video calling a bit of a distraction.
Helen - That's exactly what it is. It's the distraction of the video call. So whether you're looking at the other person or looking at your own face like I'm doing right now, it's very distracting. And it's interesting that it does lead to less good turn-taking. So even though overall, it wasn't that audio was better for collective intelligence compared to video, we can see that there's those differences. It is better in some ways it's better in that prosodic synchrony. But then of course you lose the facial expression synchrony in the audio only. And of course, something this study didn't look at was the other feature that we tend to use when we're video calling and video conferencing, which is the chat feature on the side. And I think that's a whole other study that could really be used to think about - is this helping us to synchronise with each other, because we're really getting our thoughts out there in real time? Or is this a further distraction from this pro-social synchronising that might help us to collectively solve a problem?
Katie - I'm being a bit flippant here, you know, giggling about not putting my video on. But so many people use these technologies now, professionally, do you think this study supports the idea that actually it's quite justifiable to have a professional conversation and actually not have your video on?
Helen - Absolutely. It's quite justifiable. What I would say is a mix of video on and video off probably isn't going to be any benefit. Because if some people have their video on, there's still that visual distraction. So it would possibly work better, in terms of tuning into each other's prosody and turn-taking, if we all had our cameras off. But again, missing out on that great emotional expression synchrony that we might expect with videos on.
The paper that Cambridge University cognitive neuroscientist Duncan Astle looked at this month is all about how the brain tracks volatility in the world around it - specifically, when applied to the stock market. And he told Katie Haylor about it.
Duncan - So they created a stock market game, so subjects were recruited and were paid a basic payment for being in the study. And then they were given the opportunity to earn more by making good investments. So the subjects would perform what they called the asset pricing task in an fMRI scanner. And the task displays trend lines which show you the recent history for individual stocks. And they are shown these sequentially and then you can make a decision with each one whether you want to invest, stick with your current investment or sell your current investment. And then periodically those are updated as if it’s the next day. And so overtime, what subjects are doing is making some sort of evaluation as to which stocks they want to invest in and which stocks they don't want to invest in.
Katie - But these aren't professional stockbrokers, right? These are just participants in the study.
Duncan - Exactly, they are not professional stockbrokers. They could have invested in the stock market themselves if they wanted to. The only as Joe Public. They are not professional stockbrokers .
And so each time they play, they will see 14 different stocks and they are real stocks from the S&P 500, but taken from recent history, so a 30 day window from a few months ago, before the experiment was conducted. So they’re real stocks or historical stocks. But the people themselves are not stockbrokers.
Katie - So they've put these people in a scanner so that the scientists can look at their brains whilst they're making these decisions, right? What exactly were they looking for?
Duncan - So they were interested in whether and which parts of your brain track what's gonna happen next. So does the activity in different bits of your brain make accurate predictions about what's going to happen in the future to the stock prices?
Katie - Ohh okay, so something like if it's likely to go down you see a little bit firing compared to if it goes up or something like that?
Duncan - Exactly, and you can imagine that actually when you're reading the stock market, when you see the lines appear on the screen, there's actually multiple different signals that you could extract from that visual input that will enable you to make a prediction about what's going to happen next.
Katie - Is that what they tracked then? Were they searching for different kind of indications of which way you are going to go? Are you going to invest or you're going to pull out?
Duncan - So they could track activity in different parts of the brain that are known to be associated with reward processing like the medial prefrontal cortex, the anterior insula, the nucleus accumbens, these are all areas that we know are involved in processing rewards. And in particular, they could test whether the activity in these areas tack dynamic changes that are happening in the stocks. For example, do some areas code for the relative volatility in the stock, versus other areas coding for rises in stocks? So you can imagine all of these bits of information - the volatility, the rising of stock, the decreasing of stock, could all provide you with information that might guide your behaviour in the future. And they were interested in whether different parts of the brain track these different types of signal.
Katie - What did they find then, once they looked at these people making these decisions?
Duncan - Looking at peoples behaviour, people’s choices didn't predict the next day's stock prices, which is reassuring. But the stock prices themselves did. Just like in a real stock market when things rose one day, they were more likely to decrease the next and vice versa. So the idea is that this kind of predictability of the stock market provides the participants with the information that guides their choices.
Katie - It's just really saying that the stock market is volatile!
Duncan - Exactly. And the trends that you see in one day do make some predictions about what might happen the next day.
Katie - So you can get kind of good at playing the stock market?
Duncan - Yeah, exactly right. So some people will get very well tuned to knowing “this stock’s been climbing for five days straight now, I think we're pretty close to what's called an inflexion point” - where it’ll reach its peak and people will start selling off the stocks and it will start to go back down again.
Katie - And could they see that manifest itself in the brain activity then?
Duncan - Yes, so in terms of the brain activity, activity in the nucleus accumbens predicted the next day stock prices. So the nucleus accumbens is part of what's called the basal forebrain, just next to the hypothalamus, a part really quite low down in the brain. And that would predict the next day's stock prices. Whereas the anterior insula appeared to be particularly good at tracking drops in value following a rise, so called inflexions. So the nucleus accumbens appears to make a quite general prediction about the future, whereas the anterior insula, this part of the frontal lobe, seems to be really good at tracking the moment which stock is called reached its peak and it's about to turn into a decrease.
Katie - Do you think it would be sensible to apply those situations beyond just the stock market? Because I can imagine in everyday life you're trying to predict generally the pattern of something. But then if something really important is going to happen, maybe that would be a slightly different question.
Duncan - Really, we need to step back from the whole stock market scenario, because that's just really a game they've created to create a kind of dynamic kind of competitive environment where people are trying to make predictions about what happens next.
In reality, you and I are making predictions about the future all the time - do I cross the road at this point? Do I buy a house for this amount? And interestingly, the areas that are implicated in this study have been associated with those who make particularly risky choices, or who are particularly risk averse.
For example, the nucleus accumbens has previously been assisted with positive arousal and risk seeking choices. And the anterior insular has been associated with general or negative arousal and risk averse choices. So these areas of the brain - they're not the “stock market bits of your brain”, they’re the parts of your brain that track important statistics about the environment around you that we think then you use to make good decisions.
Katie - Oh, I see. Did the particular scientists in this study though, did they look and see out of the participants who was a bit more cautious, and who was a bit more carefree? Because I guess you could probably see that in the variations of the brain activity, right?
Duncan - Yeah, you should be, but my sense is that what you would need is quite a large sample size. So they only have 30 to 40 participants per experiment, and so in order to pull out these individual differences in risk taking, you might need larger numbers. Another really interesting thing to explore would be to compare people of different ages, so there's some evidence in the literature that adolescents, for example, are more prone to making risky choices, especially when it's in collective contexts. So when there are other people around. And so it might be interesting to explore whether there are age related changes in the relative weighting that people place on these different sources of information about what's going to happen next.
Katie - Having said that this needs to be taken beyond the context of just the stock market, do you think if you work on the stock market, could tracking what the brain is doing in this way give you any advantage? Or are you just delving deeper into what the brain is actually already doing?
Duncan - I think it’s that you’re delving deeper into what the brain is already doing. So we know that if you practise tasks everyday then you can really tune performance. So the classic example is London cab drivers. Systems of spatial navigation are enhanced in London cab drivers. Now of course you and I even though we're not cab drivers still have good spatial navigation skills and we’re using the same systems.
Katie - Erm….
Duncan - But they are so well tuned in those individuals. And I can imagine that if you were to recruit some stockbrokers, then you would soon find that they are somehow able to tune into these signals - whether consciously aware of it or not - these signals about what's about to happen next.
17:60 - Mind Shift: how did our brain come to be?
Mind Shift: how did our brain come to be?
John Parrington, Oxford University
Katie Haylor reflects on the elusive and mysterious subject of the “mind” with pharmacologist John Parrington from Oxford University, who has recently written a book all about the topic, called Mind Shift. First up, Katie asked, what actually is the "mind"?
John - We know on the one hand, there's the brain. And then on the other hand there's the individual mind, individual consciousness. And it's been trying to pull these two things together that has plagued people over the centuries, really. And I'm trying to bring these two things together. So on the one hand, yeah, the brain is this physical entity, 1.5 kilograms. It's got the consistency of porridge apparently. On the [other] hand, we've got this amazing kind of individual consciousness and also a social kind of consciousness between human beings, that seems to transcend really the idea of it being just this physical object. So it's trying to pull these two things together.
Now to some extent over the last few centuries, there's been an undermining of this idea that humans are special. So for instance, Copernicus showed that the earth is just another planet. It goes around the sun. Darwin showed that we are connected to all of the life forms on the planet by evolution. But I think it's also important - while acknowledging that we do have this massive amount in common with other species - to recognise what makes us very different. I mean, the fact we're talking through a computer, we are talking over the internet. This is just one of many technologies that distinguish human beings from other animals. And I wanted to explain what is the consciousness that has created these amazing technologies. What makes us different in that sense.
Katie - So what do you reckon does make us unique then? What sets humans apart in terms of the mind?
John - Well, I think it all goes back to how we evolved from apes. And I draw inspiration from things that Darwin said. But surprisingly, a thinker who is not often associated with science, Friedrich Engels - who was Karl Marx's colleague and political activist, friend. He was the first person to recognise that human beings started to diverge from apes when we started walking on two legs. Then this freed the hands to allow us to use tools. Tool use, social cooperation, using tools to transform the world, became a key part of what it means to be human. And this then led to the need to communicate. So that then led to language. And both of these two things - transforming the world around us with tools, but also language - then led to the development of the brain.
Katie - But the thing is, other animals have been documented using tools to a certain extent and communicating between, you know, individuals. So what really sets humans apart?
John - That's a very good point. I mean, it's absolutely true that there are other animals that use tools, not just other primates. Crows are quite sophisticated in this sense. I think what's very different about human beings is the way that we use tools as such a systematic part of our lives and also how we keep on creating new technologies with each new generation. So we can see how in 40,000 years, we've gone from scratching a living from the earth to sending rockets to Mars. And I think that's the big difference between us and other species.
Katie - So how does this uniqueness relate to the mind? You mentioned consciousness earlier. Is this a big part of the argument?
John - Well, what I did in the book was to very much take inspiration from a psychologist Lev Vygotsky who worked in Russia in the years after the Russian revolution, in the twenties and early thirties. He basically took Engels' argument that tools allowed us to transform the world around us, but had also led to the development of the human brain. And said, well imagine that words are also a kind of a tool, but in this case a tool that re-fashions the human brain from the inside. And taking that basic idea, he then developed some very sophisticated ideas about the human mind and what makes it different from other species. So what I've tried to do in Mind Shift is to take Vygotsky's basic idea, inspiration about how words transform the human brain, both evolutionarily and also, you know, as we grow up as children and then into adults. And then say, well how can we use this idea, but then connect it to the findings of modern neuroscience and modern psychology?
Katie - Would you be able to lay out your argument for what the mind shift was?
John - Yes. I mean on the one hand, the human brain has definitely grown in size relative to that of other primate species. So there's been a fantastical growth just in the very size of the brain. And that's reflected also in structural changes. But I argue in the book that it's about far more than size, and it's also about a complete restructuring of the brain. And also the interactions between different parts of the brain. So I show, for instance, in thinking about imagination and creativity, there seems to be a new role for a part of the brain called the cerebellum, which was unsuspected only a few years ago, but it seems to be showing how the human brain has really been radically transformed, both structurally and functionally.
Katie - In reading some of your book, I think what you're saying in your argument is that you've got tools and language or words as being a tool, facilitates the idea of conscious awareness in that if you can articulate either internally or externally your thoughts, then you can make a world, even if that's an imaginary one. And then that facilitates a whole bunch of rich aspects of culture.
John - Very much so in the sense that thought is based on language. So we have this thing called inner speech and actually there's different levels of inner speech. So when I try and articulate my thoughts, to some extent I'm drawing on this kind of inner speech. But I think there's a much more fluid speech going on there when we think that's actually quite hard to explain exactly how that would sound. So that's on the one hand, language is a kind of key part of all this. But I also believe there are fundamental biological differences that also have changed within the human brain. So that explains why there's not really been any real success in teaching chimpanzees to talk in the kind of way we mean talking - in terms of language, using concepts. None of that's really been shown to be possible with any of the species besides us. So although we use language and we can teach words to chimps for instance, the actual human consciousness based on human language is also based on biological differences in the brain, I believe.
Katie - What evidence do you have to put forward that other animals don't have this sort of inner voice or conscious awareness?
John - Well, that's a really good point, obviously. And the big difficulty is that we can't ask, you know, our cat or dog other the species, what they're actually thinking. They can't express themselves through language. I think we really have to see it in terms of the way that we affect the world around us. So I said before about chimps, there's nothing to suggest that the way they interact with the environment has really changed over millions of years. Apart from in a very gradual way, as happens with all biological evolutionary processes. Whereas with human beings, we've seen this dramatic transformation in the way we interact the world, you know, the fact we have electricity now and modern medicine and we're sending rockets to Mars and even beyond.
Of course, there's a negative side to this, and I talk about this in the book as well, which is that we are also destroying the environment. So this isn't all good. It can be very destructive. But it's definitely a major difference between us and other species, our ability to transform the world around us through technology.
Katie - Can we come back to some of the nitty-gritty brain stuff you mentioned before? Could you give us some examples of how you think that being social, developing language, using tools, change the brain on a cellular and structural level?
John - Yes I think that's a really important point actually. And of course one of the problems we face here is that there are - I believe there are important differences and we can see signs of these. For instance, if we look at the expression of certain genes linked to cell signaling in the brain, there are some quite fundamental differences there. There are apparently important differences between the connections between different parts of the brain. And I think this is just this kind of information is just starting to really take shape.
That was one of the reasons that inspired me to write the book was I could see a sign that the incredible technology we have now, whether it's imaging technologies or molecular and cellular analysis, are allowing us to identify major differences between the human brain and that of other species.
Katie - Could you give us a little bit more about which ones you draw attention to?
John - One thing that struck me was dopamine. It's one of the neurotransmitters in the brain. It's the classical neurotransmitter involved in reward, for instance. And I found it interesting that one of the genes that is involved in the production of dopamine was found to be expressed in some areas of the brain that are linked to more, what we call higher functions - imagination, creativity. And there didn't seem to be the same expression in, say, a Chimp. So that was an indication that there are, even at the most basic level of neurotransmitter action, there are potentially some quite important differences. The cerebellum is another important part of the brain I looked at. Up till now, until recently, the cerebellum was thought to be really just involved in repetitive movements. If you learn to play the piano or to ride a bike, or to throw a ball into a hoop, that that's all been known for some time to be related to the work of the cerebellum, which is this little part of the brain that sits in the back of the brain.
But what we're starting to realise is that things like imagination, creativity that were thought to always be part of more a function of the kind of frontal structures in the brain, also seem to involve the cerebellum in some quite important ways. And there's also evidence that the interaction between the front parts of the brain and the cerebellum are quite different in humans compared to other species. So there's been a transformation there in that sense.
Katie - Can you give me a few more sort of concrete examples?
John - Yeah. I think that's the bit where it comes difficult to connect all of this together in the sense that ... well, first of all language itself, it's not just communication. It's about a radical new way of looking at the world. It allows us to conceptualise about the world. It allows us to see past, present and future. Somehow or other that must have transformed our basic, you know, mental process. And I go through different ways in the book of how that state transformed imagination, creativity, even our emotions, practically any human emotion is affected by this role that language plays in the brain.
Now connecting that to actual brain structure, individual neurons, is the more complicated bit. I do go through some very interesting studies that have looked at how individual neurons seem to register memories. How they seem to be involved in connecting different things in the world together. So there are some glimmers of understanding there. But it's very much the kind of the first step really of trying to understand how language itself transforms the brain in the ways I'm talking about.
Katie - Okay. So you gave us an example of dopamine. And I think what you're saying is that genetic expression, when it comes to neurotransmission, there's evidence that that varies between different species, but also these structural differences that you mentioned.
John - I think there's another aspect as well that I didn't mention, which is that I've been very inspired by some of the work of Earl Miller who works at MIT in Boston, USA. And he's come up with some very interesting ideas recently about the way that brain waves of different frequencies can regulate interactions between different parts of the brain. So based on this, and then thinking about my thesis that human brain is quite different in its structure and function from other species, I postulate that this coordination between different parts of the brain that I see as being quite different in human beings, is potentially being regulated by these frequencies, different frequency brainwaves.
Now that's not to say that brain waves of different frequencies don't regulate what happens in an animal brain. I can imagine that if you have a pet cat who suddenly sees you or spots a mouse or whatever, there may be this dynamic change going on between parts of the brain. What I'm speculating about in the book is that language may completely transform the way these brainwaves regulate brain function. I mean, of course it's difficult in some ways to prove all of this. This is very much a hypothesis. And in fact in the book I, towards the end of the book, I go through a number of ways we might start to test this as an idea.
Katie - I see. So it's a work in progress, this idea.
John - It is definitely a work in progress because I think it would be amazing if a single book could explain consciousness. And that certainly wasn't what I was expecting to achieve! What I hope I do in the book is to raise this is a very provocative idea that there is this radical difference between human brains and those of other species. And I think this has research implications because although as a research scientist myself, I'm completely of the idea that we can learn fast amounts from studying other species - mice, but also controversially, primates - I do think there are, if there are these fundamental differences between human brains and those of the species, it does say there's a limitation to what we can learn from those studies alone. And maybe we have to be more creative about the ways we use opportunities to learn more about how the human brain works. You know, there are some non-invasive ways - imaging, different kinds of imaging techniques, are allowing us to probe the human brain in all sorts of ways. There are opportunities to even make recordings of a human brain while people are undergoing surgery, say for epilepsy treatment. So there are possibilities, but none of this is necessarily that easy. I guess one thing I'm saying in my book is that we need to take more seriously the idea that human studies need to compliment animal studies, if we are truly to understand what makes human consciousness unique.
Katie - The thing is the brain is just so incredibly complex. And there's so much that we don't understand about what's contained within our skulls. Do you think there's a possibility that actually other species are equally complex, equally fascinating in the way that their brains work. It's just, it could be quite different to humans?
John - Absolutely in the sense that I don't think we can ever underestimate just how complex the brain is say of a primate, for instance, or even a mouse for that matter, or even a fruit fly. I mean, one of the reasons I'm skeptical about the potential for so-called artificial intelligence to overtake human intelligence - this idea that computers might soon be able to think like a human being or maybe even surpass our kind of thinking - is that I think we often do estimate the complexity at the molecular and cellular level that we have within our brains. But also those of other species. So that's one thing to say.
But I do think that the way that language has transformed the brain, both in the way our brains have then evolved through that interaction via language with other human beings, but also the way that we grow up within a human society and that radically transforms our brains. Because learning has this incredibly important role to play in human culture, I think. Far more in a sense than it does in those of other species. All this I believe has led the human brain to be a different level of complexity compared to brains of other species.