Emily Bates
Welcome back to the Nature Podcast, this week: giant jets from a black hole…
Benjamin Thompson
...a the single-step process for making metal alloys … I’m Benjamin Thompson.
Emily Bates
And I'm Emily Bates.
First up, we’ve got big news. And when I say big, I mean it because astronomers have spotted the largest black-hole jet ever detected and it. Is. Massive. Black holes are often thought of in terms of sucking things in, but in some cases they also fling stuff out as well. When this happens matter gets ionised and fired out from the top and bottom of the black holes. These violent and powerful phenomena are known as black hole jets. The biggest of these are made by supermassive black holes and can be up to several million light years in size. And now a team has seen the biggest yet. It’s around 7 megaparsecs, or 23 million light years, in size. To put that another way, if you take the Milky Way as being 100,000 light years across then that's like 233 milky way galaxies stacked on top of each other end to end. That is a full six and a half million light years bigger than the maximum size astronomers theorised these jets to be. Reporter Nick Petrić Howe caught up with one of the astronomers behind the discovery, Martijn Oei, to find out what this is telling researchers about the early Universe. He started by asking him to explain a bit more about these powerful jets.
Martijn Oei
So in the center of every galaxy, you have a black hole that creates material, and that material consists out of nearby gas, sometimes bigger objects, like stars and dust. And when that material comes close to the black hole, most of the material actually falls into the black hole, but a part of the material is being ejected outwards, and that material actually falls apart into elementary particles, electrons and positrons, in an interplay with light from the accretion disk, it’s accelerated and goes into two beams of energy, basically that emerge along the north pole and south pole of the black holes’ rotation.
Nick Petrić Howe
And these are like incredibly violent processes that are flinging this matter out into the universe, right?
Martijn Oei
Right, yeah. These are hugely powerful things. So they influence the evolution of their entire galaxy. The particles go with almost the speed of light, and they have very likely an effect on the surrounding intergalactic medium as well.
Nick Petrić Howe
And so what do these things do in terms of galaxy formation?
Martijn Oei
So to form new stars, you need to have the interstellar medium be relatively cold and relatively dense. And as the black hole launches jets, the jets sort of move across, move through the interstellar medium, and they heat the medium, and they also dilute it and sort of spread it part. So in that way, the jets inhibit the formation of new stars and makes the Galaxy evolve much more slowly.
Nick Petrić Howe
As I understand it as well, for the past 50 years or so, all the sort of observations of these black hole jets they’ve been like a certain size, right?
Martijn Oei
Right, yeah. So when those black holes launch jets, those jets are, from a theoretical point of view, as far as we understand the physics, they are quite unstable. So they're very light, and they move through a much denser interstellar medium. And there are some kind of hydrodynamical instabilities that arise as a result of that, and that tends to create turbulent motions that destabilize the high-speed jet. And the other effect is when a low-density medium tries to push through a high-density one. And that's familiar, for example, in those mushroom clouds, when you have a very big bomb, then you have also, like a low-density medium that tries to find a way through the air. And all these kind of effects try to destroy the jets. So most of the jets are actually pretty small before they break down. So from a theoretical perspective, it is kind of surprising that they can actually grow to the scale of their entire galaxy and sometimes reach beyond that. Sometimes jets can really reach a sort of cosmological length. So astronomers measure things that are cosmological with a unit called the megaparsec, which is 2 million light years. The largest one reached up until about five megaparsecs.
Nick Petrić Howe
Well limits, I guess, are made to be broken, because looking at your paper, it seems that you've spotted one that's even bigger than that.
Martijn Oei
Yeah, that's right. So the main discovery of the paper is that we found this very long pair of jets that is about seven megaparsecs long. So that is a significant increase in the absolute size. But what, in my view, makes it more spectacular is that this jet system also occurs relatively far back into the universe's history, so about halfway along its current age, and back then the universe was also smaller. So that means that a relative size of the jets is very big. So this jet pair spans a third of a cosmic voids, which are sort of the largest empty spaces that we know of. And also, this black-hole jet pair comes from a type of active black hole that was really common in the early few billion years of the Universe existence. So it suggests that these type of very-long black-hole jets at early epochs might be more common.
Nick Petrić Howe
And so you mentioned earlier that there's all these instabilities that were thought to maybe constrain these jets. Does this imply that maybe there was a difference in this earlier epoch in the universe? Or to me, it would sound like it would be harder, like the Universe was smaller but more dense, like, surely it'll be harder to push a jet through. So what is it that is maybe allowing this jet to be that big?
Martijn Oei
Yeah, so back into the past, at least the average density in the universe was higher. During the growth time of this jet pair, the mean density of Universe was about 7 to 15 times denser than it is now, so roughly an order of magnitude. But what could help the jets grow is actually the large-scale structure of the Universe. Those were slightly less formed at that time, galaxies themselves were slightly less massive, and there was more fuel that was available to the supermassive black holes. So it could be that the jets themselves were more powerful.
Nick Petrić Howe
So I guess for this jet to push so far through this denser medium, it must have been something pretty powerful, right?
Martijn Oei
Yeah, it's very powerful. So if you try to do some sort of simulations to see how powerful these jets must have been, and after how much time they must have been going on, you find that the power is basically more than many galaxies produced combined. So all the stars in any galaxy, all the light that they produce, that is a hundred of those galaxies or so are combined as this jet.
Nick Petrić Howe
Wow.
Martijn Oei
And then it's been active for a billion years or so, according to the best models. And if you multiply the power with the time that the jets have been on, you get a huge amount of energy comparable to what happens when galaxy clusters merge. That is often considered by astronomers, the most powerful type of events that has happened after the Big Bang. But apparently these jets can sort of rival that amount of energy output.
Nick Petrić Howe
That's amazing. And also, we've kept referring to this as ‘a jet’, or ‘the jets’, but you did actually name it, right? Was it you who named it? Or one of your colleagues?
Martijn Oei
Yeah, so I was doing the search for the manual search of these jets with the students, and so we were trying to think of good names. And then we dove into Greek mythology, where there's a very famous mythological story of the Gigantomachy in which the Giants, so the offspring of Gaia, rebel against Olympian gods, and they– they fight with them for control over the Universe, basically. And in this story, those Giants are basically, they're the bad guys, so things are not really usually named after them. And so we checked whether those names already existed in NASA databases that name asteroids or minor planets, and we found out that they were not in use. So we called this particular jet system Porphyrion, after one of those mightiest Giants of Greek mythology.
Nick Petrić Howe
That's super cool. I really enjoyed that. And so what does this discovery mean for our understanding of the Universe?
Martijn Oei
Right. So I think one of the more interesting messages is that you can create multi-megaparsec scale jets already at the time when the Universe was much denser from ancient type of black hole that was more common back then. And additionally, because they could really reach the scale of the cosmic void, it means that no place in the Universe is, in principle, safe from activity of black holes. And in particular, these jets carry magnetic fields. And what I think is these black hole jets, they can spread magnetic fields through the cosmos as well. And people try to understand how the magnetic fields in the Universe came to be, and some people invoke very exotic new physics for that. But I think that without introducing new physics, and just by seeing that black hole jets have a big reach, it might be possible to explain that as well. So I think it could trigger some more interest in how magnetic fields came to be. That's a topic called magnetogenesis. It's quite a cool name I think.
Emily Bates
That was Martijn Oei from Caltech in the US. For more on that story, check out the show notes for some links.
Benjamin Thompson
Coming up, a one-step approach to making metal alloys, that could drastically lower emissions. Right now, it’s the Research Highlights, with Dan Fox.
Dan Fox
Engineers have created new micro-resolution knitted fabrics that can protect a wearer from mosquito bites. Clothing offers a simple way to avoid insect bites, which every year contribute to more than 700,000 deaths from disease worldwide. But most outfits do little to block mosquitoes. So in an attempt to tackle this, researchers designed several fabrics and tested their resistance to the blood-sucking insects by placing a sleeved human's arm inside a cage of mosquitoes. Taking microscope images of the fabric and counting the number of bites revealed that certain knit patterns boosted protection, especially when combined with thicker threads, more spandex content and smaller stitch lengths. Putting fabric through a hot, wash and dry cycle also reduced bites by shrinking the gaps in the knitted pattern. The blocking materials proved just as breathable as a control material made of spandex polyester blends, but wearers found the engineered fabrics to be slightly less comfortable. The authors of the paper say that future research will improve the comfort of the bite-blocking knits and that these materials could also be used selectively to cover only body parts that are particularly enticing to mosquitoes. Got an itch to read that research, it's published in Communications Engineering.
Analysis of nearly 1,200 languages shows that islands play a crucial part in fostering language diversity. The effects of islands on biodiversity has long been studied, and previous research suggests that language diversity follows similar global patterns. Researchers analysed the database of global languages and found that 10% of the world's languages are ‘island endemics’ — spoken only or mostly on islands — even though islands make up less than 1% of the world's inhabited area. The more isolated the island, the more likely it is to host endemic languages. With large, high-elevation tropical islands, such as some of those of Papua New Guinea more likely to have more endemic languages. And while this work shows that island languages are not more endangered than mainland languages, they remain important arks for maintaining language diversity. If that research is speaking your language, you can read it in full, in Nature Ecology and Evolution.
Benjamin Thompson
Metal alloys have played an enduring role in the shaping of the world. Around five thousand years ago, the Bronze Age saw humans blend copper and other metals to make a material that was harder and more durable than those that went before. Skip forward to the present day, and a wealth of different alloys have been created — they're found everywhere, from computing to construction, but their creation comes with significant environmental costs. Making metal alloys is typically a multistage process — the fundamentals of which aren’t that different from the Bronze Age. First, minerals need to be mined, and the metal oxides they contain must be stripped of their oxygen to make pure metals — a process known as reducing the metal oxide, which is often done in giant furnaces driven by carbon fuels. This needs to be done individually for each metal that makes up the alloy — it's only once they're purified that they can be mixed together. Finally, a stage known as thermomechanical processing adjusts the alloy to give it specific properties. These stages often happen in different facilities and produce a lot of emissions, many of which are related to the use of carbon to strip metal oxides of oxygen. Some steps are being made to lower these emissions, recycling of discarded metal, of course, being one of them, but also things like using hydrogen to reduce metal oxides, creating H2O rather than CO2. This week in Nature, a team demonstrate in the lab a way to make alloys that they think could lead to even lower emissions and their approach is rather different. Rather than a multistage process, theirs combines everything into a single step, from oxide to alloy. To find out how it works, I spoke to one of the authors Dierk Raabe from the Max Planck Institute for Sustainable Materials in Germany. He explained how the idea came about.
Dierk Raabe
So we were originally really motivated by just making the total manufacturing more sustainable in terms of avoiding the use of carbon and replacing it by hydrogen as a reductant. But then we suddenly realize, when you start using some of these minerals, they are mixed rocks. That means they already contain certain elements, and we. realised, why do we do this in a classical way that we extract metal by metal, and, you know, produce 80 different metals and then mix them after we extract them, say, can we not exploit that heat in the reactor that we need for the reduction anyway, and directly blend the oxides in an appropriate way to arrive at the chemistry the way you want it. So we merge the metal production with the metal mixing. And when we have that done, we realized, you know, yeah, we have a block of the right chemistry, but then you have to give it to a blacksmith and forge it, roll it and heat it, beat it, and do all these things, lend the material its properties. But then we realize some of that can be also done in the same reactor by adjusting the temperature, the time, that the atoms diffuse and do their job. And so we suddenly have all the three steps in one reactor.
Benjamin Thompson
So hydrogen is at the centre of this but can you give me a sense of how this process works?
Dierk Raabe
The idea is based on the interplay of adequate mixing of the minerals, of the oxides that carry certain elements you want in the final alloy. And the second big player is the reductant in itself, which used to be carbon, and now we switch to using hydrogen or other reductants. And that means we must thermodynamically learn and understand which types of oxides you can mix with which type of reductant to say, does the energetics go in the right direction to extract the oxygen and leave you with the metal you want? And considering also whether some of these atoms from the reductant might enter into the alloy and so on. So suddenly this reductant becomes also your partner in the game, and that, you know, must be calculated to see, is it a self-driven process, or do I have to add additional heat and so on? Is it happening, or is it not happening?
Benjamin Thompson
And in terms of what goes into the reactor, then, is it just a block of rock containing different oxides? What does it look like for someone who hasn't seen it in action?
Dierk Raabe
Yeah, in this case, we kept it comparably simple to make the point, and used iron oxide and nickel oxide. The iron oxide is so called ‘iron sand’. Sometimes, when you see black sand at beaches in certain countries, then this is often magnetite mineral. So it's just magnetic iron oxide which is used in steel manufacturing. So it can use that powder from a beach directly to make this alloy. The nickel oxide, the second player, we had to add from an oxide, because we currently work on using the original rock directly. But there the nickel is rather dilute, so we had already enriched nickel oxide. But yes, indeed, you have, in principle, a powder of dirt in your hand, put it in reactor.
Benjamin Thompson
And this alloy you've been looking to make then is called invar. So this is an alloy of iron and nickel, and it seems to be, maybe not the most well-known alloy, but certainly one of the most widely used.
Dierk Raabe
Yeah, the invar alloy carries this funny name from the invariability it has, and that relates to its relatively constant thermal length expansion. Typically metals have that feature, like other materials too, when you make them cool, they shrink a little bit. When you make it hot, they expand a little bit. We need it today a lot for fine gadgets, also for transport of super-cold liquid gas, which has gained momentum on the globe. So we thought that is a great target, because it is well known. It can be produced today, but with a very, very high carbon footprint. So we thought that is something where it's really worth making it more cleaner, and we use it as a blueprint material.
Benjamin Thompson
And so let's talk about what you actually made then. So you had your mixture of oxides, you put them into your lab reactor, heat it up, control the temperature, add the hydrogen gas in to reduce these oxides to the metals. And this one stop process, what comes out the other end?
Dierk Raabe
Yeah, what comes out at the other end was, in principle, a little bulk type of material that we in the third step that we integrated also shaped, in a way, through the adjustment of temperature and time that led to a certain, you know, compactness. Because otherwise, when you just put powder together and reduce them, like we did, it would maybe happen that you have little, you know, spheres baked together, but you have a lot of porosity between them, and that might make them brittle, or you lose, you know, volume and stuff. And so we wanted to make sure that the diffusion along the surface of these little grains also fills all these pores, so that you really have a compact piece of alloy in your hand, as if you would go to a shop and buy this.
Benjamin Thompson
And in terms of the chemistry, what did you see using this method?
Dierk Raabe
What was unexpected is that it was not like, okay, first, thermodynamically if the nickel is reacting with the hydrogen, and the nickel is produced, and then the hydrogen picks the iron oxide and makes pure iron, and these diffuse together and so on. But what we discovered that first, indeed, you form very tiny nano droplets of nickel, and then in the iron oxide, it's already starting to jump over into this piece of nickel. So we also discover quite new principles, how you mix them and all.
Benjamin Thompson
And this invar you produce, then, how does it compare to invar that's made using conventional manufacturing techniques? Using furnaces and what have you?
Dierk Raabe
So we compared it to standard produced material, and in many respects, they're absolutely comparable in some respects they turned out to be even better.
Benjamin Thompson
And what about the yield? How does that compare?
Dierk Raabe
The metallic yield, that means how much metal do I get back from the oxide I put in? I guess is relatively comparable, because it's the same for blast furnace. Little bit get out what you put in, when you put it to the blast furnace, very high-quality mineral, iron oxide, you can reduce, maybe, like 90-95% of that material and extract the metal from it. So I think in terms of the yield, the thermodynamic limits are kind of comparable. It's not so much the machine, but the thermodynamics of the process.
Benjamin Thompson
It does have to be said, though, that I think when people think of the word ingot, they might think of like a gold bar, I guess something quite large. But in this case, what you produced is not that, what you've made is smaller than a coin. And there's often a gap between a lab result and day-to-day manufacturing–
Dierk Raabe
–yep–
Benjamin Thompson
–because at the moment, you are working at a lab-scale setting. Do you think this could be scaled up?
Dierk Raabe
I think it can be done because that type of reduction principle with hydrogen is very nicely scalable because you essentially expose an oxide, or in our case, an oxide mixture, to a gas atmosphere consisting of some percentage of hydrogen. And that can be scaled up to bigger furnaces, which already today exist, they just don't integrate this idea of pre-mixing the oxides in that. So, yes, you can produce bigger blocks. However, we must also see that there are many, many metal alloys that are used in comparably smaller functions and which have very huge carbon-footprint from catalysis through alloys that you need in a microchip or in a laptop, in a mobile phone, or in biomedical implants and so on, where the target quantities are anyway, not so gigantic, and that scalability is very easy to do.
Benjamin Thompson
And have you done any calculations as to how this process could compare in terms of emissions to regular manufacturing if it is scaled up?
Dierk Raabe
Yeah, that's a very essential question, and it is indeed up to 20-30% more sustainable than the existing processes. But one must build in into these calculations that it depends, for instance, on the source of your hydrogen. Was it really made by sustainable electrolysis process, or is it like mostly today done by methane reforming, which in itself has a high carbon-footprint? So that means you have a huge error bar on that. But say however dirty, say your grid carbon-footprint is, or the production of the hydrogen is and so on, you will always do better than conventional manufacturing, because the sheer fact that we do everything in modern furnace makes it economically and ecologically much, much better than established techniques.
Benjamin Thompson
And one thing that struck me about this work is that you've shown evidence that you can take this multi-step process to make an alloy and reduce it to a one-stop shop. Why do you think no one's tried this before? I mean, chemists have been working with metals and alloys for a very, very long time. Why has no one considered this an option before do you think?
Dierk Raabe
So I think in principle, that has been done before, maybe without knowing or without planning it. We have often, in history of metallurgy, already oxides that were pre-blended, because that's what you inherit from the mining sector. Nowadays you would separate into the zinc industry, the tin industry, the copper industry, and later buy that and mix it again. I say we must go back and directly design the alloy that we want from the pre-mixture only from the most dirty available and oxidized feedstock that we can get. And I think in history, that happened quite often, but without that thermodynamic planning of saying, I direct the entire process in one furnace, only adjusted to the target alloy, and that, I think, is a pretty new idea.
Benjamin Thompson
Yeah. So you've shown your evidence that this works, but presumably it's not ready to go yet. Like when people look at this paper and say, oh, wow, that seems fantastic, usually there's more to it than that, right? What science questions remain to be answered?
Dierk Raabe
That's a very fair question. I fully agree that it's not ready to be unleashed to a bigger market. We must understand that the bond between the metals and the oxygen has very different strength. That means some metals are very hard to extract from the oxygen, like, for instance, aluminium, and that simply might not work by this technique, because your hydrogen is too weak to take the oxygen out. That means we must better understand what type of reductants and methods we use to realize it also for those metals. And the second big challenge is we want to get as close as we can to the actual rocks, to the minerals that you find in the mine without much preprocessing, making this as lean as we can. However, some of these oxides are pretty mixed. That means you sometimes have four or five or six other elements in the rock that you might not want. How to eliminate this, how you kick them out of the actual alloy? That's also a barrier that is unsolved for many variants.
Benjamin Thompson
Dierk Raabe from the Max Planck Institute for Sustainable Materials there. To take a look at his paper, head over to the show notes for a link.
Emily Bates
Finally on the show, it’s time for the Briefing Chat, where we discuss a couple of articles that have been highlighted in the Nature Briefing. Ben what have you been reading?
Benjamin Thompson
Yeah I’ve got a story that I read about in Nature, and it's about using AI to redraw the virus family tree. Now this is based on a paper in Nature, and what's interesting is that it sort of went about it in a slightly different way.
Emily Bates
So what do we know already about that family tree?
Benjamin Thompson
Well, the way that this kind of tree is put together, so the story of viral evolution is based on genome comparisons, okay. How does this compare to that? These compare to those you know, that sort of thing to make up a family tree looking at differences in the genomes. Now, this can actually be quite a tough thing to do for viruses, because they can evolve really very quickly. If you think about viruses with an RNA-based genome, they don't necessarily correct any errors that creep into their genome, so they can change very quickly. And viruses, in general, can acquire genetic material from other organisms. And altogether, this means that using the genetic sequences can actually make it difficult to find any deep and distant relationships between viruses. But as I say, they've gone about this in a slightly different way, and they've looked at proteins instead.
Emily Bates
So what's the difference of looking at the proteins as opposed to the viral genome?
Benjamin Thompson
Yeah, that's a good question, and the shapes, or the structures, of proteins that are encoded by viral genes, now these tend to change more slowly, okay, so they can be used to kind of tease out any hidden evolutionary connections. But this has been a tricky thing to accomplish, because making protein structures at scale has been historically tough, and this is where the AI aspect comes in, okay. So in this work, they've used new prediction tools like AlphaFold from DeepMind, and in this work, they've used it on a group of viruses called flaviviruses, and this group contains the hepatitis C virus, the dengue virus, Zika viruses, and a bunch of others that are major animal pathogens that have the potential to be threats to human health. And in this family, then, of these flaviviruses, much of the research on the evolution has been based on sequences of slowly evolving enzymes that copy the viruses’ genetic material. But little is known about the origins of what's called viral entry proteins. Okay, now, these are important proteins that flaviviruses use to get into cells, right,so the entry protein, as the name suggests. And this determines what sort of hosts they can infect and that sort of thing. And one of the researchers behind this work argues that not knowing much about these viral entry proteins has potentially slowed the development of vaccines against things like hep C, which, you know, kills hundreds of thousands of people a year.
Emily Bates
So they've used the AI to look at a bunch of these proteins and compare them and see how they're all connected?
Benjamin Thompson
Yeah, that's basically it. And so the team used DeepMind’s AlphaFold2 and Meta’s ESMFold to generate over 33,000 predicted structures from 458 flavivirus species okay, and say the AI allows them to do this at scale. And these predicted structures — and it has to be said they are predicted — allows the authors to identify viral entry proteins with very different sequences to known flaviviruses. So they can really do some comparisons there, and they found some quite unexpected things. It turns out that a subset of viruses, including hepatitis C, infect cells using a system similar to one discovered in what are known as pestiviruses. And these include things like classical swine fever virus, which, as its name suggests, causes, you know, a very nasty disease in pigs. And, you know, the AI enabled comparisons showed that this system is quite distinct from many other flaviviruses. A bit of a mystery where it evolved from, but it showed other stuff as well. Zika virus is very well studied, and the entry proteins have been well studied. And in this article, the researchers say that these proteins have some similarities to what they describe as, “weird and wonderful”, flaviviruses, including Haseki tick virus, which can cause fever in humans. And strangely, some flaviviruses seem to have an enzyme that looks like it's come from a bacterium. Now, this has been shown before, but it seems like genetic piracy has played a big role in the evolution of these viruses.
Emily Bates
So this is a theft? The viruses have come in and taken that from bacteria somehow.
Benjamin Thompson
Yeah, that's one of the reasons it has been so difficult, I guess, to figure out where all these family trees are, because viruses often incorporate bits of genomes from the organisms they infect. But I think what's interesting about this is that it shows that this is an approach that can be done, right. As I say, it's been difficult to make a huge amount of these predicted protein structures, and it seems like the flavivirus work is kind of the tip of the iceberg. Of course, the number of viruses and viral species is enormous, and the tree of life that they are attached to has got many, many branches and twigs and what have you to kind of stretch that metaphor to breaking point. And so being able to try to trace these is interesting from an academic sense, but also potentially from a public-health sense as well as I say, knowing more about these entry proteins could potentially help in vaccine production.
Emily Bates
Right. Interesting that AI can be used to look back in evolutionary time and work out how this complex network of species came to be. And moving on to something slightly different, Ben, have you ever been in a high-stakes situation where you needed to do well and it just all went completely dreadfully?
Benjamin Thompson
Right. I'm suddenly transported back to youth football, youth soccer, and me missing some vital penalty — I'm sure everyone being really disappointed. But I must confess I wasn't entirely expecting this to turn into the Ben therapy hour. Okay, what's this to do with?
Emily Bates
Well, it seems that choking under pressure is linked to a particular drop in activities in the neurons in your brain that prepare for movement. And this came from a paper in Neuron that I was reading about on nature.com, and also, the phenomena doesn't seem to be unique to humans. So the same way you may have missed a crucial match-winning penalty, monkeys can also underperform in high-reward situations.
Benjamin Thompson
Right, so I'm guessing they're not getting the monkeys to kick a ball about, what does this experiment look like?
Emily Bates
So the team set up a task where rhesus monkeys received a reward after quickly and accurately, importantly, moving a cursor to a target on screen, but importantly, they would know the kind of reward they were going to get. So it's either a small reward, a medium reward, a large reward, or a jackpot–
Benjamin Thompson
–right–
Emily Bates
–and these jackpot rewards were very rare and very big. So this was high stakes, high reward situation for the monkeys. And they had a chip implanted in their motor cortex, and the team could see how activity changed in the different reward scenarios. They found that in the jackpot scenario, the activity of neurons associated with motor preparation decreased. So motor preparation is the brain's way of making calculations about how to complete a movement before you do it.
Benjamin Thompson
So there were differences in how prepared they were depending on the size of the reward.
Emily Bates
Exactly. So when the rewards were small, medium and large, they found that this preparation for the task increased up until this sweet spot around the large task, and the monkeys performed really well. But then on the jackpot, these preparation neurons, the reward was too high, and it dropped off a cliff, and suddenly they started underperforming on the jackpot scenarios.
Benjamin Thompson
Wow. Okay, and obviously we can sort of put ourselves in that position, but monkeys aren't humans. Is this relevant do we think to the situations we find ourselves in?
Emily Bates
Obviously, yeah, it's in monkeys. So this isn't one-for-one correlation, but this sort of high reward, high risk scenario is something that we see in sports and things like that. And it's worth mentioning as well, they were just looking at the motor cortex. So there are other areas of the brain that might be involved, particularly in humans, that might lead to this phenomena. And whether there's a way you can kind of avoid the phenomena they're interested in seeing, whether choking under pressure could be avoided, maybe by getting feedback on your brain activity and sort of saying, oh, you're getting too excited now, calm down.
Benjamin Thompson
So we need neuroscience and time travel then to take me back to that youth-football moment and hope for a better outcome.
Emily Bates
Absolutely, it's the only way.
Benjamin Thompson
Well, an interesting story, and one certainly that I and maybe our listeners will be considering and wondering how our motor cortex is doing when we come up into these high-pressure situations. But let's leave it there for this week's Briefing Chat. And listeners for more on those stories, and for where you can sign up to the Nature Briefing to get more like them delivered directly to your inbox, check out the show notes for some links.
Emily Bates
And as always, you can keep in touch with us on X, we’re @NaturePodcast, or you can send an email to [email protected]. I’m Emily Bates.
Benjamin Thompson
And I'm Benjamin Thompson. See you next time.
