Brendan Walker on designing rollercoasters

Read the full transcript of our Science Focus Podcast interview with Brendan Walker about rollercoasters - listen to the full episode at the bottom of the page.

Published: June 22, 2020 at 6:59 am

Brendan Walker

Well, a thrill engineer, I mean, I came up with the description, because I really liked the idea of the sort of objective practice of engineering which is creating things with, with rules, but also the very subjective elements of human emotions, which is the thrilling aspect. So, in a sort of very headline sense, being a thrill engineer means I really try to craft, human emotional experience and very extreme human emotional experiences, but using design principles.

Amy Barrett

And what kind of psychological levers Are you trying to pull when you design a roller coaster, and which are the most powerful ones of those?

Brendan Walker

Well, when you think of a roller coaster, in fact, if I put you on a roller coaster and blindfolded you, your body's levels of arousal track very, pretty precisely the the changes in acceleration forces which are felt.

Now, arousal is just one half of the picture. If you look in a very simplistic view of human emotions, you can look at two dimensions of pleasure, or valence as the scientists call it, and arousal which is our body's being pumped up and kind of ready for action. So rollercoasters are so successful because they really grab hold of that element of arousal and because it's so tightly interlinked with our physical sensations that we get from the world, that we can almost force an emotional experience by the very shape of the roller coaster.

Amy Barrett

And so, has there been any evidence that going on roller coasters thrill seeking in general, i s it good for you?

Brendan Walker

There's, I mean, I've done some studies. In fact, Thorpe Park looking at well being associated with going on roller coasters. The first thing that they want you to look at was going well, will it help you to lose weight, and I can tell you walking between roller coasters will make you lose more weight than actually being on one.

In fact, I think we found out that being on a roller coaster was equivalent of eating one less chip so physically No. But mental well being, is a really important aspect of what I do. So there's when, if you experience pleasure, there's the other half of the emotional experience in a social context with friends, people you care about, that can be translated into happiness and happiness itself is a very infectious phenomena and it is a real contributor to, to mental well being. So it's all within the, the broader discussion about the importance of play, and social play in society, and that being really pivotal in the mental health, mental well being of the society.

Amy Barrett

But not everyone enjoys rollercoasters, why are some people more say sensation-seeking than others?

Brendan Walker

Well, if you look at the personality I see types of people who tend to go to a theme parks and go on rollercoasters. In fact, I usually quote Marvin Zuckerman who is at Delaware Tech, I think it was the grandfather of thrill seeking.

He looks at personality types in classifies them in four different dimensions. One is thrill and adventure-seeking which is very much to do with roller coasters and that kind of high adrenaline kind of experience.

The other one is experience seekers, people like unusual experiences like theatre and circus and magic.

The other one is disinhibition. So people who might like to scream on a roller coaster really let themselves go. And the other one is susceptibility to boredom, which is a great measure, particulalry if you're going to queue for an hour to get on a roller coaster that lasts only two minutes.

So and then there's another dimension which is our perception of risk, and all of these factors vary throughout our lifetime. They can also vary with other events in our life such as having, having children. They can alter this this sort of psychological profile.

But so we tend to see people who score high and thrill and adventure-seeking and experience-seeking will enjoy roller coasters, but also it says people's perceptions of risk, novelty-seeking, and critically, I think it's how we ride roller coasters.

So that's such a rough kind of way to understand people, but if I went on a ride with you, we might have a great time because we're good friends. If I go on a ride, because I'm doing a very objective, scientific exploration of the ride, I'll have a different experience. If I go on it with somebody I don't like in the rain, I could have a miserable time. So there are so many contributing factors.

Amy Barrett

How do you combat that as someone designing a ride knowing or not knowing the situation that the passengers will find themselves in when they go on it?

Brendan Walker

Yeah, so I think, as I was saying with with rollercoasters and controlling people's levels of arousal, and that being so tightly controlled with their emotional experience, these other elements, so the other ways you can create thrill or emotional experience can come through being valued, which is a very sort of social setting, how you feel about yourself, how you think others are perceiving you.

There's a spectacle, which has to do with magic and amazing things that are happening around you and really question your belief systems. And then there's all sorts of ideas to do with power and control which are very much tied in with with potential energy and kinetic energy.

And so all these factors, there are multiple streams and multiple ways you can actually think about engineering and creating a ride. And it's really flipping between these different modes where you sort of examine the experience.

But I can say you can make the most amazing ride, but unless you're riding with the right person, it means nothing. So I tend to like when people say what's your favourite roller coaster, there's a ride called, well it's a kind of Magic Mouse kind of ride. It's there's one at Alton Towers called Spinball Whizzer, and it's a roller coaster which doesn't invert but the car or sat in, four people can go and it - two pairs back to back - and the orientation of the car spins round and you don't know whether you're going to go forwards, backwards, down slopes, up hills, and it's that element of unpredictability, which, with people, you know, or with strangers, somehow breaks the ice and gives this sense of social cohesion like in any kind of disaster when you don't know something's gonna happen.

And so I think right like that, when they're very carefully, the social dynamics are carefully managed, I think you can then immerse people in the other aspects of the ride. So, yeah, it's certainly I think a lot of these techniques have much more in common with live performance and live theatre than they do with engineering.

Amy Barrett

And so you've been involved from the conception right up until the end, the, the final result is that right?

Brendan Walker

Yes, I have been involved in the design of roller coasters from early inception. So for example, The Wicker Man at Alton Towers, all we knew was they had a footprint of land, and we had an audience who are demanding a new roller coaster. After that, there were no other prescriptions for how or what we would make.

So in a situation like that, there are several things we look at one is what are the cultural trends in society? What novel technologies are out there? What are people talking about? So this is where the idea in that particular instance, where wooden roller coasters came in, because obviously in America, they're very big and very popular, in the UK, we only have one or two, and then this theming to do with The Wicker Man, the horror scenario, kind of started to evolve.

And then there are other rides like 13 at Alton Towers where they, that had been pretty much finalised, but there was one feature on it, which was the vertical drop feature, which, if you don't know 13, you go in and a roller coaster - this isn't a spoiler, by the way, I think most people know this - you go into the dark tunnel, the ride stops, and then it falls. Your carriage falls vertically through the dark.

And they wanted to know for for the 95th percentile, that's for like 95 per cent of their audience who go to Alton Towers, was this going to be thrilling? They wanted to know how far in the dark should we drop people, and there's a there's quite a precise calculation.

We can work out how quickly the brain processes novel information such as dropping in the dark, and how long it takes to translate that into action such as gripping the arms of your chair or screaming or something else.

Say and if you look at psychology experiments in this area, you find the time it takes for 95th percentile, which is about point seven seconds, and then you calculate how far in point seven seconds can we drop, and that is the distance the ride will be.

And that's quite a critical calculation because if you make it too short, people aren't going to be thrilled. They're not going to be scared. If you make it too long, for every extra inch of steel work you create, it's going to cost tens of thousands of pounds. So there's a not only a psychological, but there's an economics kind of modelling behind this whole thing.

Amy Barrett

Absolutely. So in nought point seven seconds, how far did you drop them?

Brendan Walker

Cool, God, I'd have to go back now, to my calculations. Let's see. I think it was in point seven seconds I think we were, that was formulating response, so I think that was around three metres. Sorry that was to detect that something had happened. I think it's 1.2 seconds that it took for the 95th percentile to formulate a response and that was just over seven metres, but people who've ridden 13 will probably know that it doesn't drop you seven metres, it's actually more like five metres and the way we do that, we shaved off another two metres of steelworks, saving 10s of thousands of pounds, was to pump prime the brain.

So we drop the people in the dark, a very short amount of time, the brain suddenly goes right, I understand what's going to happen next. And the second time we've dropped them, which is much further it takes the brain much less time to process that information.

So again, it was a an awareness of psychology and this sort of pump priming that we were able to reduce the amount of steel work and still critically deliver the thrilling experience that people were expecting.

Amy Barrett

But in any other situation a drop like that would frighten the hell out of me. How does that turn to thrill and kind of excitement at that point?

Brendan Walker

Yeah, I feel like I I my job's terrorising people. There's see, as animals, we have a really strong relationship with thrill. So, in evolutionary terms thrill has evolved as a mechanism to reward the persistence of life.

Now whether that's evading danger, and not being killed or maimed or suffering any kind of morbidity or mortality, all the way through to reproduction, sating hunger, quenching thirst, chasing prey, these are all quite exciting things. And in modern life, modern society we very rarely, particularly in our western world, we're very lucky in some senses, we don't experience those extremes. But to feel thrilled is to feel truly alive.

I mean, these are at the extreme ends of our emotional experience. But in a world where we don't feel thrilled, we feel flat, we don't feel excited. So theme parks and roller coasters part of their appeal is because they're replacing those mechanisms that did used to naturally exist. But whereas in the wild, we truly were faced with real dangers, the job of a theme park is to create the perception of danger.

And so we are we all allow ourselves to be immersed in this, this play, this world of play, where we all go along with the idea that we're actually in danger. But actually the the danger of any accidents at a theme park you're more likely to fall off a donkey in Skegness than have any accidents on a theme park ride.

Amy Barrett

Is that true? Really because there's i know a lot of people who do you really hate, hate rides and are anxious that, i mean i for me when I see them going around, I think how on earth do you go upside down and not have the wheels drop off? What What would you say to people that have that fear?

Brendan Walker

Well, those. Thomas Miller actually designed the up stop wheels, which are the things that keep you from falling off the track. And I'd say if you trust wheels to keep you on top of a track, you can trust those wheels to keep you underneath the track, that's for sure.

But he has that patent for that was over 100 years ago. There are many patterns like that to do with health and safety, which have evolved over 100 years. And i mean you can look at the statistics. I mean, they say that, yes, you're safer on a roller coaster than you are in a civil aviation airliner.

But that doesn't help most people. I think the fact that you're strapped to several tonnes of steel work hurtling around a track sometimes up to five g is a most terrifying thought. But, you know, I think you should, I mean, two ways you can actually combat that. One is to think about it objectively, that this really is a very safe mechanism, and actually, I am strapped to probably one of the most safest experiences on the planet.

And the other thing is, yes, you should be scared, because that's what it's designed to do. So, in some sense, embrace it. But also, if it's not for you look for rides which don't invert, ones that are less extreme. And even if they're no good for you, go and hold the coats of people who go on and live the experience vicariously, so enjoy them as they're screaming. And even if it's only that - that amount of a sensation that you can stomach literally - that still may be thrilling for you just to be present and watching other people having that kind of experience.

So you can experience all kinds of levels.

Amy Barrett

But up to five g one, what on earth, what happens to our bodies when you go to five g?

Brendan Walker

A lot less than when you're going up to 10 G, that's wheret, there are... If you look at the rocket sled experiments by Colonel John Step, who was the RAF medical officer and he was also a test pilot. He self tested, and I don't think it'd be allowed today, he put himself on rockets sled experiments and went beyond 10 G. This was laterally going forwards.

He detached his retina. He caused all sorts of haemorrhaging. I mean, it was, he survived, but he was like going well, where are the limits, and I think he found them. But that led to the invention and evolution of G suits.

And so specifically what happens depending on which way you're facing, if you're on a superman type ride, you're facing headlong into the way you're going if you're sitting on a standard ride. So the forces are pretty much going through your body.

And the way that rides will work is, you know, all the banking and all those twists and turns, they primarily try to maintain the, the majority of the G forces acting through the body, so through your head down through your spine, through the seat of your pants and to the seat below you. And that's because we're pretty good at withstanding g forces in that particular plane.

But if you sustain them for any period of time, that that kind of force will drain blood out of your head, so you'll start getting white outs, or blackouts sorry, and if you go the other way, you'll start getting red outs and grey outs. I have to check this actually the right way around. But essentially blood is going to your head or from your head. So blacking out is is a real possibility.

But on rides rollercoasters, we only experience 5g for momentary periods. In fact, they usually mark transitions between different forms of motion. And then, they can be the thrilling moments when we hit those peaks.

But you should know that we we don't experience them for any length of time, we're constantly changing, which is one reason why experiencing those kind of G forces of that length of time is safe, unlike a fighter pilot who might experience 10 G, and have to hold that in a turn for many seconds. And that's one reason they have these pressure suits which apply pressure to the body and make sure that blood pressure is maintained to the head so they don't pass out.

Amy Barrett

So are there things that just couldn't be built into a roller coaster because they're too scary or potentially too dangerous?

Brendan Walker

Yeah, I had a student at the Royal College of Art who did his PhD, and his final thesis was the design of a euthanasia coaster, which took people, they got on it, and it went through increasingly tighter loops, increasing the centripetal force consistently. So first off, you'd black just black out quite nicely. But then ultimately you would haemorrhage and die.

He said it would be a pleasurable death. But I, I'd hate to think I mean, I would like to the first person to test it. That's for sure. So, I mean, because you have to ask your question again. Sorry.

Amy Barrett

Is there anything that's too dangerous to build into a roller coaster?

Brendan Walker

Yeah, so I think jet Yeah, so obviously, yeah, so incredibly tight radius loops, which will generate g forces above five G, they will be quite dangerous. I mean, whiplash is also an issue. So if you go into a curve too quickly, the transition between straight movements and curved movement can create a spike in G. So even though the sustained movement around the curve might be something like five g going into the curve might be 10 g. so and that's Also one reason why these teardrop shaped loops have evolved these - they're called clothoid loops - which take you in gently and then increasingly get tighter in the curves.

So curves, that's all you have to watch out. Sudden changes which can cause whiplash. I mean, they are pretty bad. But no apart from that, as long as your body is kept clear of anything that might hit it. I think trauma and rapid changes in forces are the worst things that could happen to you.

Amy Barrett

But none of these things ever find themselves into actual rides? I'm assuming you spot these things at what kind of stage in the testing?

Brendan Walker

Well, there are companies like Gerstlauer in, in Switzerland who do a lot of testing on there so that they are very big firms. They're almost like three dimensional train manufacturers, and their level of engineering and precision is quite phenomenal. So they will do computer modelling at a very earluy stage and work out the, the forces that are going to be applied not only to their carriages, but also to the rider.

And there are various things you can do, if you want to roll somebody, but you don't want the blood to go rushing to their head, you can put the centerline of that roll through the - well they call them Hartline rolls - so, you put the the centre of the roll around the centre of the body and the the body is kind of evenly distributed around this this kind of barrel roll.

So, there are ways to, to optimise track layouts for the comfort and the safety of the rider, but we are reaching limitations. I don't think there are many things on a roller coaster which would feel nice and be safe that currently isn't being being done.

In fact, the founder of Gerstlauer is Werner Stengel and he's in his 80s now but a lot of the features like the cobra roll or the little bunny hops that you get on rides, I mean the cobra roll sort of ride where you sort of swoop up and then back down on yourself, a little bit like you might imagine a helicopter doing a kind of U turn. That's one of his signature curves, but he's got a real kind of tacit understanding of what feels good, but I think a lot of that language he's already worked out. Everything else on that is kind of riffing on the same, on the same music now.

Amy Barrett

So what is in store for the future of rollercoasters and rides?

Brendan Walker

Well, for the future of rides, I've been particularly fascinated with the use of virtual reality with in fact actually any technology. I initially started looking at ways to broadcast video from rides exactly for the reason you're talking about people who might not want to be on the ride themselves, but might want to see what's happening to somebody on the ride.

So being able for somebody on the ride to be able to broadcast their experience to somebody on the ground completely changes the social dynamics of what's going on, and enables somebody on the ground to live vicariously through the eyes of the person who's on the ride, but also the person on the ride, realising that performing to somebody on the ground and that element of performance. So if you encourage yourself to screen even if you don't feel like screaming, it's been shown that that that can also pump primary emotions.

So there's all sorts of dynamics that changed just with that technology. But most recently, I've been looking at the application of virtual reality onto, onto amusement rides. I think roller coasters aren't the right kind of ride to take VR because the pleasure of a roller coaster is being able to get that high vantage point to see the real world ahead of you and appreciate your movement through the world on this architectural scale.

But there are other rides, simpler rides I'm working on which you probably find at the fairground, which are much sort of, thet're circular flat rides, they don't invert, but with applications VR, I can reverse engineer the physical forces that the ride is being felt, and then create a virtual world that makes the rider believe they're on a ride, which is much more extreme than the one they're actually on.

And I think for me, that's, well, that's where my excitement is at the moment, trying to augment all these existing but what people perceive to be not very thrilling rides, and I'm hoping to up the ante on those.

Amy Barrett

And you've mentioned that when you're working on Wicker Man and you wanted to make that was sort of maybe novel, something people hadn't seen before. If you're always seeking bigger and bigger, more novel thrills, would there be, would we ever come to a point where nothing would actually thrill us anymore?

Brendan Walker

Yeah, I think with I mean, the scientific definition of thrill is, is the, is our response to novel stimuli and so from generation to generation, what was novel for my dad and my granddad is no longer novel for me. So I'm looking for something new. And that can be new culturally, it can be new sensations.

And so yeah, we run out of superlatives. And it's one reason when you look at the marketing of new rides, it's always 'the fastest', 'the highest', 'the most number of loops', it's all and when we gravitate towards novelty, it's in our human nature to need novelty. So we will just find other things to, to become novel.

So it could be the application of technology. I mean, fairgrounds themselves, it was the first place that most people in the UK experienced electricity because they'd never seen electricity before we go to the fairground, you suddenly see electric light bulbs. So, and same with cinematic prediction first appeared at fairground, so, the fairground and amusement parks have been a place not only for novel sensations as in physical forces, but also novel forms of technology.

So I don't think we're ever going to run out of novelty. As long as we're still inventing, we will always, in fact, always think, generation to generation, we're always looking to ride the latest technological innovation. And that will always be true.

Amy Barrett

And how important in, in creating a thrill is the story of a ride or the magic of a roller coaster because they will have sort of themes?

Brendan Walker

Yeah, that theming can be quite important in a ride. I mean, there's two reasons one is from a marketing perspective, and, and actually marketing is very important because when you look at the the overall thrilling experience, it starts right at the moment you see a poster which shows a ride, promises to deliver a thrilling experience, which is all part of the marketing. That's what It really captures our imagination.

And then we start to build a picture in our mind of what that ride might do to us. We buy a ticket days ahead, we start to get excited, we're going to go on that ride. So the marketing and the theming is really important because it gives us a way to understand the ride, and what it might deliver to us. And particularly, we can talk to other people that's most easily communicated in a story.

When we get to the ride itself, for a ride like Wicker Man, there are, let's say chase sequences or moments you want to avoid danger. So those can be borne out in a kind of loose narrative. I mean, as I said earlier, the, the majority of the emotional experience comes from the twists and turns and the physical accelerations we feel on a ride. But the narrative does give us moments of spectacle and excitement and also give us a way to experience and contextualise those movements.

So again, it's a little bit like seeing a kind of avant garde modern dance I suppose. It can seem a little bit hectic sometimes. But as long as there's a strong underlying narrative we can fall back on that usually helps take us through the experience as a, as a an entire entity.

Amy Barrett

You have heard that the most exciting part of a ride is usually when you're getting strapped in, is that not the case?

Brendan Walker

Yeah, some of the experiments I conducted at Alton Towers, particularly on Oblivion, which was the world's first vertical drop roller coaster. And we notice because I was monitoring the the physiology of people getting on ride, so we were looking at their heart rate, their galvanic skin response, which is how sweaty their skin becomes, and also looking at their facial expression. So we had head, head cameras looking back at their faces, so we're looking at elements of pleasure and arousal.

And we were hoping to capture people's experiences as they went over the edge of Oblivion. So Oblivion's got one feature, you get taken to the edge, your carriage dangles over, you're held there for two seconds or so looking straight down, the brakes taken off, and you go plummeting. And we wanted to compare different people's responses to that moment, and compare that against their different personality types.

But we had the recorders going all the time. And so before people even got on the ride, we started all the medical recording equipment. And we noticed as the, the bars were being closed over people's shoulders, these restraints, their readings, shot up, their levels of arousal went to well, the actual feature itself only ever achieved 80 per cent of the levels of arousal that we achieved when we actually locked them into the ride.

And we think that that that's really to do with the amazing amount of anxiety or anticipation or excitement about what's going to come in the minutes ahead. And also it's a point of no return. Because up until that point, you've thought you're gonna go to the theme park, you've bought your ticket, you've walked to the ride every single step along that way, you can always turn back.

At that moment, there's a compression of time as that bar's coming down. It's the very last second, you can say, 'No, I want to get off', and then you're locked in. So I think there's this compression of time and commitment to what's going to happen that is, that's what's going on in that moment, is compression of experience.

Amy Barrett

And you mentioned that you've captured photos of people's faces. What kind of facial expressions, do we all pull the same ones because I can imagine we all look horrendous, when we're on roller coasters, but is everybody's face doing the same thing? Are we going through the same emotions?

Brendan Walker

Well, I've noticed on well I've done experiments on people watching horror films, and I've done experiments watching people's faces on rollercoasters and other rides, and I expected to see a fairly consistent kind of emotional response between people. But that's it. It's, it's really not true.

And I can explain in several ways. I mean, people's facial expressions have gone through moments of delight. I mean, we have 43 different muscle groups in the face, and any combination of those can express different emotions that we're feeling inside, and Duchenne was the first person to start logging that. And Charles Darwin in his book expressions of emotions in humans and animals progressed that thinking and then more recently, Paul Ekman started to codify it and that's why computers can now automatically detect human emotion expressions, just looking at these 40 different muscle groups.

So I was interested in using those kind of techniques to understand people's emotions on rides, but people's emotions were fluctuating all over the place. If you actually chart pleasure against arousal and place all the emotions on this chart, people were going well, particularly in all the extreme emotions, both positive emotions, high levels of pleasure and negative levels of pleasure. And, and their facial expressions change. They were constantly in flux, to an extreme excitement, delight, joy, happiness, all the way through to terror, horror, sometimes boredom as well.

And, but the critical thing about thrill is that thrill isn't an emotion itself. It is the change in emotions. And so if there's a rapid and large increase in pleasure and arousal, it's this movement, this dynamic movement, then we get a sensation of thrill. So for me as a thrill engineer, this was really good news that we've got these rapidly changing mixed emotions.

In one of the experiments I conducted, one of the very first ones working with a scientist from MIT, who created this galvanic skin response monitoring device. I put people on fairground rides, and used the technology to fire a single use camera to capture portraits of riders, and those 10 portraits from different rides, absolutely set in stone, this range of different emotional experiences experienced across these different ride types.

And that has been, mirrors some work that an artist did in New York in the 1960s. He had an exhibition of photographs taken of people at their moment of orgasm. And he showed these photographs without any contextual information, and the majority of people who saw this experiment thought that people are either being murdered or tortured, or in some some way experiencing an, you know, an unpleasurable experience.

And it was just because he'd managed to capture the moment, either just slightly off or just before. But there's this, this amazing flux and change in emotions during these very extreme emotional experiences. It's just incredible.

Amy Barrett

It's such a fine line between the fun side of fear and actual kind of believing a real threat.

Brendan Walker

Oh, yeah, absolutely. I think that and that's where that's where, you know, if I'm working with a university, so I'm currently professor of Creative Industries at Middlesex University. And if I were to do an experiment through a university, particularly through a psychology department, if you're saying that you're going to make people believe that they're really in danger, you would be in their ethics committees for years

Yet in entertainment, there is, because there's this sort of tacit understanding and a kind of contract, that it's an unspoken contract. It's an unwritten contract between people who go seeking entertainment and those who provide it. The people going into those amusement parks are saying, I want to be challenged, I want to be taken to the edge, to this dangerous edge, but I trust as part of this agreement, you are agreeing to ultimately be keeping me safe.

And so I think talking to your friends about those ones who are scared to go on rollercoasters, I think you can reassure them with that. I mean, that is the contract that's always being presented between the suppliers of amusement and thrilling experiences, and those who seek it. We all know that this is the game but nobody ever states it.

Amy Barrett

And would you ever put yourself in that thrill seeking, would you consider yourself a thrill seeker?

Brendan Walker

Gosh, I, I always thought of myself as a real thrill seeker I, you know, I, I own a motorbike, but I don't drive daftly, I'm quite safe on it. I like unusual experiences. But sometimes I'll chicken out. And I have this sort of kind of love/hate with thrill and it's not a love/hate, it's more like a, I think my perceptions of risk are quite low. So the things I'd really love to do, but whether it's social, or whether it's actual body harm that I'm worried about, something prevents me. So I'm constantly conflicted. But I do love watching people on rides. And one reason why I've become a thrill engineer is to make experiences for others to experience that I can live vicariously

And this intrigued me and and part of another research project I did. I went to see if I had the thrill seeking gene because part of our, our reasons for thrill seeking can be put down to genetics as well as personality types. Yeah, there's a there's a gene, the on chromosome 11, the gene, the D4DR, which is the dopamene receptor gene.

So, when we experience pleasure, the body releases dopamine, dopamine binds to the dopamine receptor, which gives us this real sense of euphoria and this is the reward feedback we get, you know, and it can be a problem because it can lead to addictive behaviour, such as addicted to gambling even drink, but in roller coasters, think right in roller coasters.

We rely on this burst of dopamine. But if you have a polymorphism, this is a defect in this D4DR gene, it means that it can't bind to dopamene, as well as efficiently as, as other receptors. And so this means that the body needs to produce more dopamine to give the receptors a better chance of picking it up.

So which is another reason why people might be termed thrill seekers. But they're not seeking adrenaline, they're not adrenaline junkies, that isn't the better thrill they're looking for. It's the other part of the emotions. It's the pleasure that they're really missing.

So I think there's always a misconception that thrill and adventure seekers are high octane adrenaline seekers. It's all about doing dangerous things, dangerous sports. Actually, that's only half the picture. And it's the other half of the audience that really intrigued me. It's pleasure seekers that are the, the often-neglected forms of thrill seeking.

Amy Barrett

So did you find out if you had what your gene looked like?

Brendan Walker

Yes. I'm glad Yes, I did find that I had this polymorphism and I am, I am a bonafide thrill seeker. I kind of like think, am I now some form of emotional cripple that I need to go and seek greater extreme experiences that my grandma might have experienced for a much lower level? Maybe I am.

But I'm not unusual there are in the UK there are about, I think around 1 in 30 people have this polymorphism polymorphism, which you know, if you're at school, you would say, in every classroom there would be one person like you.

But when you go to the US and Australia, the proportion's about one in 20 and this is thought to be that the people who had this thrill seeking gene were more likely to be adventurous, more likely to go and colonise these other worlds. But then you look at other nations such as China, I think that their currents there's about one in 60. And again, they have a very different attitude to, to adventure and going out and seeking new places. So it's quite fascinating once you start charting it on a global scale, who's got this polymorphism.

Amy Barrett

It's fascinating, had no idea there was something perhaps there's something I can say is not, not to blame for my, my thrill seeking. And so tell me, if I, whenever this happens whenever I get a chance to when I go to roller coaster next, where should I sit to get the best thrill out of it? Am I supposed to sit at the front, the back, on the edge of a row?

Brendan Walker

Right so, so that if you sit at the front of her Okay, so we're just talking about a traditional roller coaster you might see on American film, something at Six Flags. If you sit at the front, if actually the best way to think about roller coaster is think about where its centre of mass is.

So generally, if you sat on a long roller coaster at the centre, that will pretty much match your experience if you're a sat on or a coat on a roller coaster, and it was only one car. So that experience of just going around by yourself in one car, much like you might on a ride like Smiler or Oblivion at Alton Towers.

If you're on a long roller coaster, you sit at the front, then your experience precedes the experience of the one at the centre. So for example, you will be 10 metres further. So for example, if you're going over an edge, you'll be hanging 10 metres down the front, before the entire train starts accelerating away. And similarly, you'll go hurtling over the top of a hill where you'd normally think I should be slowing down, but you're not because the rest of the train still pushing you. So it can be quite disconcerting.

At the back of the train, you can actually be whipped around a lot more. In fact, your speeds at the back are, feel much greater, even though they're not because you are doing that thing that you've gone over the hump of the hill. The trains dragging you now down over the other side, and you're accelerating, even though you're going up.

So depends what kind of experience, one is, I think at the front is slightly more unnerving and a slightly more out of body experience. The experience at the back is much more thrilling, and unexpected, but if you want to have a normal, well let's say a relatively normal experience Is your a little bit wary roller coasters, sit in the middle.

Amy Barrett

And when I do get to go out and try this, this one thrill after the lockdown, what would you recommend?

Brendan Walker

Gosh, try any thrill or a ride.

Amy Barrett

Ride a ride perhaps in the UK I can go to.

Brendan Walker

I think the most accessible rides, I would, for my money I would go to the fairground, and I would find a ride called the orbit, which was one of the first fairground rides, which didn't just do circles in circles, but the arms raise up and they throw you a little bit like as if somebody was throwing balls around in the air.

It's really compact ride and so the motions you get are really intense. And when I found out that the people who invented that ride and manufactured it, actually were more used to making oil rigs and making oil drilling equipment, I thought I, it suddenly all made sense if you imagine diamond-tipped blades at the end of these arms whizzing around, and it boring underneath the Channel Tunnel. I think you kind of get the idea. So that for me really brings a ride like that to life. And I think they're much more accessible. So you can go and find your local fairground, find an orbit and get on it.

Amy Barrett

But until that point, well can sensation seekers do a lockdown to get their kicks.

Brendan Walker

Wow. So while I'm working on something right now on a thrill ride, which is a virtuality thrill ride, but for rowing machines. So once I finished that anybody will be able to ride that and they'll feel like they're propelling themselves around a roller coaster track. So that's one to watch out for.

I've seen a lot of people using VR but I think without movement. I think VR can be, you know, it's like playing a very good computer game, but other thrilling things you can do at home...

I think they have to be much more social. So I think finding ways to use telepresence, and games. So some people are finding physical board games and physical activities that are combining telepresence, so remote connections between people.

I think that that's always so i'd concentrate more on the social aspect and linking up with people, but trying to think about how to reinterpret existing games. They might be parlour games. I don't know. Can you play a game of Twister over with remote distancing over video? I don't know.

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