S4 #50 How can we choose pro-environment and how does it improve our well-being? Brain-to-brain with Dr. Zoé Bollen.

Welcome and introductions

0:00Hi, and welcome to Kaleidoscience. Here you find answers about cognition that you may or may not have asked yourself. This episode is hosted by Imogen Huesing and Sophie Kuhne. So sit back, relax, and enjoy this week's episode. We are currently in August, while experiencing one of the hottest summers ever recorded with wildfires all over Europe, including France, Spain, Greece, but also more northern countries like Belgium, the Netherlands, and even Scotland. There are many more wildfires in many more countries. This makes it even more urgent to act more environmentally friendly

0:35and prevent further catastrophes as much as possible. Today we want to talk about the psychology behind environmental decision-making. For that, we are glad to welcome our guest today, Zoe Bolen. She completed her bachelor's, master's, and doctorate in psychology at UC Leuven in Belgium, focusing on the impulse system in people with severe alcohol use disorder. After shifting her research focus to the cognitive mechanisms behind pro-environmental behavior in two postdoc positions at the universities in Basel and Bern,

1:06she has returned to UC Leuven as a postdoc to explore attention mechanisms and environmental decision-making even deeper. Welcome to our podcast. We're really glad to have you on. Thank you very much. Thank you for the invitation. Okay, now we're going to start with a beloved welcome game. So I'm going to give you the beginning of five sentences. And you should just spontaneously answer just whatever comes to your mind first. As a kid, I always wanted to be...

1:37I think I want to be like a writer, like a storyteller. Like I used to write little stories and nobody read it, but I liked that. And then I wanted to make movies. But yeah, in the end, I didn't do that at all. And I think now I just, I'm more enjoying listening to other people's stories and yeah, just change.

2:08So like little fictional stories. Yeah, yeah. More like that. Yeah. That's very fun. If I was an emoji, I would be... I think I would be the little son with the smile. Like I think it's a really peaceful emoji. I don't know if you see which one I'm talking about. And I don't know. I'm not always peaceful, but I'm trying to be as much as I can. And I feel great every time I see this little emoji.

2:41That's really nice. And my favorite thing to do on a day off is... I live in Brussels. So I think I would say that a perfect day off is just to like see my friend in Brussels having a brunch or I don't know, breakfast with them, chatting. Maybe go in a park and then just finish the evening again with friends having a drink and going.

3:12Going to dance. Yeah. Something like that. That's very nice. Very social. Sounds really fun.

3:21Right. Now I'm most fascinated by... I think that's completely about what you said just before in the introduction. But I'm very interested in the impact of the environment on us, on our decision and like the impact of air pollution or heat waves or even like when you are in real nature, like how this can impact our decision or emotion.

3:52Because I think most of the time we really underestimate how the environment can impact us and can impact how we make decisions or stuff like that and like how it impacts our everyday life. And yeah, so I would really like to go a bit deeper into that. Yes, we will discuss this a little bit more in a second, I think. I know it's time to call it a day when...

4:25I think when it's over for me, I really can't feel it in my head like my brain is not functioning properly anymore. So I don't try to continue. I just stop my day, relax, and I know it's going to be even better tomorrow if I stop at the right time. So I don't know. It's just a feeling, but I know exactly when I need to stop.

4:55That sounds really healthy.

Zoe Bolen's scientific journey

4:57Yeah. Okay, we already touched on your background, but could you tell us a little bit more about your scientific journey and interests and how that led you to where you are now? So yeah, I did my study in psychology at UC Louvain in Belgium. And when I was in my master's, I think I was really interested in both neuropsychology, so it's more about all the cognitive functioning is related to brain areas and how it can impact when you have brain damage, for example.

5:39So like memory, attention, and so on. So I was really interested in that and also in addiction. So we had some courses about how substance or drugs can impact our brain, can create addiction, or it can also influence our decision or behaviors and so on. So I was really interested in both. And I think that's why I did my master's thesis and my PhD thesis on this topic.

6:10So my PhD thesis, supervised by Professor Pierre Morage, was about attentional bias in alcohol use disorder. So it's the idea that when you have an alcohol use disorder, your attention is supposed to be biased and to be directed to alcohol-related stimuli every time alcohol-related stimuli is in your environment.

6:40So it's like an automatic tendency to look at alcohol. And this then will increase your craving for alcohol and lead to more alcohol consumption. So it's like a vicious cycle, and it's getting worse and worse because of this neurotoxic effect of alcohol, which also increased this attentional bias. And so we wanted to test that, and we used an eye-tracking measure, which I will maybe discuss later, and to see how this attentional bias works, if it's really there, and really understand the mechanism behind that.

7:23And so I really liked that, but then I was more and more personally interested in climate change, also very concerned about that. And so I wanted my research to be more linked to my environmental values. And I also saw that there was more and more research on that and how our behavior is obviously connected to climate change, but how some people want to act on that, or what are the barriers and the levers for environmental behavior.

8:03And so that's why I changed after my PhD to my postdoc. I changed my research field, and I did a postdoc at the University of Bern and University of Basel with Professor Daria Knock and Professor Ulf Anel. And there we really studied how pro-environmental behaviors are made, and to do that, we used, again, eye-tracking, so that's kind of the connection between all my research, and just to understand not only why or who makes pro-environmental decisions, but more like how these decisions are made,

8:50so what are the mechanisms are made, so what are the mechanisms behind pro-environmental behaviors. After my two years contract in Switzerland, I went back to Belgium, so I started one year postdoc with Professor Alexander Ehren, and we started a study in which we wanted to see how exposure to nature can influence our attention, how exposure to nature can influence our attention, but also our emotion, and how this can be also impact based on the degradation of the environment.

9:25So when you have, like, litter or trash in the forest, how this could actually reduce the benefits that we can have from nature. Because there is a lot of studies showing that when you are in nature, your positive effects can be improved, your negative effects can be reduced, and also it asks way less directed attention, so you can, like, have a effortless attention, which helps you to recover and, like, to restore your attentional resources.

10:02So there has been a lot of studies on that, and we wanted to kind of replicate this effect, but by using a study that was directly in a forest or in front of a urban building. But we also add some litter in the forest, so that you can see if this can have an effect. So that's, yeah, that's what I'm just working on right now. And then I will start another postdoc with Professor Tamien Brevers.

10:36And here we are going to investigate how pro-environmental behaviors and pro-social behaviors are connected and how, what happens when they are both in conflict or, like, when they are actually going in the same direction. So that's, like, the next big project. So, yeah, that's basically it for my background. Very cool. Thank you.

Studying environmental decision-making

11:06Okay. You already mentioned a lot of things, but let's dive in. So let's start a little bit more with a broad question. So why do you think it's interesting or maybe even necessary to study environmental decision-making? I think because we know that global climate change has been caused by human behaviors, by, like, individual behaviors.

11:39So the way we behaved in the past had an impact, and the way we are going to act in the future is going to have a huge impact on our future. So behavioral science here makes complete sense. Obviously, obviously, it's not only about individual behaviors. There is also, like, the connectivity, the society. But I think it's really interesting and important to understand how each individual makes decisions, like, how they behave,

12:13so that we can then make the pro-environmental behavior easier for everyone, like, or easier for depending on certain groups. Like, we know we are not all making the same decision in the same way. It depends on a lot of different variables. So if we study these variables and if we study the mechanisms behind behaviors, we can then help policy intervention and, yeah,

12:43just get a better understanding of all this behavior to then be able to have a better models of pro-mental behaviors and then better intervention and, like, for policymakers also. And how do you go about studying decision-making? So what does it mean to study decision-making and how can one study decision-making?

13:13There are different ways. Like, you can, for sure, use a neuroscience method to study that, like EEG, fMRI. You can use a different paradigm in which you ask participants to make decisions every time and this decision has an environmental impact and they can also, like, earn money and stuff like that. And then you see how they make their decision based on different information.

13:43You can also make this task, like, real. So the consequences of the task are real. So that's what we did in some studies. So we said that one of the decisions that they have to do in the experiment, one of them will be randomly selected and then we will really implement the consequences. So that means that, for example, you can use a donation task. And so you say that in the end we will give some donation to NGOs that are working for the environment.

14:15Or you can also use the emission trading systems where you can buy some carbon certificates so that the emission that some companies are allowed to emit based on the certificates. If you take some of them on the carbon market, they are no longer available for these companies to pollute. So it's kind of one way to do that.

Using eye-tracking in experiments

14:41So there is a lot of paradigms that have been developed to study parental behaviors. And my personal way, like, I mean, I want to do, to use different tools, but one way that I'm using is always eye tracking. So eye tracking is a technique that allows to know where the eyes are going, so where you are looking.

15:11And it's just like an infrared camera that detects the reflection of the pupil and the corneal. And just with that, you can see very precisely where a participant is looking when you are, for example, presenting a task on a computer. And with that, you can then know what participants are paying attention to. So if you show, for example, this information for the paradigm, I told you, like, you show that there is some environmental consequences on their decision, but they can also, like, make some money based on the decision.

15:48So they get information about, like, the money they can get, but also, like, the carbon emission that they will emit based on their decision. Well, with eye tracking, you can then see if they looked at the money more than the carbon emission, how long they look at each information, which information they looked first, and so on and so on. So it really helps you to better understand how the decisions are made before it's actually made. So really, like, the decision-making processes. So basically, with the eye tracking method, you are assuming that the aspects where they pay more attention to, where they look longer at, that that plays a larger role in their decision-making?

16:33Yeah, exactly. There has been a lot of eye tracking research in decision and, like, on other topics. And we can see that the more you are paying attention to an information, the more important this information is for you. And so, for example, there has been studies with pro-social decision, and you can see that people that are more, like, individualistic, they will pay more attention to, like, their own payoff.

17:06But people that are more like altruist or, like, more cooperative, they will also look at the other payoff, the other players' payoff, for example. So it's just, like, the more you are paying attention to one information, meaning the longer your fixation is at one information, the more important it is for you. And you also mentioned that you are interested in where people look first.

17:38Why is that interesting?

17:42It's nice to have, like, different measures. Like, the most common one is how long you looked at one information compared to the other. But you can also have a look at, like, the time sequences of your attention. So which information you looked first could indicate, like, pre-existing preferences. You know the information are going to appear. And you know that the information about, like, the monetary bonus is going to appear on the left.

18:16Well, if your first fixation is on the left, that might indicate that this is really what you first want to have a look at. So it can give you some information about, like, preferences or, like, attitudes that are already there. And you can also have a look at the last fixation before the decision is made. Because this information could actually be the information that was decisive for crossing the threshold from, like, which decision am I going to make to, okay, I'm going to make this decision.

18:54And that's because I saw, I don't know, that the carbon emission was really high. And then I was like, okay, that's helped me making my decision. Let's go for that one. So last fixation can also be an interesting measure. I think that's really interesting.

The carbon emission monetary study

19:11And you did an eye tracking study on pro-environmental decision making. So you have people in the lab and they are looking at options. Can you explain a little bit more how that works or how that looks like for a participant? Yeah. So we use this paradigm that I told you about. So basically, we say to participants that they are going to be presented with an offer, a monetary offer.

19:43So they can earn, like, 5 euros to 25 euros, depending on the offer. But if they accept this offer, then they will also emit some carbon emission. And it's, like, from 20 kilos of CO2 to 110 kilos of CO2. And so each offer, they see it on the computer. And they just have to say whether they accept or decline the offer. And that means that every time you accept the offer, you are making a decision that is bad for the environment because you are going to emit.

20:17While if you decline the offer, you don't get any bonus, monetary bonus. But then you are acting for the environment because you can stay carbon neutral. And what's important is that we said to the participant that at the end of the task, we will selectively, like, randomly select one of the trials and then really implement it so that they know it's real, like, the consequences are real. And with eye tracking, we just put an eye tracker on the computer when they were making this task.

20:48And we could then see how much time they spent looking at the monetary bonus that they can have with this offer and the carbon emission that was associated with the offer. So the two information were at two different parts of the screen. And we just then had to look along the look at each information, which information was first fixated, and so on. And what we really wanted to know is whether our environmental attitude can influence how we pay attention to this information.

21:26And that maybe then the way we pay attention to this information can help us predict the decision. So, like, attention is kind of related to our attitude and our behavior. And our finding was that first, our environmental attitude, so the way the environment is important for us in our everyday life, how much we act for the environment in everyday life.

21:56This actually influenced how we pay attention when we have to make this kind of decision. And we could see that people with stronger environmental attitude actually paid more attention to the carbon emission of the offer. So, actually, they paid more attention to the environmental consequences of their decision. And so, we could see that with the fixation time that they spent on each information. But we could also see that if you had a stronger environmental attitude, you also looked first at the carbon emission more frequently than the monetary bonus.

22:33And then we also looked at whether how we pay attention can influence our decision. And we have seen that if the participant had spent more time looking at carbon emission, they are more likely to then make a lot of pro-environmental decisions. But we also see that it kind of depends on what was in the offer. So, if the cost was quite small, so that means that the bonus that they decided to decline was quite small,

23:09then attention can really predict the decision. But when you have a huge sacrifice because you have like to sacrifice 20 euros, for example, then the way you pay attention to this information is not enough to predict your decision. So, maybe it's because it involves higher level cognitive processes like self-control and so on, because then it's much more difficult for you to make this decision and attention is not enough to explain. So, that was really interesting because we could see that the way we pay attention to information play a role in decision and is influenced by our attitude.

23:52But the more important thing is obviously what is the decision? So, what are the stakes of the decision? So, if there is a very high personal cost or very high environmental benefits, that's going to obviously influence your decision. So, you have to look at a bigger picture and not try to predict decision just based on one thing. I have one more question about the concrete study design.

24:24Like, were the price and the carbon emission proportionate to each other? Like, were the carbon emissions higher when they were offered 20 or 25 euros or was that randomly balanced?

24:38We didn't use like a fully cross design in which you had like every different amount of money with every different amount of CO2. But we tried to have a mixed so that we had sometimes a very low monetary bonus with a very high environmental benefits. And so, here the decision is a bit easier to make because the difference is too much. But we also used other trials that were much more difficult because you actually have, I don't know, like a high monetary bonus, but also a high environmental carbon emission.

25:18So, we tried to make the difficulty of the decision varying between trials. All right. And you said that you basically enacted on one of the random trials.

25:35If it was a trial where the participants received money but decided for carbon emissions, how did you do the carbon emissions? Yeah, that was the tricky part because, like, we say that they are going to emit. But actually, when we give the instruction just before starting the test, we explain a bit more in detail. And participants are not really going to emit carbon emission because that's obviously important for me that my task is not actually emitting emission while I'm studying parental behavior.

26:14So, that doesn't make sense for me. So, what we – and I didn't develop this paradigm. It's actually the carbon emission task by Sebastian Berger and Annika Ries. And what they explained in the instruction before is that if the participant had declined the offer, they don't get any bonus. But then we will buy CO2 certificates for the amount of carbon emission that were associated with the offer.

26:46And so, we buy this CO2 certificates on the carbon market so that this emission are no – so, these certificates are no longer available to industrial companies to cover their own emission. So, that's like we take this CO2 certificate, we just destroy them. So, it's like we save this carbon emission because the participant decide to decline the offer. But if they accept the offer, they get the monetary bonus, but then we don't buy any CO2 certificates.

27:21So, it's like a bit – either they can like save CO2 certificates or not, but we didn't want to frame it that way because in everyday life, you don't really save CO2 emission. It's more like you try to reduce as much as possible your carbon emission. So, we wanted to frame it like that, but in the instruction, we explain in detail that it's actually with the CO2 certificates and there are not really – there is an entire consequences, but it's not that they are really emitting carbon emission.

27:53I think that's really cool because, I mean, these decision-making paradigms are often used in psychology, but most of the time, they don't have any real-world consequences. And I obviously hope that most participants try to act as honestly as they can despite that, but I think it's really cool that you actually implement these choices in the real world.

28:24Yeah, but there is a move in the field, like before, a lot of people used hypothetical scenarios or self-reports, and now there has been a call for more research using like real consequential paradigms. Obviously, obviously, also because climate change is quite urgent, so we need to know how people actually decide when there is real consequences and not like hypotheticals.

28:55But yeah, there are a few paradigms with these real consequences, but I think they are really, really nice. I think it's really cool. So, I don't know much about these decision-making paradigms, but when you have a monetary option, which is something very practical, a lot of people experience in day-to-day life, and something like CO2 that is more abstract, did you check if there were other predictors, like if people are able to imagine what their consequences mean, and something like if people experience monetary scarcity at some point, if that also influenced their decision?

29:42Yeah, totally true that we are so used about monetary information, but way less about carbon emissions. So, what we did in the instruction before the task, we gave some equivalence of the CO2 emission in terms of car journeys or days heating a flat or stuff like that, so that it's easier for the participant to understand what it means. But still, like during the task, obviously, it's easier for them to understand the monetary bonus than the carbon emission.

30:20But what we actually see is, like at one point, and they have some practice trial before, but at one point, the participant just realized that the trials go like from 20 to 100 kilos of CO2, so they kind of realize that the 100 is high and the 20 is low. So, but I think if you use the same task, but you just change the range, it's going to be the same, like they just kind of categorize, okay, that is high, that is low, and same for the bonus.

30:50And they are making this decision, and they are making this decision much more based on that than based on the absolute values. But obviously, I think if you have more expertise in what this CO2 emission means for you, like, even in everyday life, if someone tell you, oh, this emits x kilos of CO2, if you really know what this means, that's going to have much more meaning for you than someone who don't really realize what this actually represents.

31:23So, I think it's an important aspect, and there has been a few studies investigating this literacy, like environmental literacy, and like how you have knowledge about all this environmental aspect, and how this can actually influence your behaviors too. So, but we didn't control for that in our study, but we didn't control for that in our study, but we then use this equivalence in terms of CO2.

31:55Yeah, I think that's really nice, because when you first mentioned this is 120 kilograms of CO2, I was like, I have no idea what this means in a very practical sense. And that's why we give this equivalence, and then we ask them, how did you really understand all this instruction, and like they had to answer some questions to show that they really understood everything. Perfect.

Applying insights to the real world

32:23Yeah, that makes sense. And do you think it would help, like, if we try to apply this now to the real world, if people were more knowledgeable about what their CO2 emissions mean, and how much CO2 they're emitting when they do certain things? We can see that attention has kind of an influence of our decisions, so that means that the first thing to do is to provide information, because if you don't provide information, you cannot pay attention to them.

33:03And we are making decisions every day, and so we are not actually able to, all the time, think about what your decision means in terms of this, this, and this. So, if you provide information in front of the person, I don't know, like, when you have to decide for a meal in the restaurant, like, if you have all the information, I don't know if we need to add the CO2 of a meal in the restaurant, but it's just like, if you realize that your decision has an impact on the environment, because we don't think about that all the time, then you can then pay attention to this information and do something with it.

33:47And some people will do something with it more than other ones, but it's like a first step. And then we can maybe work on intervention, saying, okay, if I manipulate, not really, like, manipulate, but if I help people paying more attention to this information, how is it going to help a decision, like, pro-environmental decision, and does it work for everyone the same way? Like, like, like, it's kind of different step in the research.

34:18What we did with our research is more understanding, does attention play a role? How does it play a role? And then we can see how, when we kind of intervene on attention, how it can also have an impact on behavior. So, it's like the other step after. I'm now thinking about how you could add that information to, like, your everyday life. And my first thought was just add to the price tag, the tag below that basically gives you the CO2 emission of the product you're about to buy as distance you could drive in a car.

34:58Something that people can kind of imagine. And the problem is that also if you provide too many information to people, like, just too much, and they are not going to pay attention to that. And when you have, like, numbers, it's sometimes it's just too many numbers and it's kind of more difficult to process. And so, that's why also there is this eco-labels, like, also Nutri-score.

35:32So, like, it's much easier. You just use, like, three different colors. And it's much easier to process that when you are then making your decision. And so, there has been now a few studies about these eco-labels and see how it can influence, actually, the decision of the participant. Because you always want to add this information, but at the same time, you don't want to, yeah, you don't want to overload the participant, like, the individual with your decision with too many information.

36:08So, you have to find, yeah, the perfect balance.

Vegetarians and principled decisions

36:12Yeah, that makes sense. And in your research, you also study vegetarians and how they kind of do pro-environmental decision-making. And why do you think vegetarians are an interesting group to study in this context? Yeah, we wanted to do this study with vegetarians for different reasons. It's because, like, we know that the emission from our food system is, like, one third of all human global greenhouse gas emission.

36:54So, it's quite a lot. And when you look at this food-related emission, 80% come from meat and dairy products. So, that means that if you are vegetarian or even better vegan, your behavior has actually a huge impact in terms of emission, but also in terms of land use, water use, and so on. So, it's really, like, a high-impact behavior that you can have, that you can do.

37:26But the difference is there are also other behaviors like that. Like, for example, if you don't use, like, if you don't fly with a plan and you travel by train, that's also a very high-impact behavior. But the difference is that going on vacation with a train is a decision that you make, like, a few times a year, but that's it. But when you are vegetarians, that means that you are making this pro-emmental decision every day, like, every time you have to eat.

37:59And so, we thought that maybe vegetarians are kind of experts or at least, like, they have a routine in making pro-emmental behaviors. So, that's why we wanted to study this specific group because we thought that maybe we could learn something from how, like, what are the mechanisms behind pro-emmental behaviors by really investigating this group that are really used to do this kind of behaviors. So, that was the idea.

38:32And actually, we had a really nice result about that because we could see that vegetarian tend to make more pro-emmental decisions than the non-vegetarian. And actually, we were not even sure about that because we used, again, this same paradigm with the carbon emission and the bonus that they can get. And we were thinking that vegetarian will make more pro-emmental decisions because they tend to have higher environmental values and act like they tend to be vegetarian for environmental reasons.

39:11So, we saw, okay, they will also act more pro-emmental in this carbon emission task. But the opposite could be true because you could also feel like, okay, I'm already vegetarian. I think I've done my part. Like, it's enough to, like, contribute in the cause. So, maybe I will do, let's say, force in other behaviors. So, we wanted to all first look at that. And what we found is that vegetarian make more pro-emmental decisions, but we found very big difference between vegetarian and non-vegetarian when actually the decision involves very high cost.

39:50Like, when you had to decline a lot of money, then you really see a huge difference between the two groups. So, you see that vegetarian are much more willing to sacrifice their personal benefits for the environment. And you also see this big difference when the environmental benefits is quite low. So, when participants see that actually it's not making a big difference if I take the offer or not, you see that the vegetarian will still act for the environment, even if it's really low in terms of consequences and benefits.

40:32And another thing is that we see also that vegetarian tend to act more pro-emmental, even though they don't really think it's going to work. Because we ask them how efficient they think that this emission trading system is, because that's how we are going to then make this emission real. And even vegetarian who say, yeah, I don't really believe it's efficient, they still did it. So, they still went for the offer that's going to buy the CO2 certificates.

41:04So, I think that's really interesting because it kind of shows that non-vegetarian are more likely to, like, calculate the cost and benefits of each offer and see if I lose too much money or if the benefits for the environment is not that high, then I will go for the other option. So, like, you know, like, you don't really think, like, you don't really think, like, you don't really calculate the cost and benefits and you just go, like, you want to align with your values.

41:51It doesn't matter if it doesn't matter if it's really worth it or if you are going to have a high cost. And so, I think that was a really cool result to see this difference in terms of decision-making style. I think that's really, really interesting and I was wondering if you also investigated the reason why people are vegetarian in the first place and if there was, if that introduced any, like, variance because some people go vegetarian for the environment but some might also just do it for health reasons.

42:28Yeah, yeah, obviously, and so we looked at that, so we asked them what was the, like, the main reason why they became vegetarian and if the environment played, like, a pivotal role in becoming a vegetarian. And what we see is most of them have environmental reason or there is also animal welfare, but it's, like, the two main reasons for why they became vegetarians and that's the same in the literature.

43:00But what you see is that if we focus only on the vegetarian that are vegetarian for the environment, like, it's the first main reason, our result is even stronger. So, we see that we have even bigger difference with the non-vegetarians for all these aspects that I told you about. I think that's really cool. Yeah, I also found really interesting what you said about that vegetarians just seem to make more principled decisions because in the beginning, like, yeah, I'm vegetarian, so the reasoning with vegetarians make environmentally friendly decisions more frequently, that kind of felt wrong to me because it doesn't feel like I'm making a lot of decisions when I, I don't know, go to the supermarket.

43:53Or go to a restaurant and order food. It's just, like, that's my reality that I don't buy meat and I also rarely buy dairy products or something like that. It doesn't feel like I'm making these decisions all of the time, more like something that I've decided for myself and now I'm sticking to it. So, yeah, I can see this principle that I already apply in my daily life and that, yeah, I would probably also bring to a study like that. That would probably, yeah, make it easier to make even, like, disadvantageous, for me, disadvantageous decisions.

44:31But I think, like, you don't feel like you're making a decision all the time every day, like, regarding your food because you create some habits. And, like, if you think, okay, I'm fully vegetarian, you don't really have to think about it anymore. So, you don't have to, like, make deliberate decisions about that. But maybe at the beginning when you start being vegetarian, you start, like, it involves more deliberation in your decision than now. And so, obviously, it's not the same when, like, the vegetarian that we test, we knew that the decision that they will have to do with our task, it's, like, it's new.

45:12It's, like, they have to deliberate much more than in everyday life when they are making their decision regarding food. But it was more about maybe they, yeah, like, they have kind of a routine in this pro-evental behavior. So, maybe they will also quickly get this routine when doing the task.

45:33But, yeah, it's just an hypothesis. But that's also, like, we cannot make deliberate decisions all the time in our lives because that's, it's cost too much for our brain. Yeah, but it's interesting to think about it as a routine, like, making environmentally friendly decisions as a routine. Yeah, but, again, it's an hypothesis. I think for some vegetarian, it's way much easier than others to, like, decline non-vegetarian meal at the restaurant.

46:08Like, and that's why it's also really interesting to see, like, all the heterogeneity, even inside one group. But, so, I think it would be nice to go a bit deeper in this research about vegetarian. Like, it's just a first one, but I'm pretty sure it also depends on a lot of things. Like, how long you have been vegetarian? Like, oh, easy it is for you to resist meat. Like, some people, it's just, it disgusts them.

46:38So, maybe if you, every time it's an effort to be vegetarian, then all the parental decision, maybe you approach them in a different way. I think there is a lot of things to do with. We don't have all the answers yet. Like, yeah, I was just thinking, just before you said this, that I haven't eaten meat in so long. Like, it is in no way appealing to me, actually. Like, I find it more weird at this point.

47:12It's less of a decision and it's more like, yeah, it's not even on my mind as an option anymore. So, yeah, sometimes I realize when I watch, like, food content creators and they start cooking meat, I'm, like, so taken aback because it's so out of my reality.

47:32Like, my boyfriend also doesn't eat meat.

47:36I rarely see meat prepared. So, when I see it on the internet, I'm always like, oh, right, that's a thing people do. Yeah, but that's nice because, for me, there's been five years that I'm trying to be vegetarian as much as possible. And, like, every time at home, I never cook meat. But when I go outside or when I'm with friends, it's so difficult for me. Like, I really want meat. And sometimes I will take some. Like, it's really, like, it asks me a lot of inhibition to not take meat.

48:09And even though it has been more than five years. So, that's why I think it really depends from one person to the other. And there is much more to do. And I think if it's not, like, for vegetarian, maybe also, like, I don't know, when you travel, some people, for them, it's so difficult to not take the plane and go very far away. And for other people, it's just like, oh, no, I love going to France. So, I don't know. Like, it's not even a problem for them. So, it's not, like, with only one behavior that you can really see the commitment, like, the oriental commitment of one person.

48:42Because the cost is not the same for one person or the other.

Polluted nature and restorative effects

48:46Yeah, definitely. And in the beginning, you already told us that you were now involved in a research project which looks at participants in environmental settings and polluted environmental settings. Could you tell us a little bit more about that? So, firstly, why did you decide to look at that? And also, I'm very intrigued how you polluted the environmental settings and what you found.

49:23We had this idea because there is a lot of research on the benefits of nature. And, like, we know for sure now it's, like, we already knew with our cultural tradition and, like, it's, like, obvious for everyone that when you go to nature, in nature, it feels so good. Like, you feel better when you go in nature. But now there has been a lot of research also on that and which has shown that, actually, it's good for your affective functioning, your cognitive functioning.

49:54Like, there is a lot of benefits, not just, like, health benefits, but also, like, mental health benefits and well-being and so on. And so there is all this thing. But at the same time, like, nowadays we live in modern societies. There is more and more urbanization. So we have less and less access to nature, even though we know it's good for us. And there is also all this environmental degradation. So you have deforestation, you have wildfire, and you have all the litter.

50:29And so I think I had the idea of this study when I was doing a hike in my hometown. And, like, you have a big part of the hike that is in the nature and it's really nice. But then you have a certain part of the hike where you are in nature, but there is trash, like, all over the place. And I hope now the trash is gone. But when I went there, it's really, it was really difficult.

51:01And I had a really bad time when I was there. I was like, oh, that's not peaceful at all. Like, I could not, it was not, like, a restorative place for me. And so I was wondering, okay, what actually happened when you have this kind of environmental degradation? Do you then lose all the benefits of nature? And so we started this study, but we really wanted to do it in situ, like, in the field. Like, put participants in a forest or in front of a urban building, having a forest with litter or not, and see what happened.

51:35And because there is a lot of studies that just show pictures in a lab of nature or urban setting. And you already have effects. So that's huge because it's just with pictures. So that's, you can, and you know that you're going to have bigger effects when you do it in real. So we wanted to do that. And, again, we wanted to use eye tracking to see how, actually, nature can impact the way we pay attention to things. Because there is this theory, it's the attention restoration theory, which posits that when you are in nature, it's a restorative place.

52:15So it means that everything you look at is, it grabs your attention without any effort. So it's just, like, aesthetically very nice. And so you just pay attention to it without any efforts. And so that's what we call, like, involuntary attention or, like, effortless attention. And it's opposite to directed attention. So, for example, if you have to study, for example, an exam, or, like, you have to use all your directed attention.

52:47You have to focus on something. So it's not like, sometimes you can be really interested in the thing. So it grabs your attention for that. But if you are not that much interest, but you need to focus, then it's more like directed attention. And so the idea of this theory is that nature is only going to use your effortless attention. And so that gives some place for your directed attention to recover. So that's the whole idea of the attention restoration theory.

53:18And then there had been a few studies after that using eye tracking, which actually found that your eye movements are not the same when you are in nature or in urban settings. Because when you are in nature, you are making longer fixation and less fixation. And that might be because you don't, you're not paying attention to, like, it asks you less deliberation and efforts to just pay attention. So it's just slower and easier and that's on.

53:49And so the whole had this effect when they compared the urban building and, or, like, urban settings and nature. And so we wanted to do the same, but also with this degraded natural environment. Can I insert one small question here? So with eye tracking data, you can distinguish between the effortful attention and the effortless attention through the fixation duration and the amount of fixation points?

54:22Or how do you differentiate between these two attention types with eye tracking? It's like, it's not a direct measure of directed attention and effortless attention, but there has been a few interpretation in the past that actually, when you are making, like, longer fixation and less fixation, it's related to environment in which it, like, it asks you less directed attention.

54:56For example, if you are reading something, you need your directed attention and you are going to make a lot, a lot of small fixation. But if you are more, like, peaceful or meditating or stuff like that, you are going to make way, like, your eye movement activity is going to be much slower. So, but still, it's still, it's an interpretation of eye movement, but what they have found in previous studies is that every time in nature, the fixation are longer and less frequent than in urban setting.

55:31And so, you could interpret that as an index of directed attention or not, but it just, we had this effect. And then there has been other studies that show that after nature, you are better in a task, which with attentional, like your attentional performance are better after being in nature compared to urban setting. So, that's also how they connected this eye tracking measure with this theory.

56:03Okay, that makes sense. And so, yeah, for the litter, what we did, that was tricky because we wanted the participants to be in the same forest and not too far away from each other. And the forest was completely cleaned and that's really nice, a nice thing. And so, we wanted to put a few litter, but if we put too many, it would be just obvious that it is us that just did that. And so, the participant will know our hypothesis.

56:34So, we wanted to make it like credible for the participant and like, we wanted to make it like real so that they did not guess that it was actually us that did that. And so, we just put two pieces of litter. It was a plastic cup and a plastic bottle. But that was then quite subtle. And we actually had five participants who did not even notice the litter because we asked them at the end if they noticed or not.

57:09And so, we had a few who did not notice. And so, when we look at our result, we have huge difference between nature and urban settings in terms of attention. So, with the eye tracking measure, we see, again, this thing that fixation are longer and less frequent in the nature. We also looked at emotion and we had big difference. We see that in nature, it's increased better the positive effect, it decreased better the negative effect. It's also perceived as more restorative.

57:40And when we looked, when we compared the two forests, so the one that was cleaned and the one with a few liters, then we only had effects for negative effects. So, we can see that when there was this trash, so just the two plastic pieces, the participant decreased their negative effect less than when the forest is cleaned. So, that's already something because it was just two pieces of litter.

58:13So, you can imagine if it's more, like if it's an open dump, then it may be way, way worse. And so, it's like, I would love now to have a follow-up and just look if you add a bit more trash, what happens. Because here, it was quite subtle, but still with this subtle, like with these only two pieces of litter, we had effect on emotion. But we had no effect on attention. And that kind of makes sense because the whole scene was still the same.

58:48There is just like these two pieces of litter that were actually in the background. So, that is not supposed to affect the way you pay attention to everything else. Like your attention is not supposed to be impact. But for effect, that maybe that they see these two pieces of litter and it reminds them about like all their mental concern. Or it just reminds them that humans are not always paying respect to their environment.

59:20And so, that can like increase, I don't know, anger or sadness or irritability or stuff like that. But it had no effect either on the positive effect. So, that's like, it's still a good news that nature is so, has so much benefits that even if you degrade it with a few dishes, you still have a benefits effect. So, that's really good news for us. But I'm really wondering what happens when you have way worse degradation, like with deforestation or with wildfire.

59:56Like you, nature is still there, but it's completely destroyed. And when you know that it's related to human activities, how then do you perceive that? And how can this affect your, the nature of benefits? So, that's really a question that still needs to be studied a bit more. I'm also interested if you know anything about, so there are a lot of, I would say,

1:00:26partly urban, partly natural environments in the world, right? So, for example, a big park, but you can still see the houses around. Or you might walk outside the city, but you can still see the city, like, clearly visible in some distance. Do you know anything about our perception of these, let's call them, half urban, half natural spaces? Yeah, there is really a lot of studies on all this, and they already show that if you just go like in a urban green space,

1:01:04it's enough to have the benefits, specifically in terms of affective benefits. And so, that's really nice. And even, there has been a few studies that show that if you have plants, like indoor plants, that already help you with your affective functioning, cognitive functioning. So, that's already a really good thing. Like, since I started doing this study, I really don't see nature the same way.

1:01:35Like, I have a view on a park in my flat, and I try to look at it, like, the more I can, because I know that just that it's enough to feel better, like, to get the benefits of nature. And, of course, it's much better if you go to a full natural environment, but the more we preserve green space in cities, the better it's going to be for everyone, because we don't have all access to a full nature, like a full forest.

1:02:06So, it's really important to have a bit of nature, a bit everywhere.

1:02:11Nice. I'm now wondering, like, we have so little untouched nature in, like, I mainly know Germany, but I think this counts for a lot of Europe, that I think it would be really interesting to actually, to see if there is a difference in the restorative effects, if we go to, like, truly untouched nature versus the, like, the forests and fields that we have here

1:02:44that are close to the cities there that are influenced by humans. Like, when, I'm not sure if there's any place in Osnabrück where I live where you could see truly untouched nature. Like, the fields where I go for a run, they are there because people used them for, or used them in the past to feed animals.

1:03:09Yeah. But I know that maybe just, I don't know if it's just for forests, but when you have really, like, wild forests that are really dense, it can also be scary for some people. So then you lose a bit of the benefits compared to a more, like, domesticated forest. So it's funny to see that sometime when it has been touched by humans, it can still be better, but it's, I think it's specifically related to the feeling of security,

1:03:47and then maybe you can have that when you just look at the seaside or the ocean. And maybe the ocean is a bit more scary than just the sea, the beaches. I don't know. But, yeah.

Policy implications and co-benefits

1:04:00Yeah, that also makes sense. With this information that you gathered from these studies, especially the decision-making studies, how can these insights help us to understand why people make environmentally friendly decisions, and how can maybe policymakers use the knowledge to promote more environmentally friendly actions in society?

1:04:34I think this type of research is, like, a first step. Like, I don't know if with just this finding, you are able to, like, do policy intervention, but I think it can already help designing then more, like, intervention studies that will go, like, that is going to be a bit more applied, and then this could then help policymakers. But a few insights that we can already get from this finding is,

1:05:08like, for example, we can see that non-vegetarian individuals are more, like, doing this cost-benefit calculation, and so one way to help people to act more permanently could be just to show that when you act for the environment, actually there are more than benefits just for the environment. Like, if you show that there is a lot of different benefits, for example, you are vegetarian, so this is good for the environment,

1:05:40but this is also good for your health. This is, like, you can, this is good for animal welfare, and so on, so on. So you can show that there is a lot of benefits, and if you make people aware all the time of all these co-benefits, then the calculation of the cost and the benefits of these behaviors is going to be different, and so you're going to give more weight to all these benefits, and so maybe you're going to be more likely to then make the behaviors, and so maybe that's not going to change anything for, like,

1:06:13people who have a more, like, principled decision-making style, but for people who are more, like, calculating all these costs and benefits, then this could actually help. So I think that could be, like, a first lever for more parental decision. And, yeah, so as I told you, like, if we see that attention can actually play a role in parental decision, the first things to do is to help individual to actually have something about that

1:06:48that they can pay attention to, so that the information should be available, and then information should be easy to pay attention to, and that's already, like, a first step. But it's obviously not enough, but it's already one step, and then you can design some intervention based on that to see if it actually really helps, and if it helps certain groups of people and not other ones. Like, that's really interesting to see, like, to not think that everyone works in the same way,

1:07:22like, that people decide in the same way. I think there is a lot of heterogeneity, and that we need to pay close attention to this to have better intervention. Nice.

Cognition and takeaways

1:07:35And since we started out as a cognitive science podcast, so I think we've touched a lot on it, but just to make it clear, what role do you think cognition plays in your research?

1:07:52I think most of my research is really about cognition. I have also a bit about affect, but it's much more about cognition, and I think I'm mostly interested in attention. And obviously, it's not the only important cognitive processes. Also, like, I don't know, inhibition, self-control, it plays a key role in also parental behaviors. But I think attention is kind of one of the first steps to a decision,

1:08:23because an information that you did not pay attention to that is very unlikely to then be considered when making your decisions. First, you need to pay attention to something, and then maybe your decision is going to be based on this information that you pay attention to. So it's like the first step. And so I think it's an important aspect, but obviously it's not the only one. Nice. So if somebody has listened to this episode,

1:08:57what would you say are one or two of the most important things to take away from this?

1:09:06I think I would say that first, when we want to study the link between psychology and the environment, there is obviously how human behaviors impact the environment, so the pro-mental decision-making, and we can understand how this decision-making are made. But there is also the impact of the environment on human cognitive functioning and so on. And so that's another important aspect that you can study.

1:09:38And so, for example, being in nature can actually help your affective or cognitive functioning and degradation of this nature can also have an impact. So there are very different ways to study environmental psychology. I would say that also that attention, so the way we pay attention to information can play a role in our decisions. So it's important to actually have the information

1:10:11to be able to pay attention to. And that also, based on our attitude, on our dietary practice, or stuff like that, we don't make decisions the same way. And so that when we are studying pro-mental decision, we need to pay attention to all these individual factors so that we can really then design intervention and models

1:10:42that take into account this heterogeneity. So, yeah, I think I will summarize with that. Nice. Then, thank you so much for joining us today and thank you for being with us about your research. And for everybody listening, I'm just going to plug our own podcast a little bit. We also did a blog on attention where we discussed, for example, the effects of meditation on attention. So if you want to know more, you can also check out that.

1:11:15This was Kaleidoscience. We hope that you enjoyed this episode and we would love to have your feedback. You can rate our podcast and give us feedback on our Instagram account. Have a great week and you'll hear from us again in two weeks. This episode was hosted by Imogen Hüsing and Sophie Kühne. Produced by Imogen Hüsing, Clara Kühne, Sophie Kühne, Sönke Löw and Elisa Palmer. The music is from Jan-Huka Schröder and the logo is from Annika Richter.