(Unedited) Podcast Transcript 580: Community Severance by Road

This week on the Talking Headways podcast we’re joined by Jaime Benavides and Marianthi-Anna Kioumourtzoglou of Brown University to discuss their new paper showing how community severance by road infrastructure and traffic has led to more mental health related hospital visits in New York City. We talk about the role of roads cutting people off from social connections and how impacts of roads on mental health were separated out from air quality.

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Below is a full AI generated unedited transcript of the episode:

We had a lot of fun, and then I went to New York from Spain to work with Marianthi to gotten into the health side of things. I’m very curious, uh, very enthusiastic about cities, environment, and health.

A lot of the folks who come on the show, they’re, you know, transportation planners or urban planners or scientists of all sorts. I’m always interested how people get interested in the science that they’re interested in.

My mom used to say, “You don’t even know what that is.” Neither of my parents are in the field, right? “So why do you want to do this?” And I don’t have an answer for that. But then I didn’t get to into med school, which was great. Best thing, luckiest thing ever. I went to environmental engineering school instead, and I kept thinking throughout engineering school in Greece is five years.

For five years I kept thinking, “But is the only reason we care about the environment human health?” Which is, I know it’s very simplistic and, uh, reductionist, but then I really wanted to study the impacts of the environment on health, and because of my background, I don’t understand what’s happening in the, in the human body, inside the human body.

So I study the external environment, and that’s weather and air pollution, and 80% of people in the US live in cities. That’s the urban form, which is something we are all exposed to and can have really detrimental but also amazing impact on our lives and our health. So understanding what the bads are to try and minimize those and what the goods are to try and amplify those, I think is very exciting for me

And I, I wanted to learn how to conduct the kind of studies that link both, like, the environment and health outcomes in cities.

Can you tell us about the work a little bit and what you found?

At the same time, we do see in the Western world, and in general, a huge shift towards, not so much recently with the current administration, but in general the past years, stricter regulations on emissions and moving towards electrified fleets. So that, in theory, would mean that air pollution goes down.

However, we are still left with these huge highways, and the entire infrastructure that was built, especially in the US, that most of it was built after the car, and so for the car. And so Jaime was very interested in understanding the role of the infrastructure itself. Like let’s say you substitute 100 of gasoline or diesel cars with electric cars, so zero air pollution, zero noise.

Is our health getting infinitely better? There are no issues there? So he came to me, and he wanted to figure out how to quantify that infrastructure, road infrastructure for health studies. So we sat together. We had several meetings trying to figure out how to do it, and we came up with a way. So this is a concept that originated in sociology, community severance.

And community severance captures conceptually how road infrastructure, motorized traffic, sever, break down communities. So that means harder access, less access to services and goods, reduced social cohesion, et cetera. And so we sat down and figured out a way to systematically quantify community severance in New York City.

And then that’s the first piece of the puzzle. And then we’re both independently interested in mental health outcomes in our research. And there is a lot of background saying that many mental health outcomes have higher prevalence in urban cores. So if we have severed communities, and part of what these do are increase isolation, and then at the same time we have increased prevalence of many mental health outcomes in cities, like it was actually surprising that people hadn’t tried to look at these two together.

So that’s what the paper Benavides is about. We tried to examine… In New York City, so it’s a case study on New York City. We tried to examine how community severance, that is the quantification of road infrastructure and motorized traffic that breaks down communities, what’s the impact of, of that on mental health hospitalizations.

And right after that, I got to New York City. I used to see like these… We now have everywhere SUVs, right? Also in Europe, like… But all those huge vehicles and all the trucks going through the center of the city, and I don’t see that the humans are the, the same height, right? Like, so also for kids, you know?

So when you are comparing the height of a kid compared to the huge truck or the big SUVs, for sure that has an impact on this person’s life beyond air pollution or the noise, right? Which is a lot. But the fact that the physical presence of roads and traffic, like instead of something else, instead of a park or a square or just like a very boring street, but, uh, with no machines, huge machines that could threaten life, right?

So that, that was like the first observation, but this is that connection between- In COVID, this awareness of how important is space for everyone connecting with the curiosity of what is happening in the brain when we are exposed to these machines, and then all the scientific literature from the s- ’70s saying things like in very busy streets with a lot of traffic, people tend to have less social connections with their neighbors.

Also interviewing, like asking families, like, “No, my kids don’t play in the street because it’s very dangerous, so they are stressed at home, and they are playing video games,” and things like that, uh, brought us to, to also try and understand what’s going on

The traffic-related air pollution, which has been shown to have impacts, right, on things like Alzheimer’s and dementia and other brain health things. And so you mentioned a little bit, Jaime, but I wonder what made you look past the air quality impacts and, like, laser in on this specific thing that was the traffic and the connections that people are severed from.

Like, there is a lack of understanding of if we occupy all that open space with, again, huge volumes moving very fast of these machines, like, is that good or bad for our mental health? So yeah, it, it was, as Marianthi said, from my perspective at least, looking beyond air pollution and imagining, like, if the city will have still the same levels of noise and air pollution but had another use of space, would it be more healthy or not?

We don’t necessarily see the regulations following in the rate that I would have wanted to protect human health. And so how can we then figure out modifiable, intervenable pathways so communities can protect their residents? And the urban form is one such intervenable pathway. That’s part of it. The other big part of it is, okay, as we are electrifying our fleet, I will keep saying that the cons of car dependency are not only noise and air pollution, it’s that it’s lack of physical activity, it’s lack of, of social cohesion and in-person social cohesion.

It’s very interesting. Parentheses, we were talking with a colleague of ours who’s from Texas, and Jaime and I both grew up in Europe in very dense, uh, not car -oriented societies, or not so much at least. And our colleague from Texas was saying, “But it’s so easy. I get into my car, in 10 minutes I, I can go and see my brother.

What are you talking about isolation?” And so- Mm-hmm … like, that’s disconnect there because it’s, okay, you are more connected to a family member, but you’re not necessarily connected to our neighbors. Neither of us lives in New York anymore, but we used to live in… I did not know any of my neighbors in the buildings I was living in.

Maybe that’s on me. But, but, but I, I think that’s a general trend, right? We don’t know our immediate community, and there’s so much work on the benefits of both physical activity. Even if I have to walk for five minutes to go get a bus, that’s five minutes more than, you know, garage door and driving, right, door to door.

If you have the plaza as, as Jaime said, you go there, you interact with the people more. People check in on you. So that’s beyond just removing the air pollution from the equation. There are so many other benefits from reshaping our immediate environment outside of the house to help us build healthier lives that I think we haven’t looked as much, or at least in environmental epidemiology, other fields probably have, but as much into.

Thanks. So when we started talking, when Jaime came up with the idea of looking at community severance and mental health and came to me and said, “I want to do this,” and we had the hospitalization data for mental health, my main concern was exactly because of the very big literature on the air pollution impacts on mental health.

My concern was, okay, but if we publish this as is, everybody will just say, “Okay, then it’s just all through air pollution.” Obviously, what you’re capturing is air pollution, so we wanted to see is it all air pollution, or if we could somehow block the air pollution effect, do we still see impacts? So we used black carbon predictions.

Black carbon is a combustion byproduct that is usually associated with traffic in urban cores. And the New York City has an amazing program, um, NYCAS, that has multiple rotating… The number of monitoring sites varies from year. I think it goes from 60 something to 100 something. But they rotate these, and they then integrate these with land use data and traffic data and all other kinds of data to build these pretty high resolution, 300 meter predicted annual surfaces for different pollutants.

Black carbon is one of them. And so we then included black carbon in our model, hoping to block the path from community severance to mental health From air pollution. So we said, okay, if we compare now two communities to zip code levels that have the same air pollution, but different community severance, do we see differences in mental health outcomes?

And indeed, what we saw was, as expected, once we added air pollution into the model, our effect estimates attenuated a little bit, became somewhat smaller in magnitude. But importantly, they didn’t completely disappear, which does mean that, yes, air pollution explains some of the effects that we saw, but not everything.

So even if we take out… So community severance doesn’t solely act through air pollution to induce the increased rates in mental health hospitalizations that we saw. And I keep saying mental health hospitalizations. We examined multiple causes, but our biggest finding was on schizophrenia hospitalizations, actually.

So it’s not all of it through air pollution, but there are some other pathways, we don’t know exactly how yet, that’s to be, you know, next studies, future studies, but that not through air pollution, that community severance results in higher rates for these mental health hospitalization rates.

So yeah, le- the less socially cohesive the neighborhood, the more isolated this community are, who are already kind of isolated because of the disorder.

Mm-hmm. So maybe community severance is one of the reasons contributing to that. But that pattern has been reported way before our, our studies.

But it’s interesting you all were able to tie it together.

So that’s more of an exacerbation our study. It doesn’t mean that the relationship with onset is not there, but our study was not able to look at that.

It causes all these problems, et cetera, et cetera, right? Mm-hmm. It’s ridiculous because of all the benefits of cities that we know, uh, socially, et cetera. But I’m curious, like, more about that and the connections that people, and sometimes the media and sometimes others wanna make about the mental health and the connection it has with cities specifically.

But I think the question is, how do we reshape our cities in a way that ensures that the population lives the healthiest they can live, both in physical and mental wellbeing? Cities are living organisms in some sense, right? They evolve over time, and they change, and we have the opportunity even though we right now get the cities as they are, we as residents have the responsibility to make sure to ask for our cities to help protect our health, and that’s choosing whom to vote, showing up in community meetings.

That’s how we are all involved into reshaping our living environments that play such a big role in our lives that we don’t though necessarily realize. We take it for granted. This is how it is. Like, this is New York. Take it or leave it, like, right? Or this is Providence now that I live in, and it doesn’t have to be that way.

It can be 100 times better. We just need to try a little… It’s not even try so much more. We just need to try a little bit more and, you know, take a lane out for traffic and put some trees in, right? It’s not that hard, and it makes such a big difference. I say it’s not that hard. I also occasionally believe that cars should be banned outside from downtown centers.

So, you know, that’s controversial, controversial,

um- Probably not with our listeners, but yeah.

Yes.

My dad used to run to school from home. Uh, it would take him, like, four or five minutes, and he would sprint to get there by himself at age, like, eight, nine years old. And there were some cars, but there were not that many. And so if in our generation and previous generation, we allowed this change that we know that it’s not that healthy, and we are the last to know the people who were able to run in the streets, to play in the street, to play with other kids, and their families would meet in the street.

That’s a, a knowledge and a culture that if we like it, i- if we want it to survive, we need to, to work to make it happen, right? Otherwise, in two, three generations, it will be gone. Right? It will be in the history books. Like, “Ah, well, we had kids who would play in the streets,” but we will have no one who has ever done it

Like, how did you calculate it, first off, and then, like, what does it tell you specifically?

But, you know, like, to create equations that then explain the physical presence of roads and traffic, and Marianthi would stop me and say, like, “Jaime, how many assumptions we are gonna need to make in order to build those equations that then they might not be even relevant? Because, like, how, how do we create all of that?

Like, uh, why don’t we interrogate the data, uh, that we already have for, for New York City, and try to learn what are the main patterns that we can find in the data?” And of course, we will have our hypothesis that if what we learn from the data, the main patterns, is aligned with this community severance concept, then we could use its scores, so the, the kind of the value of this indicator in each area, you know, in each census block group, as the community severance index.

Otherwise, we will not be able to use it. And, uh, Marianthi and colleagues had been kind of adapting an algorithm from computer vision for pattern recognition, uh, so to recognize, learn patterns from data based on… And it was coming from, like, video surveillance, and they adapted it to environmental health kind of data sets.

So I was there. Like, it was the moment to use it, so we had to decide what kind of information put into these kind of ingredients, right? Like, the, the ingredients of the cocktail that we are gonna use to then run this pattern identification algorithm and then see what are the main patterns that this process get.

It was tough to decide what kind of information to add, and we ended up with three main categories of information. We, uh, used information on road infrastructure Things like road density, you know, like how prevalent is the road in this area, or also a road traffic activity, like volume, like number of cars going through a street.

Uh, but also we included pedestrian infrastructure because we thought, like, then when we try to interpret the patterns that we get, if everything is talking about traffic, we may get like, yeah, there is a lot of traffic as a pattern, but then we would not have information on are we able to walk there? Are there sidewalks?

Uh, is there pedestrian infrastructure? So we also added a category on pedestrian infrastructure, data like the National Walkability Index or also, uh, the density of pedestrian infrastructure And we put them in this algorithm to identify patterns. And what we learned that there was a, like a main pattern that explain most of the information in New York City.

New York City, thankfully, is a, like a very diverse city. It has like parts of the city which have like huge roads and mainly car dominated, but also there are other areas that are very walkable. So the main pattern identified areas that explain a lot of the, uh, variability in the data by three quarters, like 70% of the variability of the data.

And it had traffic, like road infrastructure and also traffic activity loading in one direction, and then in the other direction we had a pedestrian infrastructure. So this thing of one direction and the other direction is kind of related to the score of that index would be very correlated with traffic.

So high values of the score would only take place when we have a lot of traffic and road infrastructure, and the opposite with pedestrian infrastructure, right? Like when we have a lot of this indicator, it would mean that pedestrian infrastructure there is very low. The presence of pedestrian infrastructure.

And so the more stressors you have, the redder the map gets, right? And so I’m interested in those types of things because we’ve– I’ve used them before. But also just like thinking about if you have these barriers like traffic and roads that concentrate these specific stressors even more, you get these negative impacts, and they kind of compound on each other.

And so I’m fascinating how this aggregates with a number of other different like data sources where you can tell people, “Hey, we understand that this specific zip code or this specific block group or whatever the geography is, has issues or there’s more prevalence of schizophrenia.” And why is that? You know, when you look at the traffic patterns, when you look at like the amount that people can or can’t get out of their neighborhood.

And I just find that fascinating to make those connections between environmental justice and the things that we know just like intuitively are an issue, but now you can calculate them.

Highways are not randomly distributed In the population, they like the example of Robert Moses in New York City again, right? They were on purpose placed in certain location, displacing certain populations. So there’s this structural element that inherently binds community severance with a lot of other environmental justice issues that we see, and a big part of it is historically structural.

And you are right, if you have community severance, that means you have cars, that means you have higher air pollution. That means you by definition have a lot more asphalt that gets much hotter during heat waves. That means you don’t have a lot of green space to reduce the heat, give shadow, give opportunities for physical activities.

That means you have more flooding because you don’t have the soil to… Right? All these things compound on another, and then you add isolation and broken down social cohesion and all that. So as you said, this, if you think about it, kind of all makes sense, and we are just starting to quantify the community severance role.

Like there’s a lot of work in environmental justice, so I’m not saying we’re, we are starting that by any means, right? But we’re not just trying to figure out the role of community severance in environmental justice

And so thinking about humans as animals, right? That mountain

lion in LA a couple of years back,

right? Yeah, exactly. Yeah, he talks about that, the lack of genetic diversity, and so the, the mountain lion had problems with his genetics that he couldn’t pass along because he was stuck in this circle of highways that he randomly crossed.

And so I, I just think about the connections there, ’cause humans, we are animals as well, and so these roads are not just, uh, impacting the migratory patterns of elk or anything along those lines, salamanders or whatever it might be. You know, the roads are impacting our social cohesion as well, and so I find that kind of a, an interesting connection.

It also impacts people’s, you know, social connections to their community. I mean, we also had Dr. Mindy Fullilove on the show to talk about her books and, and one of her most popular books, Root Shock, talks about if you remove a human from their community, what happens to them, right? And so I feel like this is not just removing people, it’s actually, like, penning them in, and this is a kind of a, a, a metric to show how, how the penning happens.

Exactly.

I don’t… I stop myself thinking that how we build a city is changing drastically that in the last five, 10 years because cities didn’t change that much. Things like the social networks, mobile phones, like, like how we are… Uh, everyone, like, losing our ability to concentrate or to focus, and especially for adolescents.

Like, what I would suggest in that concern related to mental health is that- Cities could be places that are more competitive against these social networks, um, video games, like, that potentially they could bring more interest and attention to these young generations than we lead, like city changes. So for sure it has an impact also in their lives, a negative impact.

This, for example, community severance, we haven’t studied that yet, but it may have, uh, also an impact. But I think in the positive side of things it could be very beneficial also to them. If cities are more fun, more attractive, they… We can all enjoy more our street and the neighbor’s street, uh, so people may tend not to spend that much time looking at a screen, right?

And so-

So I, I find that really fascinating.

And I’ll add here that it does also build healthier habits if the kid has to walk. Like, I don’t know how many kids today walk to places because they have to be driven, right? So it’s, it’s very different from having to walk to my soccer practice or having to walk to whatever after-school activities I have.

There is the issue of safety. Is it safe even if I can actually do it? So that’s a whole other issue. But I think it builds an, a general healthier- habit that hopefully stays afterwards. Whereas if you grow up driving everywhere, then all of a sudden if things change, then that’s weird, right? You cannot just all of a sudden decide, “Yeah, I’ll walk 10 minutes to take a bus for the first time when I’m 45.”

Another thing, like n- not just kids, but, like, older adults too. I mean, in the report you talk about people 65 and o- over, and I think with our silver tsunami that’s coming here, at least in the United States, I mean, there’s the baby boomer generation is aging into that cohort. And so there’s all kinds of risks of people getting stuck at their homes, losing their social connection, social isolation.

I mean, this is all over the world as well. Y- they talk about, a lot about it in the UK, I know specifically about social isolation and, and fixing those problems. But this is an issue that you had talked about in the report as well, is the older than 65 and the groups that are aging into that cohort.

One, I absolutely agree with you. I say this is a sample size of one. It’s my grandmother. In the winter, she’s in the city with my mom. In the summer, she goes in the village. Completely different person. She’s 94 now, 93, 94, and she’s starting to have some dementia or cognitive decline. And the change, like the drop in the city, that she cannot see people, she cannot go outside herself, right?

Versus in the village in the summer that she goes, she’s out in the garden, people can visit her, she can visit people. She has many more interactions. Ag- again, one person, we cannot generalize that it will be beneficial for everyone, but the change is so drastic. In our study, we did look at people below and above 65.

Unfortunately, hospitalizations for mental health disorders among people older than 65 are not that very common, so we did not have large enough numbers. So for some of the outcomes, and Jaime, correct me please if I mess this up, it was for mood and adjustment disorders. We did see that the point estimates were larger among those who are older than 65, but they were very imprecise.

So we would need a larger study to be able to better quantify those effects, or ideally not hospitalizations. We would probably need to have symptoms, data on symptoms or things like that to be able to capture… Because hospitalization capture the most severe cases. Mm-hmm. But if I have a flare of depressive symptoms, I won’t necessarily be hospitalized, right?

So I think we’re missing that, and that would have made even more of a difference when looking at age groups.

This would only increase your psychosocial stress, how stressed you feel, your cortisol levels. So that then has downstream, uh, consequences.

So it’s also difficult to differentiate between both of them.

It also connects to me like the ideas, and we’ve talked about these on the, on the show a bunch, is like transport insecurity and food insecurity and the connections between being able to access things, whether that’s people or places or healthcare or whatever it is, or food for that matter.

Um, and then food is, is health, uh, in its own right, and so the connections that can be made. And so a lot of the insecurity research is showing that, you know, a lot of the problem is because there’s not a connection. It’s disconnected. People are disconnected from these things, whether that’s grocery stores are too far away, or you’re required to drive and you don’t have a car, and so you feel ashamed or embarrassed to ask for help or a ride.

Those things can add, I feel like, a piece to this as well.

And it’s not only food, but it’s also healthy food, right? Because you may have access, if you live in between highways, you probably have access to a lot of junk food, but that only promotes mental health issues because of the connection of nutrients and mental health. So it’s not just accessing any food, but especially healthy food that tends to concentrate in, unfortunately, different areas than, you know, highway crossings.

You’re absolutely right about that, yes. Anecdotally, New York City had this amazing program of having fruit stands in healthy food deserts. And I think, I’m not sure about what I’ll say, but I think they haven’t changed those in a while, where those are. And I used to live in Battery Park City, and I had a Whole Foods right there, and I had a healthy fruit stand right across the Whole Foods which was so, like, it didn’t make any sense.

And there are entire parts of the city… And if you see behind those maps, community severance there is very low to near zero because it’s all very nice and walkable. And then if you see other parts of the city with high community severance, then they have zero access to any healthy foods, and that’s not okay.

Like, that’s… We talked about compounding things earlier. Mm-hmm. That’s exactly what that is.

And it wasn’t. And for me, that was … Jaime, sorry, I don’t think I’ve ever told you this, but to me, that was the most eye-opening moment. For me, that was the wow moment

I’ve been exposed to mental health issues, and it’s so convoluted, and it gets more and more convoluted, and it’s that difficult to ameliorate or to change things. So then what I thought was like, “I don’t think this is gonna have much connection.” Like, so I, I do see why we need to study this. It’s potentially important, but there are so, so many things that are important, like poverty, right?

Or like how the social environment is, or trauma, or also nutrition, like many, many, many other things, right? Like, so community severance, I don’t think it’s gonna have any association. Uh, we are not gonna see anything. And then when we saw this signal, and we were adjusting by all those other factors that we thought that had a connection with mental health, but still we would see some link between community severance and mental health, that was for me the wow, yeah, there, there is something here.

But it’s something that, you know, the social isolation, the impacts to, to health. I mean, we’ve talked with a number of folks about mental health, about physical health, about the connections between transportation and policy and all those things. And so when I read the piece in the Brown news site, I was like, “Oh, well, this is new.

This is interesting,” because it’s different, and it’s not necessarily air pollution that is the specific tie, even though it’s still a part of it, obviously. But it was really fascinating to see you all do this research and come out with something that was new and novel and exciting.

And I will say the fixes don’t have to be really, we don’t have to just start taking down highways. That’d be great, but that’s not realistic, right? But Jaime and I have gotten into a habit when we’re in places that are very clearly severed, we send each other photos. And I was in a neighborhood in New York City once.

There was a highway, but it was elevated, and there were just- Random cars parked right beneath it. It was hard to cross. It was… And all that, it’s space that could be so much better used for the community. The space is there. We don’t have to take the, over the highway necessarily, but that space, and there’s so many spaces across the country like that, could be repurposed for community purposes.

So small starts, small steps. We don’t have to necessarily, okay, you know, burn all your ca- don’t burn, air pollution, but- … you know, get somehow rid of all of your cars. But there are, there are small steps that we can start with to see how that much improves our lives.

But we are also concerned that the conception of community, uh, how do we get to our communities, uh, across the country in different cities and the different areas of the city change as well. But yeah, working more on this and learning, learning from different cities, different places. It would be great to collaborate with people from different cities that we don’t know and go there and interview people and put together the, some data, uh, work on it.

And also look on, on the mental health side of things, um, potentially look at also other environmental exposures, like what happens when you have, like, a lot of heat, you know, like very, very high temperature, extreme temperature, and also you have community severance. It could, like, all the people reach the grocery store or do they have enough visits, like things like that.

Do they get more stress? Do they use the street? Do they find the shade? Yeah, things like that. But in general, to try to contribute and make healthier the places where we live.

So, uh, Jaime now is working, for example, on a paper looking at community severance and access to green spaces. So that’s an immediate next step or concurrent step, I guess. But so that’s a very important first step, but also importantly, how can we design our studies in a way that actually provide helpful information to communities to reshape, right?

Okay, we published this, but it’s not like a community can say, “Okay, let’s do some-” Like what, what?

Yeah.

So how can we then redesign studies to identify community level actually and easily, feasibly modifiable factors? So the first step is characterize. The next step is- And now how do we do this? But as Jaime said, that will require also some expertise and experience in serving people, because how they perceive and experience might be very different what, you know, what a data point might say- Mm

in a spreadsheet.

For

sure. So I think that would be very important as well.

Yeah, exactly. So, uh, we are at Brown University. Our emails are [email protected], and mine is [email protected].

But apparently if you just Google Marianthi Kyriazoglou, there you go, uh, you can find me.