Researchers at the University of Chicago have released a new study examining the impact of cities on human wellbeing, concluding that the socio-economic networks and active environments of large urban areas in the U.S. can result in lower rates of psychological depression.

The findings are part of a broader research project that aims to quantify and map what it feels like to live in a city, building on previous research that showed how people’s use of a city’s infrastructure networks can lead to increases in social interaction, innovation, and wealth production. “We wondered if those same principles and mathematical models could be applied to psychological phenomena, such as depression, to see if the actual social and infrastructure networks of cities—and how they change as cities get larger—could affect people's psychology in a consistent way,” said Andrew Stier, one of the study’s authors.

The research was developed as an extension of recent breakthroughs in urban science, which has built a consensus that people generally have more contacts across a greater variety of settings when they live in larger cities. Understanding that social isolation is a significant risk factor for depression, the team explored the idea that these varied networks could protect mental health. “It all fits to produce the main result of the paper: That the incidence of depression is actually lower on average in larger cities,” said research co-author Luís Bettencourt. “Not only that, but we can predict the quantitative magnitude of the effect based on bringing together the theory of urban networks with its effects on depression.”

While the latest study focuses on depression, it does not address other mental health conditions that may worsen with urban density and interaction. “What will be super interesting is if we can continue to identify the properties of larger cities that promote psychological benefits, while trying to eliminate some of the negatives of large urban living such as crime, poverty and inequality,” says research co-author Marc Berman. “Doing so might help us to have a more sustainable future, including better mental health.”

For translating the research findings into policy and action, the team suggests that resources for treating depression should be disproportionately allocated to smaller cities, combined with interventions in the urban environment to increase social interactions that occur more naturally in larger cities. “The problem is that because there is less population density over a smaller city’s infrastructure networks, people will have to travel more or coordinate their behavior more, to get an atypical increase in more diverse social interactions,” Berman explains.

To develop their research, the team aims to zoom closer into cities to examine how different neighborhoods can influence a resident’s risk of developing depression. This may encompass factors such as a person’s ability to move across the city from their neighborhood, which can influence social interaction, rates of innovation, and learning. The team is also interested in the psychological effects of other physical elements of cities, such as green spaces and parks, and how their distribution throughout a city is tied to psychological well-being.

“More generally, we are all interested in the link between urban environments, mental health, and cognition,” Bettencourt explains. “What characteristics of built environments contribute to better mental health? What helps people learn, collaborate, and take part in positive collective action? Mental health and cognition are the basis for agency and behavior, and urban environments do change how people think and act. This is an area of great promise as new data and methods in smaller populations become available.”