Stanford researchers found that walking in nature, as opposed to walking in urban areas, provides mental health benefits.

According to the study, led by Greg Bratman, a fourth year doctoral student in the School of Earth Sciences, after a 90-minute walk at the Dish, participants reported lower levels of rumination, which the study states is a known risk factor for mental illness. Participants also showed reduced neural activity in the subgenual prefrontal cortex, an area of the brain linked to negative emotions and mental illness risks. The participants walking along El Camino Real for the same amount of time, on the other hand, had neither of these benefits.

This summer, Bratman and his team are looking to further develop this study by replicating and validating the rumination finding and by finding other aspects of emotion regulation, along with an explanation of these benefits.

The research team also includes Gretchen Daily, Bing Professor in Environmental Science and senior fellow at the Stanford Woods Institute for the Environment. Daily is a founder of the Natural Capital Project, which uses studies like this one to integrate nature into the decision making of urban planners and the government.

“We’re trying to come up with rigorous and quantitative ways of bringing in the values of nature into our planning and investing,” Daily said. “We’re using mental health metrics to understand what the return would be, in some sense, in investing in nature.”

Bratman previously led a more general 50-minute walk study before focusing in on rumination for the 90-minute study. Other researchers had reported mood and memory benefits from nature, but the team wanted to focus on emotion regulation.

According to Bratman, three trends set the stage for the team’s investigation. First, over half the population lives in urban areas, and by 2050, the proportion is projected at 70 percent. Second, there has been a marked decrease in nature exposure and the opportunity to have nature experiences. Finally, there has been an uptick in mental health disorders globally, including anxiety disorders and depression. These are particularly pronounced in urban areas.

“We don’t know if these three trends are causal, or how they’re related,” Bratman said. “But they intersect, and that’s what we’re trying to explore by reintroducing nature to people who are deprived of it in urban settings.”

Though Stanford students have access to nature and hikes, other communities in more urbanized areas do not. The team hopes that this empirical evidence will prompt more care into integrating nature in cities.

“The actual design and planning of a city itself, in my mind, should incorporate attention to detail when it comes to parks and the layout of the city that allows people to bump up against nature in an easy way,” Bratman said.

So far, the subject pool has been urbanites and suburbanites and the team would like to see how these effects differ across people. For example, rural inhabitants may be saturated in their daily nature intake and not benefit the way their urban counterparts do. The researchers write that the positive effects come from the “soft fascination”, “sense of belonging” and “sense of being away” of natural environments. People already in a rural environment may not feel this “sense of being away”. Conversely, those who love city life may find some positive benefits in urban areas, an idea that requires more research in “pleasant urban settings” to see how they compare.

This study and related ones hope to spread awareness of nature’s connection to mental health and develop a deeper understanding for these benefits.

“I hope all of us help to inspire the movement that’s ongoing to start seeing our future as intimately linked to the prosperity of natural systems,” Daily said.

This summer, the team is bringing people into a more controlled environment to isolate specifics, such as noise, to identify the causes of these benefits. They will also look at how other interactions, including watching nature videos, could replicate the same effects.

“We’re just beginning to scratch the surface on the way nature helps us,” Bratman said.

Contact Alina Abidi at alinafabidi ‘at’ gmail.com.