Want to restore your attention span? Spend time outdoors

Walking in nature for as little as 15 to 20 minutes can improve your attention span — even if you don’t always enjoy it.

In his new 324-page book, “Nature and the Mind: The Science of How Nature Improves Cognitive, Physical, and Social Well-Being” (Simon & Schuster), environmental neuroscientist Marc G. Berman lays out how our natural environment can help restore people’s frazzled, overstimulated nervous systems.

Shelf Help is a wellness column where we interview researchers, thinkers and writers about their latest books — all with the aim of learning how to live a more complete life.

Berman, founder and director of the Environmental Neuroscience Laboratory at the University of Chicago, is also professor and chair of the department of psychology at the University of Chicago as well as co-director of the Masters of Computational Social Science program.

Through his lab’s research, Berman and his team have found that walking for longer periods of time — say about 50 minutes — can substantially boost cognitive function, but the beauty is you can still glean a noticeable cognitive benefit from spending just 15 to 20 minutes in nature.

Author Marc G. Berman

(Sadie Whitehead)

In one study, Berman and his team asked people to walk at different times of the year: in June when it was pleasant in Michigan and in January when it was 25 degrees and the trees were bare. As you might have guessed, the summer group was blissfully happy, and the winter group did not enjoy their stroll.

“But they still showed the same cognitive benefit as the people that walked in June,” he said of the latter group. “For these cognitive benefits, it’s not about liking the interaction. It’s something deeper. It’s how we process natural stimulation.”

(Simon Element / Simon & Schuster)

The Times spoke to Berman about what he and others have discovered through studying how our natural environments affect the human psyche and how we could design more elements of nature into our cities to improve our overall well-being.

This interview has been condensed and edited for clarity.

What is environmental neuroscience? Where did that term come from?

It’s built off some earlier research where people did studies on rodents and found out that when rodents lived in rich environments that had toys and there were other rodents around, these rats had more synapses in their brain, more glia cells. The physical environment that these rodents were [living] in was impacting their brains. And I was really taken by that.

[Then] I took this course with professor Steve Kaplan, and he was talking about this theory called attention restoration theory and how people could restore their attention by interacting with natural environments. Steve, an advisor and I designed studies to test attention restoration theory, and I saw in the field there wasn’t really a place necessarily for this kind of research.

All these studies on rodents were done years ago, and nothing was really tying it together. I saw all these different connections, and I thought, maybe I could help to define this new field of environmental neuroscience where we’d actually really see how the physical environment that surrounds us actually affects brain functioning and to try to combine cutting-edge techniques in cognitive neuroscience with ideas from environmental psychology.

Can you talk about these terms you use in the book: “involuntary attention” and “soft fascination”? It seems like what you’re saying is, when we are in nature, it has a way of recharging us because of the way we’re dispensing our brain space or energy.

[Let’s] start with attention restoration theory. One of the key tenets that was posited by Steve Kaplan and his wife, Rachel Kaplan, is that humans have two kinds of attention. One kind of attention is called directed attention. Sometimes that’s called endogenous or top-down attention. That’s the kind of attention where you as the individual person are deciding what to pay attention to. So presumably you’re deciding to pay attention to me and what I’m saying, even if it might not be the most interesting thing that you could find in the environment.

I do find what you’re saying interesting, just to be clear.

[Laughs] Humans are really good at directing their attention, but we can only direct our attention for so long before we become mentally fatigued, and it’s hard to focus. We’ve all had that sensation at the end of a long workday where you might be just staring at the computer screen and, you know, nothing’s happening.

When you can’t focus anymore, like that, we say that you’re in a directed attention fatigue state. You’ve exhausted this directed attention resource.

That’s different from involuntary attention, which is when our attention is automatically captured by interesting stimulation in the environment. Bright lights, loud noises, those kinds of stimulation automatically capture our attention, and we don’t really have any control over it.

Like the loud buzz of a motorcycle.

Yes, and it’s thought that that kind of attention is less susceptible to fatigue or depletion. So, you don’t often hear people say, ‘Oh, I can’t look at that beautiful waterfall anymore. It’s just too interesting to look at. I’m too tired.’ One of the ideas with attention restoration theory is that if you can find environments that don’t place a lot of demands on your directed attention while simultaneously having interesting stimulation that activates the involuntary attention, you could restore or replenish [your] directed attention.

OK, what would be an example of that?

We say that the kind of stimulation that activates involuntary attention has to be what we call “softly fascinating.”

When you look at that waterfall, it doesn’t capture all of your attentional resources. You can still mind-wander and think about other things while you’re looking at the waterfall. If you’re in Times Square, it’s also super interesting. It captures a lot of your attentional focus, but it does so in an all-consuming way.

The kind of stimulation that gives you this restful, restorative experience has to be softly fascinating and not harshly fascinating.

In the book, you write quite a bit about the curving design of nature and its benefits. For the cynics among us, I wanted to ask: Can we just design more nature around us and more of its elements into buildings and benefit without actually being in nature — without taking a walk in the park or in the woods? Is it just curves that we need?

We can get some of the benefits that way. Antoni Gaudí and other architects knew that in how they designed buildings, and people really like those kinds of buildings that have biophilic design, where they mimic the patterns of nature in design. I don’t view that as a replacement for nature. That’s sort of like a supplement.

We find that in a lot of our studies, going into actual nature gives you the biggest bang for your buck, because being in nature, you get all the modalities: the visual, the auditory, the tactile, even the olfactory, the smell. You’re getting that whole kind of experience that I think you just can’t really mimic in a built space.

I wouldn’t want to say, “Oh, the takeaway is, if we found all the nature ingredients, we can destroy all the nature and then just build it.” No, we have to preserve all the nature, because we can’t engineer anything as good as nature.

(Maggie Chiang / For The Times)

You write about the benefits of experiencing nature when one is depressed, anxious or grieving. What is it about nature that helps the anxious or depressed mind? Is it that we are finally putting our phones away?

We’ve done studies with people who have been diagnosed with clinical depression and we weren’t actually sure if the nature walk would be as beneficial to them.

We thought, “Well, if nature increases attention and cognitive abilities and if somebody is suffering from depression and they’re ruminating about negative thoughts and feelings, maybe a walk alone in nature might actually increase depression and increase depressive rumination.”

We did the same walking study [with] a nonclinical sample. But with these participants with clinical depression, we actually induced them to ruminate about negative thoughts and feelings before they went on the walk. And we found that the walk in nature was actually more beneficial to participants suffering from clinical depression than it was for our nonclinical samples.

We think that’s because when you are in a depressive state and you’re ruminating about negative thoughts and feelings, that’s actually robbing a lot of your attentional focus and your directed attention. So nature is boosting them up, and we think that is giving them the cognitive resources to then deal with their depression and their rumination.

In the book, you talk about how nature can make us see each other again as people. How do we, and especially parents worried about their kids growing up in this sort of dehumanizing culture that we’re in, tap into that benefit?

There was a study done by some researchers from China where they found that being in nature, you’re not so egocentric. You feel like you’re part of something larger. And then that actually increases feeling of humanization of others. Even though there may not be people out there, you start feeling more connected to everybody, in part probably because you’re feeling more connected to nature.

And they found this could even happen with indoor plants, which they found increased feelings of humanization of others and self-transcendence. And it wasn’t just driven by nature making people feel good. It was about nature increasing these feelings of self-transcendence, and then that increased feelings of humanization.

You and I have both said “in nature” multiple times. How do you define “in nature”? Like, what’s the baseline for when our brain says, “I am in nature”?

It’s a hard thing to define. It probably differs for different people, like your dad‘s definition of nature [in Oklahoma] might differ from somebody living in New York or Los Angeles.

What does one person conceive as natural that another does not? What does appear to be very consistent across cultures is this nature preference — that people do prefer things that look more natural to things that look more built.

How important is it, in terms of benefits of being in nature, that nature inspires awe? A walk in nature through a park that your average person would perceive as boring — does that benefit them?

You don’t have to be going to the most awe-inspiring beautiful nature to get these cognitive benefits. But if the nature is so boring, like, I don’t think you would get a benefit like walking through a cornfield per se. And we’ve actually asked people, “Do you like the cornfield more or walking through a tree-lined urban street?” And people like the tree-lined urban street better than the cornfield. You might argue maybe the cornfield is actually less natural than the tree-lined street because it’s been so influenced by humans. But it’s just to say that not all nature is created equal, and not all urban is created equal.