Good news makes me nervous.
More precisely: if I want to believe a research finding, I become very suspicious of it. After all: it’s easy to fool me when I want to be fooled.
Specifically: I’m an outdoors guy. I’ve worked at summer camps for ages, and love a good walk in the forests around Walden Pond.
So, when I read research showing that even a brief nature walk produces cognitive benefits, I’m both VERY EXCITED and EXTRA SKEPTICAL.
Let’s start with the assumption that it’s just not true.
Persuade Me
The research I’m speaking of is in fact a review article; it summarizes and compares the results of 14 studies. (The review article was flagged by Professor Dan Willingham, one of the leaders in translating science research for the classroom.)
These 14 studies shared important commonalities:
First: they looked at “one-time” exposure to nature. They didn’t look at — say — outdoor education programs. Instead, they looked at — say — a brisk walk in a park near the school.
Second: these “one-time exposures” were all relatively brief — somewhere between 10 and 90 minutes.
Third: these “brief, one-time exposures” did NOT deliberately focus the participants on nature. That is: students didn’t walk in the park to learn about trees and birds. They walked in the park to have the experience of walking in the park.
I might be skeptical about one study. I might be skeptical of two studies. But if 14 studies (or a substantial percentage of them) all reach the same conclusion … well, maybe I’ll be persuaded.
Equally interesting: these studies ran the K-16 gamut. We’re not looking at a narrow age-range here: more like two decades.
Conclusions (and Questions)
So, what did this potentially-persuasive bunch of studies show?
YES: in 12 of the 14 studies, brief, one-time, passive exposure to nature does benefit cognition.
More specifically, researchers found benefits in measures of directed attention and working memory.
They looked for, but did not find, benefits in measures of inhibition (another important executive function).
And, crucially, they did not measure academic performance. If a walk in nature enhances attention and working memory, we can reasonably predict that it will also improve learning. But: these studies did not measure that prediction.
Because this review covers so many studies, it’s easy to get lost in the details.
One point I do want to emphasize: the impressive variety of “exposures.”
Some students walked or played in a park, woods, or nature trail.
Some simply sat and read outdoors.
Amazingly, some walked on a treadmill watching a simulated nature trail on the monitor.
In fact, some simply sat in a classroom “with windows open on to green space.”
In other words: it doesn’t take much nature to get the benefits of nature.
Inevitable Caveats
First: in these studies, exposure to nature helped restore attention and working memory capacity that had been strained.
It did not somehow increase overall attention and WM capacity in an enduring way. Students recovered faster. But they didn’t end up with more of these capacities than they started with.
Second: most of these “exposures” included some modest physical activity.
How much (if any) of the benefit came from that physical exertion, instead of the greenery?
We don’t yet know.
A Skeptic Converted?
I have to say, I’m strongly swayed by this review.
In the past, I’ve seen studies that might contradict this set of conclusions.
But the number of studies, the variety of conditions, the variety of cognitive measures, and the range of ages all seem very encouraging.
Perhaps we can’t (yet) say that “research tells us” brief exposures to nature benefit students. But I feel much more comfortable speculating that this belief just might be true.
