An annotated, chart-filled look at the scientific evidence.
m01229 / Flickr
I’m not a doctor, but I do sit near one in The Atlantic’s New York office. So you can trust me to know that MD-in-residence James Hamblin is on to something when he writes in the magazine’s October issue about the rising appreciation among physicians for the health benefits of parks and green space. Hamblin writes of “a small but growing group of health-care professionals who are essentially medicalizing nature”:
At his office in Washington, D.C., Robert Zarr, a pediatrician, writes prescriptions for parks. He pulls out a prescription pad and scribbles instructions—which park his obese or diabetic or anxious or depressed patient should visit, on which days, and for how long—just as though he were prescribing medication.
In more recent years, a lot of research has focused on how urban nature helps people … focus.
A highly cited study by Marc Berman, John Jonides, and Stephen Kaplan gave some test participants a tough attention-related task that involved remembering numbers. Thus cognitively spent, some participants then took a walk through the famed Nichols Arboretum in Ann Arbor, Michigan, while others walked through the downtown area. When the participants returned to the lab and took the test again, the refreshed nature group scored significantly higher, the researchers reported in a 2008 issue of Psychological Science.
Other work is mixed on just how ensconced in leaves you need to be to get the cognitive boost. A study from 2012 found that the denser a park’s vegetation—meaning, less sight of the city through the trees—the better. But other work has found attention benefits from a mere 40-second micro-glimpse of a green roof, or even looking up from your screen to see a desk plant.
A walk through Nichols Arboretum in Ann Arbor, Michigan (above), gave a boost to attention compared with a walk downtown, according to a 2008 study. (Sean Munson / Flickr)
Even tots get a mental bump from grass and bark. In a 2009 study, kids aged 7 to 12 with diagnosed attention-deficit disorder showed better concentration after a 20-minute walk in the park, compared with children who walked downtown or in a neighborhood. “‘Doses of nature’ might serve as a safe, inexpensive, widely accessible new tool in the tool kit for managing ADHD symptoms,” the researchers concluded in a 2009 issue of the Journal of Attention Disorders. More recent work extended the cognitive benefits of urban nature to children without ADHD, too.
Kids 7-12 who walked in a park showed better concentration than those who took a stroll in a more urban environment. (Journal of Attention Disorders, 2009)
Aggression and restraint
The power of nature seems capable at times of transcending particular vulnerable environments. In a 2001 study, Illinois scholars Frances Kuo and William Sullivan found reduced levels of aggression in Chicago public housing residents whose view overlooked some trees, compared with others in the same complex who looked onto an empty common area. Kuo and Sullivan report in the journal Environment and Behavior that the additional mental fatigue that comes with not having visual access to nature might play a role in the diverging outcomes.
A study by Kuo and Sullivan as well as Andrea Faber Taylor, published the following year in the Journal of Environmental Psychology, extended that research to discipline among girls in the same housing complex. Young women with tree views performed better on tests of concentration, delayed gratification, and inhibited impulsivity compared to those with barren views. “Perhaps when housing managers and city officials decide to cut budgets for landscaping in inner city areas, they deprive children of more than just an attractive view,” the researchers concluded.
Other work has found reduced levels of road rage among test participants who watched videos of a drive along roads lined with and without nature. In a 2003 study, some participants watched the car cruise along a normal asphalt highway, others saw a little bit of greenery in a garden highway, and a third group saw dense vegetation in a scenic parkway. Afterward they all tried their hand at an anagram that, unbeknownst to them, was impossible (e.g. DATGI—eyes back on the road, please!); those who’d observed the scenic drive showed less impatience, working on the puzzle for 90 more seconds before giving up.
Participants who watched a drive along a scenic parkway showed more patience when tackling an unsolvable anagram than did those with other views. (Environment and Behavior, 2003)
If you’re in a hospital, the last thing you’re really worried about is the view. But having a window that looks onto trees has been shown to have a measurable difference in patient outcomes. In a classic study published in Science in 1984, Roger Ulrich found that gallbladder surgery patients whose hospital rooms overlooked nature had “shorter postoperative hospital stays, received fewer negative evaluative comments in nurses' notes, and took fewer potent analgesics” than those whose windows faced a brick wall.
And these days, if the medical trend noted by James Hamblin catches on, you just might be prescribed a walk in the park on your way out.
For whole article: http://www.citylab.com/weather/2015/10/the-pretty-much-totally-complete-health-case-for-urban-nature/411331/