A walk in the park may have psychological benefits for people suffering from depression, according to researchers in Canada and the U.S.
“Our study showed that participants with clinical depression demonstrated improved memory performance after a walk in nature, compared to a walk in a busy urban environment,” said Marc Berman, Ph.D., a postdoctoral fellow at Baycrest’s Rotman Research Institute in Toronto. Berman conducted the research with scientists at the University of Michigan and Stanford University.
The researcher was quick to caution that nature walks are not a replacement for accepted treatments for depression, such as psychotherapy and drug treatment, but rather “may act to supplement or enhance existing treatments for clinical depression.”
He added that more research is needed to understand how effective nature walks are in improving psychological functioning.
Berman’s research is part of a cognitive science field known as Attention Restoration Theory (ART). It proposes that people concentrate better after spending time in nature or looking at scenes of nature because the peaceful settings give the brain a chance to relax, which helps restore or refresh cognitive capacities.
In a research paper published in 2008 in Psychological Science, Berman showed that healthy adults received a mental boost after an hour-long walk in a park, improving their performance on memory and attention tests by 20 percent, compared to an hour-long stroll in a noisy urban environment.
In his latest study, Berman explored whether a nature walk would provide similar cognitive benefits, as well as improve mood, for people diagnosed with clinical depression. Given that people with depression are characterized by high levels of rumination and negative thinking, the researchers were skeptical that a solitary walk in the park would provide any benefit at all and might end up worsening memory and exacerbating depressed mood.
For the study, 20 individuals diagnosed with clinical depression were recruited from the University of Michigan and surrounding Ann Arbor area. The 12 females and eight males, with an average age of 26, participated in a two-part experiment that involved walking in a quiet nature setting and in a noisy urban setting.
Before the walks, participants completed baseline testing to determine their cognitive and mood status. Before beginning a walk, the participants were asked to think about an unresolved, painful autobiographical experience. They were then randomly assigned to go for an hour-long walk in the Ann Arbor Arboretum or downtown Ann Arbor. They followed a prescribed route and wore a GPS watch to ensure compliance.
After completing their walk, they completed a series of mental tests to measure their attention and short-term/working memory and were reassessed for mood. A week later the participants repeated the entire procedure, walking in the location that was not visited in the first session.
According to the researchers, participants exhibited a 16 percent increase in attention and working memory after the nature walk compared to the urban walk.
The researchers also noted that interacting with nature did not alleviate depressive mood to any noticeable degree over urban walks, as negative mood decreased and positive mood increased after both walks to a significant and equal extent. Berman said this suggests that separate brain mechanisms may underlie the cognitive and mood changes of interacting with nature.