With the onset of winter and the reduction of natural light, holidays, and ugh…the elections, we may have a tendency to fall into rumination. As a biologist rumination sounds like ruminants, which are mammals like deer that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion through microbial actions. It can be fun and rewarding to ruminate on a thought, pondering, digging deep into the realm of pure focus. Rumination, however, is a medical term describing the focused attention on the symptoms of one’s distress, and on its possible causes and consequences, as opposed to its solutions. Rumination is the retracing of past mistakes.
Rumination shows up as increased activity in a brain region called the sub-genual prefrontal cortex, a narrow band in the lower part of the brain that regulates negative emotions. If rumination continues for too long unabated, depression can set it.
While visits to psychologists to cure one’s ruination might be expensive, one of the most effective cures is free. An American nature philosopher penned the answer to rumination more than 150 years ago. In 1862, Henry David Thoreau wrote “When we walk, we naturally go to the fields and woods.” Thoreau extolled (and extolled and extolled) the virtues of walking in untamed environments. In the decades since, psychologists have proved him right. Exposure to nature has been shown repeatedly to reduce stress and boost well being.
The same research promoting walking in nature also shows that mere walking, especially in an urban/suburban environment does not yield the same effects. For a study published in the Proceedings of the National Academy of Sciences, Stanford scientists examined whether a nature walk could reduce rumination in 38 mentally healthy people. They picked city dwellers because, the researchers predicted, they would have “a somewhat elevated level of rumination resulting from the ongoing and chronic stressors associated with the urban experience.” Half the participants walked for 90 minutes through a grassland dotted with oak trees and shrubs (“views included scenic hills, and distant views of the San Francisco Bay”). The other half took a jaunt along El Camino Real, a four-lane, traffic-logged street in Palo Alto.
The nature walkers showed decreases in rumination and in activity in their sub-genual prefrontal cortices. The urban walkers showed no such improvements.
Decreases in rumination are linked to so-called “positive distractions,” like taking part in a hobby or enjoying a long chat with a friend. You’d think that walking in uninterrupted nature wouldn’t provide many diversions from a whorl of dark thoughts. Surprisingly, the opposite seemed to be true: Natural environments are more restorative, the authors write, and thus confer greater psychological benefits.
On this Sunday, brimming with color autumn day, it is time for a walk.~