We've long accepted that taking a walk can clear one's mind, but not just any walk can do the trick, according to a new study. The right kind of walk, the same study shows, clears the mind and then some, meaning parents have even more reason to limit screen time and send kids to the park.
A majority of Americans live in cities and, as a whole, we spend far less time in nature. Research has shown that city dwellers are more prone to depression and are at a higher risk for anxiety and other mental illnesses. Even more acute is the risk for mental problems faced by city dwellers who have little or no access to green space.
Stanford graduate student Gregory Bratman had already conducted a simple study that found a short walk in Stanford's green space left subjects happier and more attentive and happier than the ones assigned to walk near traffic.
What Bratman wanted to further understand were the neurological mechanisms at work when humans spend even just a short amount of time among the trees and birds. So he and his research partners focused on whether nature affected their subjects' brooding.
Short answer: it does.
Brooding, or what scientists call morbid rumination, is our tendency to go over negative thought about our lives again and again on an endless loop. Brooding isn't healthy processing, it's actually a precursor to depression, the New York Time's Gretchen Reynolds explains.
Bratman had 38 subjects fill out a questionnaire to determine their level of brooding. They then scanned their brains to get a physiological baseline, particularly for activity in the subgenual prefrontal cortex, which lights up when brooding occurs.
They then sent the subjects out on 90-minute walks—alone and with no music.
The subjects who walked near the traffic did not have changed broodiness scores. Those who went out into nature, however, showed less activity in the subgenus prefrontal cortex and scored lower on the follow-up broodiness questionnaire.
Trees, peace, green space appear to be nature's Prozac. Or something like that.