Talking a walk amongst plants is good for you in many ways, but why? This questions recently bothered some neuroscientists and they set out to answer it. It turns out that exposure to nature changes the way blood flows in our brain in a way that makes us feel better.
Then the scientists randomly assigned half of the volunteers to walk for 90 minutes through a leafy, quiet, parklike portion of the Stanford campus or next to a loud, hectic, multi-lane highway in Palo Alto. The volunteers were not allowed to have companions or listen to music. They were allowed to walk at their own pace.
Immediately after completing their walks, the volunteers returned to the lab and repeated both the questionnaire and the brain scan.
As might have been expected, walking along the highway had not soothed people’s minds. Blood flow to their subgenual prefrontal cortex was still high and their broodiness scores were unchanged.
But the volunteers who had strolled along the quiet, tree-lined paths showed slight but meaningful improvements in their mental health, according to their scores on the questionnaire. They were not dwelling on the negative aspects of their lives as much as they had been before the walk.