City living is going strong. Approximately 3.5 billion people across the globe are city dwellers, and according to the director of the United Nation’s Human Settlement Program, that population will double by 2050. But city living can take a heavy toil on your mental health. Here’s what research has shown thus far:
- People who live in cities are at greater risk for anxiety, depression, and other mental disorders.
- City dwellers have lower levels of stress hormones immediately after spending time in nature—even if it’s just a walk through the park.
- Whether living in the city, the suburbs, or the country, being outside in nature has a positive impact on your emotional health.
But, is the emotional uplift of spending time in nature linked to actual physical changes in your brain? Stanford researchers believe so.
Beat Brooding with a Walk in the Park
Stanford researchers showed that volunteers who walked through a lush and green section of campus were more attentive and happier than volunteers who walked for the same amount of time next to a high-traffic area. However, the study didn’t assess any neurological mechanisms that may have been activated and contributing to the more positive mental states. Expanding on the research, the same team conducted a second study that zeroed in on the effect a walk through nature may have on a person’s tendency to brood.
What does it mean to brood? To obsessively go over and over in your mind all the things that are wrong with you or wrong with your life. Scientists label it “morbid rumination” and if left unchecked, brooding can develop into full-blown depression.
Thirty-eight healthy volunteers were asked to complete a questionnaire that evaluated their level of brooding. Researchers then tested for activity in the region of the brain known as the subgenual prefrontal cortex; high levels of activity in the subgenual prefrontal cortex have been linked to a greater tendency to brood.
Participants were split into two groups. Group 1 walked for 90 minutes through a quiet, nature-filled part of campus, and group 2 walked for the same amount of time next to a loud, multi-lane highway. Volunteers could not walk with each other or listen to music.
After the walk, researchers checked for activity in the subgenual prefrontal cortex using brain scans that tracked blood flow through the brain—increased blood flow indicates increased activity in that region. Volunteers also completed a second questionnaire to determine their level of brooding.
Results weren’t surprising: those who walked next to traffic showed no changes in broodiness and their blood flow was still high. Participants who walked through nature, however, enjoyed significant improvements in their mental state according to the questionnaire, and also exhibited decreased blood flow to the area of the brain associated with brooding. All in all, those exposed to nature had quieter brains.
Was it the beauty of nature that quieted their brains? Did they have more time to reflect in silence on solutions to their problems, and that’s what quieted their brains? Scientists don’t know, but what we do know is that the mystical, magical realm of nature is clearly good for your emotional health and mind. Without a doubt, city dwellers need nature!
