There’s strong evidence that exposure to nature can improve patients’ recovery time(1), and that short “micro-breaks” spent looking at images of nature can improve attention levels and work performance(2), but now a recent paper from Gregory Bratman of Stanford University has attempted to document the effects that exposure to nature can have on our brains themselves.
The cognitive neuroscience study used brain scans and questionnaires to determine the effects that a walk through either a natural area near the Stanford campus, or down a busy road in California, had on the cognitive function of study participants.
The questionnaire was designed to measure the participants’ tendency towards negative thinking, which has been linked to depression(3). Brain scans were performed both before and after the walk, focusing on a region of the brain known as the subgenual prefrontal cortex – an area associated with thought patterns linked to depression.
Less Likely To Develop Depression
The study found that individuals who walked through nature were less prone to thought patterns associated with depression.
But what was of particular interest to researchers was the fact that brain scans showed decreased activity in the subgenual prefrontal cortex in the participants who spent time in nature(4).
“This provides robust results for us that nature experience, even of a short duration, can decrease this pattern of thinking that is associated with the onset, in some cases, of mental illnesses like depression,” said one of the study’s lead researchers(5).
Urbanization And Mental Illness
The implications of this study are significant – there is already a demonstrated link between urbanization and mental health problems like anxiety and depression(6).
With 50 percent of the human population of Earth living in urban areas, many billions of people are exposed to stressors that are less common in rural areas.
For example, waking up to the sound or a garbage truck outside your window may seem like a minor annoyance, but it can have a negative effect on your psyche – especially when combined with dozens of similar annoyances throughout the day.
The study authors speculate that natural environments like forests and parks allow for “positive distractions” from these daily stressors – actively helping to counteract negative thought patterns that can contribute to mental illness like depression and anxiety.
Brain Scan Controversy
While all of this may make sense to anyone who’s ever spent a prolonged period of time living in a city, there is some controversy about the validity of brain scans as a means of anticipating mental illness.
Certainly, illnesses like anxiety and depression can have many causes – there are not only environmental factors, but genetic and lifestyle factors at play as well(7).
But the study authors hope that the results of their research can help shed some light on how our environments can contribute to the development of these illnesses. Certainly, it couldn’t hurt most of us to make sure we experience nature every once in a while.
[mks_toggle title=”sources” state=”close “]- https://www.ncbi.nlm.nih.gov/pubmed/6143402
- https://www.ncbi.nlm.nih.gov/pubmed/24885178
- https://www.apa.org/monitor/nov05/cycle.aspx
- https://www.pnas.org/content/early/2015/06/23/1510459112
- https://www.eurekalert.org/jrnls/pnas/pdfs/pnas.201510459.pdf
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2996208/
- https://blogs.scientificamerican.com/guest-blog/controversial-science-of-brain-imaging/