Nature takes stresses out of the brain

Tam-Tri Le, Phenikaa University (Hanoi, Vietnam)

September 6, 2022

Being close to nature is commonly considered beneficial for one’s well-being. Evidence from scientific observation, as well as anecdotal self-assessment, points to the “feel-good” effect of exposure to nature. A walk in the wood is said to relax one’s mind, but how? Recent research in neuroscience helps shed light on this relationship.

Living in urban areas can be stressful with all the noise, pollution, and competition. The amygdala plays an important role in stress processing and managing responses to emotional threats in the human brain. Those living in cities have increased amygdala activity compared to those living in rural areas, as a 2011 study published in Nature points out [1].


Forest trail, by ForestWander (CC BY-SA 3.0); https://commons.wikimedia.org/wiki/File:Forest-trail-trees_-_West_Virginia_-_ForestWander.jpg

A 2017 study published in Scientific Reports shows that urban residents living close to a forest have physiologically healthier amygdala structures, which can help them cope better with stress [2]. This study suggests a close connection between the brain structure and function – the amygdala in particular – and the stress relief effect of exposure to nature. In a 2022 study published in Molecular Psychiatry, researchers investigate deeper into the biological mechanism of this effect [3]. Using functional magnetic resonance imaging (fMRI), they found that amygdala activation decreases after a one-hour walk in the forest but remains stable after a walk in a busy street. This study provides causal evidence that even a short period of being in nature can reduce stress due to changes in brain activity.

As the human brain evolved from and has always been part of the natural world, there should be no surprise that it has built-in mechanisms to regulate itself from interactions with nature. It is how a biological information processing system is optimized through evolution [4]. Again, we are reminded that nature has much more value than what is believed to be monetarily exchangeable [5].

References

[1] Lederbogen F, et al. (2011). City living and urban upbringing affect neural social stress processing in humans. Nature, 474, 498–501. https://doi.org/10.1038/nature10190

[2] Kühn S, et al. (2017). In search of features that constitute an “enriched environment” in humans: Associations between geographical properties and brain structure. Scientific Reports, 7, 11920. https://doi.org/10.1038/s41598-017-12046-7

[3] Sudimac S, Sale V, Kühn S. (2022). How nature nurtures: Amygdala activity decreases as the result of a one-hour walk in nature. Molecular Psychiatry. https://doi.org/10.1038/s41380-022-01720-6

[4] Vuong QH. (2022). Mindsponge Theory. https://books.google.com/books?id=OSiGEAAAQBAJ

[5] Vuong QH. (2021). The semiconducting principle of monetary and environmental values exchange. Economics and Business Letters, 10(3), 284–290. https://doi.org/10.17811/ebl.10.3.2021.284-290