Nature and the Brain
A recent study has shown that a 60-minute walk in nature reduces activity in the amygdala, a region of the brain chiefly associated with stress and fear processing, when compared with an hour’s walk on a busy shopping street in Berlin. Similarly, spending time in nature has been shown to decrease rumination – defined by this study as the process of continuously or repetitively thinking negative thoughts and has been shown to improve performance on creativity problems. Even just viewing pictures of nature has been shown to improve memory and other cognitive functions, as well as reducing blood pressure, pulse rate and muscle tension, compared with viewing images of urban scenes. In a prison in Michigan, residents who had a view of the countryside from their cells were found to use the prison medical services less than those with an internal courtyard view. Plants, particularly trees, not only add oxygen to the air but remove toxic metals, nitrogen oxides and sulphur dioxide. They also reduce noise, heat, wind, water, erosion and dust.
Mycobacterium vaccae is a type of bacteria which lives inside soil, ingestion of which through inhalation or simply through contact with the skin causes serotonin production in the brain in a similar way to antidepressant drugs like prozac. Experiments with rats have shown that the effects of ingestion of this bacterium can last up to 3 weeks. Scientists have suggested that mycobacterium vaccae could be given to those likely to suffer stress, to act as a protective measure against mental health disorders such as post-traumatic stress disorder, anxiety and depression.
Serotonin is not only involved in mood regulation but also in the digestion of food. Most of your body's serotonin is in the hollow organs of the digestive system where its role is to help control bowel function and play a role in protecting the gut. Serotonin release speeds digestion to rid your body of unwanted foods or toxic products. Terroir is the word chefs and farmers use to describe the particular taste and other effects that soil gives wine and other natural products, and now science is beginning to unravel how this really works.
Another experiment showed participants images of natural scenes before testing them on economic games. Participants exposed to more beautiful scenes of nature were found to make decisions that were more generous and trusting in the games. In another part of this study, participants were asked to fill out a questionnaire whilst sitting in a room with plants. Half the participants were in a room with more beautiful plants and half were in a room with less beautiful plants. Afterwards, the participants were told that the experiment was over, but if they wanted to they could volunteer to make paper cranes for a relief effort program in Japan. Results showed that participants who were in the room with the more beautiful plants made more paper cranes. These results been explained by the feelings of awe and wonder that beautiful nature inspire, in turn making us feel less self-interested and giving us a desire to trust in and strive to improve the social and physical world in which we live.
Nature’s produce of course benefits the body, which we now know to be inextricably linked to the mind, these studies and others show the direct beneficial effects from nature towards society and individual. So, I’m off to plant a seed, hug a tree and breathe in deeply all nature has to offer.
Art by Igor Morski, thanks to original creator.