Several studies have shown the link between urban living and the increased risk of mental disorders, such as anxiety disorders, depression and schizophrenia, so it is very important to understand how the impact of the urban and natural environment affects mental health and the brain.
The human brain has always been shaped by the environment; today more than half of the world ' s population lives in urban areas, and it is expected to increase to almost 70 per cent by 2050, but it has been shown that living in urban areas is a risk to mental health: anxiety, mood disorder, deep depression and schizophrenia are 56 per cent more common in urban than in rural areas.
In contrast, a growing number of studies have demonstrated the cognitive and emotional advantages of being in a natural environment, in particular that communication with nature has improved the volume of work memory, helped restore attention and reduced stress, and that evidence of these beneficial effects has been found both in psychological assessments and in physiological indicators.
Proved effect on the area of the brain involved in stress management
With bracelets that measure different physiological parameters, they had to follow a particular route, not straying from the course and not using their mobile phones on the way to avoid distraction. After a walk, each participant made another FMT and then performed an additional stress assignment. The results of the study showed that, after outdoor walks, the activity of the almonds declined and after a walk in the urban environment remained stable. Thus, nature has a positive effect on the stress-related parts of the brain.
Useful results for urban planning policies
This is the first study to prove the causal link between nature and mental health. "," says Simone Kyun, head of Lisa Maitner's environmental neuronauque team at the Max Planck Institute for Human Development.
If a short walk in nature is enough to have a positive impact on the parts of the brain involved in stress management, it can be an effective preventive measure against mental stress and possibly disease, and it can also mitigate the potentially harmful effects of urban life on the brain.
Simone Kyun and her colleagues have already shown in a study published in Scientific Reports in 2017 that urban residents who live within a kilometre of the forest have a physiologically healthier structure of the almonds and are likely to be more resistant to stress, and that a Japanese study has also shown that walking in the forest, as well as sitting and watching it, has reduced the concentration of hemoglobin in the prefrontal area, which has been interpreted as a sign of relaxation.
In order to study the beneficial effects of nature on different population groups and age groups, Kyung and her team are currently working on another study aimed at determining the impact of the natural and urban hour walk on the stress of mothers and their infants. Based on these results, this study confirms the importance of urban planning policies to create more accessible green areas in cities to improve the mental health and well-being of citizens.