New European research suggests that living near nature can have a positive effect on the brains of city dwellers and especially on the amygdala, a part of the brain important for processing stress.

Carried out by the Max Planck Institute for Human Development in Germany, the study looked at the effect of being close to nature on the brains of city dwellers.

It is already known that this population is at a higher risk of psychiatric illnesses such as depression, anxiety disorders, and schizophrenia than country dwellers, with previous comparisons also showing that city dwellers have higher activity levels in the amygdala -- a part of the brain important in processing stress and reactions to danger.

Noise, pollution, and the high number of people in the small space of a city are also all contributing factors to chronic stress.

"Research on brain plasticity supports the assumption that the environment can shape brain structure and function," explained first author Simone Kühn, "Studies of people in the countryside have already shown that living close to nature is good for their mental health and well-being. We therefore decided to examine city dwellers."

For the study Kühn and her team looked at 341 adults aged 61 to 82. The participants were asked to complete memory and reasoning tests and undergo MRI scans to assess the structure of stress-processing brain regions, especially the amygdala.

The MRI data was then combined with geoinformation on the participants' places of residence in order to examine the influence of nature close to peoples' homes on these brain regions.

The team found that city dwellers who lived close to a forest were more likely to have a physiologically healthy amygdala structure, suggesting that they were better able to cope with stress.

This findings still held true even after the team took into account other influencing factors such as education and income levels.

However, they were unable to find an association between the brain regions examined in the study and urban green, water, or wasteland.

The team commented that at the moment it is not possible to determine whether living close to a forest has positive effects on the amygdala, or whether people with a healthier amygdala are more likely to choose to live in an urban area close to a forest.

However, based on their present knowledge they believe the first explanation is more probable.

With almost 70 per cent of the world population expected to be living in cities by 2050 the team also suggested that the results could therefore be important for urban planning, however they added that the findings would need to be confirmed with further studies and in other cities.

The findings can be found published online in the journal Scientific Reports.