Researchers have revealed the beneficial effects of a walk in the forest on the human brain

Our ancestors lived in nature for millions of years. Cities, which are a whole new type of habitat, have many advantages. However, researchers have identified a relationship between this urban environment and the appearance of certain mental disorders such as depression, or even psychotic disorders such as schizophrenia.

According to the study published in Molecular Psychiatry, rub shoulders with wild nature, even for a short time, packed with mental health benefits. Spending time in nature lowers blood pressure, reduces anxiety and depression, improves mood, concentration, sleep and memory. This also allows a faster healing.

Although several studies have supported this link, there is still much to learn. Would taking a walk in a forest really provide all these benefits to the brain? And if yes, how ?

Functional magnetic resonance imaging

To better understand nature’s effect on the brain, researchers looked at the amygdala. It is a cerebral structure involved in the processing of stress, emotional learning and the deciphering of dangerous stimuli for the body. The study revealed that rural dwellers had less amygdala activated under stress compared to city dwellers. However, it is not certain that it is thanks to rural life.

Researchers from the Max Planck Institute have carried out a new study to understand this phenomenon. They have this time used the technique of functional magnetic resonance imaging (fMRI). 63 healthy adults participated in the experiment. They knew the study involved an MRI and a walk, but unaware of the purpose of the research.

Participants completed questionnaires before performing a working memory task. Then they passed fMRI scans, answering sometimes stressful questions. They were randomly assigned for a walk either in an urban environment or in a natural environment. They then underwent another CT scan, performing a additional stressful task. Finally, they completed another questionnaire.

The amygdala of the subjects who took an urban walk remained stable

fMRI scans showed a reduced amygdala activity after a walk in the woods. This proves that nature can cause beneficial effects in brain regions involved in stress, even in just one hour. In addition, the volunteers who walked in the forest were more attentive and enjoyed the walk more. This is consistent with fMRI findings, as well as previous research.

The researchers also learned that the amygdala activity of participants who took an urban walk did not neither decreased nor increased. This does not mean that the urban environment does not cause stress. However, the stressful effect of cities may not be as powerful as other studies suggest. Or maybe some stressor was missing on this ride.

SOURCE: SCIENCEALERT