The amygdala is a part of the brain that processes emotions and reactions to dangerous situations.
A study shows that living in the city increases amygdala activity, contributing to overall stress.
Walking in nature reduces amygdala activity and decreases stress levels, benefiting mental health.
“Amygdala”: such a beautiful name. It comes from ancient Greek and means almond. The amygdala we are talking about today, however, is a fundamental part of our brain: oversimplifying a lot, it is, among other things, the emotion processing center. We are not speaking here only-or not only-of what we commonly refer to as emotions (fear, anger, sadness, etc.) but of something even more instinctive: the amygdala is in fact responsible for our often unconscious reaction to situations it considers dangerous. In any case and before anything potentially dangerous happens, the amygdala warns us.
This peculiar function probably saved a great many of our ancestors from ferocious beasts by putting them on the run, but it is a bit too sensitive for modern times, which are less dangerous, at least from the point of view of our exposure to these kinds of deadly risks. It is always on guard, however, and happens to be particularly so in cities, resulting in an increase in the general stress level, with consequences of various kinds: on the cardiovascular system, mood, and on our vision of life.
What if the problem is city life?
Starting with two studies from 2011 and 2012, German scholars tried to show what the role of the amygdala is and especially whether it is influenced by the context in which we live. The 2011 study demonstrated increased amygdala activity in those who lived in cities, while the 2012 study focused on the incidence in urban centers of those with schizophrenia.
The German scholars’ attempt was to show whether the higher statistical incidence of mental illness cases in urban centers was due to the difficulty of access to natural environments. In other words, the study wanted to show that the urban environment and living separate from the natural environment have an influence on the quality of people’s mental health.
To prove the point, the scholars identified 63 candidates-29 women and 34 men-with an average age of 27 and subjected them to functional MRI (a special MRI that detects which areas of the brain are activated during the performance of particular functions such as reading, speaking, walking, etc.) before and after the test. 31 of the participants walked for an hour on the streets of Berlin, 32 in the nature.
The unequivocal result on the two homogeneous groups (both composed of individuals of both sexes and similar in other characteristics) showed a decrease in activity in the regions of the brain that control stress levels, namely the amygdala in the “natural” group. In contrast, the “urban” group did not show an increase in the same activity, highlighting that, at the very least, walking in an urban setting helps keep stress within guarded levels. The most remarkable result, however, is that nature has an obvious and positive influence in lowering stress levels.
The importance of this research
You might think you already knew that and that you too have benefits from being out in nature, and you wouldn’t be wrong. The purpose of the research, however, is to give a scientific basis to certain insights, trying to understand what mechanisms underlie them and whether, for example, even a shorter exposure to the natural environment has benefits or whether at least an hour is needed.
The topic is then increasingly central because the data clearly show that the trend is to live clustered in urban centers. In short, cities are destined to grow more and more and, with them, so is the concentration of mental distress. Finding a way to alleviate or cancel them is an important contribution that science can make, starting with considerations that may superficially appear obvious.