It has long been theorized that being born and brought up in a city may lead to an increased risk of ailments like depression, anxiety, schizophrenia and other mood disorders. This study analyzed the effects of living in a city on a person’s capability to handle stress by using three experiments involving brain scans. The results showed that a part of the brain called the amygdala, responsible for the processing of emotions, showed increased activity in urban dwellers. These people also had an increased incidence of stress and mood problems. This study paves the way for researchers to understand the effects of urbanization on the human psyche.
There is an upsurge in urbanization around the world, with 69 percent of the population estimated to be urban dwellers by 2050. Although living in the city has benefits like access to better healthcare, nutrition, sanitation and housing, it comes with increased heath risks. Multiple studies have shown that city dwellers are at a higher risk of depression, anxiety and mood disorders. Even the risk of schizophrenia is doubled in those who are born and brought up in cities. This study is a compilation of three different experiments that analyzed brain functioning in response to stress in urban and rural dwellers, in order to evaluate the differences in their capacity to deal with stress.
* For the first experiment, the researchers recruited 32 participants from rural and urban areas. They were all subjected to a stressful situation where they had to solve arithmetic problems within a set time limit, while listening to the criticisms of an examiner through headphones.
* For the second experiment, another 47 participants were selected to perform arithmetic and other mental tasks. This time, they were criticized by an examiner through a video.
* For the third experiment, 37 adults were tested for their working memory and other matching tasks.
* All the participants underwent brain scans during the experiment. The extent of stress experienced by each of the participants was judged by the rate of their heartbeats, blood pressure and the levels of cortisol, a stress hormone, in their saliva.
* It was found that urban dwellers were similar to rural dwellers in all aspects at the beginning of the experiment and both groups were stressed up to the same levels. The city dwellers showed more activity in the amygdala region of their brain, which is responsible for processing of emotions, when compared to rural dwellers.
* Those who grew up in a city since birth showed a lesser coordination between the amygdala and the cingulate cortex of the brain than those who were not born in the city. Such a lack of coordination is generally observed in people who suffer from psychiatric disorders.
* City dwellers were more sensitive to stressful conditions than rural dwellers.
The authors of this study admit that the study limits itself to one point in time and does not follow the participants to assess the effects of prolonged living in a city over a longer period. They also agree that these participants lived in Germany, a developed country, where the rural and urban differences are fewer when compared to developing nations. They also add that the study included a small number of participants, most of whom were college students. Further studies using a larger and a more general population are suggested.
This study shows that living in a city or being born and brought up in an urban setting may affect the way people handle stress. This study may aid researchers in understanding the risk factors in the urban environment that make a person prone to mental ailments and other disorders. The findings of this study suggest that different regions of the brain are sensitive to the effects of city living at different times in a lifespan. This could help in the development of public health policies that tackle the problems associated with accelerated urbanization in the developing and developed countries of the world.
For More Information:
City Living and Urban Upbringing Affect Neural Social Stress Processing in Humans
Publication Journal: Nature, June 2011
By Florian Lederbogen; Peter Kirsch; University of Heidelberg, Mannheim, Germany
*FYI Living Lab Reports Are Summaries of the Original Research.