‘City slickers’ at increased brain stress: Study

By Dr. Ananya Mandal, MDJun 23 2011

German and Canadian neuroscientists have shown that living in a city or even being raised in one is associated with differences in the way the brain handles stress. They write in Nature that this is the first time researchers have used functional magnetic resonance imaging (fMRI) to identify specific brain regions that are affected by urban life.

They looked at fMRI scans of participants while stressing them by administering a timed math test (and then criticizing their performance), the researchers found that people who were current city dwellers had increased activity in the amygdala during stress, compared with those raised in small towns or rural areas.  Subjects who had been brought up in cities had greater activity in the perigenual anterior cingulate cortex. Both brain regions are involved in processing stress.

The fact that 70% of the world's population is projected to live in cities by the year 2050, wrote Caltech neuroscientists Daniel P. Kennedy and Ralph Adolphs in an accompanying article, “highlights the importance of understanding the effects that [urban] living conditions will have on human mental health.”

Although the work doesn't prove that living in the city causes the changes in the brain, it could one day help improve life for city dwellers, Jens Preussner, co-author and researcher at Montreal's Douglas Mental Health University, said in a statement. People who live in cities are at higher risk for anxiety, mood disorders and schizophrenia, Preussner explained. The brain pathways identified in the team's experiment may have something to do with this.  Understanding the basic biological mechanisms could lead to strategies to combat mental health problems among city dwellers in the future.

The authors suggest further research to identify exactly how various aspects of city living might change the way brains operate under stress. They also called on researchers to look at the positive side of city life, noting that studies have shown higher rates of suicide in rural areas than in cities.