Scientists find clues to why city living leads to mood disorders

Researchers have discovered that two areas of the brain are directly affected by city living, leading to a greater risk of anxiety and mood disorders.

It was already known that city living is associated with poorer mental health - but not how or why. The new study provides some clues.

"The risk for anxiety disorders is 21 percent higher for people from the city, who also have a 39 percent increase for mood disorders," says co-author Jens Pruessner, a researcher at McGill's Douglas Mental Health University Institute in Montreal, according to TG Daily.

In people from the largest cities, researchers found that the amygdala -- the piece of the brain that processes emotions -- lit up with activity when the researchers chastised them. (Here, a big city was defined as one with a population of 100,000 or larger.) They couldn't say exactly why criticism fueled stronger brain reactions, but they figured it could be because of previous exposure to stress caused by other humans, says WebMD.