Answer: The population density of one's current geographic residence.
Explanation:
Daniel Kennedy and Ralph Adolphs, both from the California Institute of Technology, noted in an essay published in the same issue of Nature.
Kennedy and Adolphs noted that city populations might, to a certain extent, be a self-selecting population. "There are wide variations in individuals' preferences for, and ability to cope with, city life: some thrive in New York City; others would happily swap it for a desert island," they wrote in their essay. One key reason for this might be "the perceived degree of control that people have over their daily lives."
Kennedy and Adolphs Also suggested future work focusing on ways of "softening" the urban landscape via better architecture and urban planning.
Even though city dwellers showed differences in their brains, their levels of the stress hormone cortisol was on par with their rural peers.
Social threat, lack of control and subordination are all likely candidates for mediating the stressful effects of city life, and probably account for much of the individual differences."
Dr Daniel Kennedy and Prof Ralph Adolphs, both at the California Institute of Technology, said that there are wide variations in a people's preferences for, and ability to cope with, city life.
