Does air pollution change brain connectivity in children?
Following previous research showing atmospheric toxins alter the structure of the brain, a new study points to a change in brain connectivity among children exposed to dangerous levels of air pollution.
Using a data set involving 2,197 children born between April 2002 and January 2006 living in Rotterdam, the Netherlands, scientists have concluded that higher exposure to air pollution is associated with higher functioning brain connectivity in several regions at preadolescent age. In comparison, traffic noise is not.
Researchers used magnetic resonance imaging (MRI) to look at the impact of low air quality and noise on the brain, and specifically if this could be associated with alterations in the way different parts of the brain interact with each other. It was found that higher exposure to nitrogen dioxide and PM2.5 particulate matter from birth to three years of age, and nitrogen oxides between three and six years of age, led to higher brain connectivity.
This predominantly impacted on two networks, which have opposing functions – task negative, or default-mode which is activated when people are in a resting condition, and task positive, which activates when we are performing tasks that require concentration.
‘We still have to understand the consequences of this increased activity of both networks in resting conditions, but for now we can say that the brain connectivity in children exposed to higher levels of air pollution is different from what we would expect,’ said Laura Pérez-Crespo, first author of the study.
The period between birth and three years was found to be most susceptible to air pollution, with black carbon the pollutant most associated with brain connectivity changes. This comes after previous studies have shown air pollution exposure in early childhood alters the brain structure. Although traffic noise has not been linked, research from Spain published earlier this month pointed to slower cognitive development among children attending schools close to loud roads.
Image credit: Mike Cox