Traffic Pollution Alters Brain Connectivity in School Children

In a recently published in NeuroImage researchers found that exposure to urban air pollution directly interferes with the functional maturation of the brain. The aim of the study, led by Jesús Pujol, a researcher at the Hospital del Mar, and coordinated by Jordi Sunyer, codirector and researcher at CREAL, an ISGlobal allied center, was to evaluate the extent of such potential effects of urban pollution on child brain maturation.

The researchers used general indicators of vehicle exhaust measured in the school environment and a comprehensive imaging evaluation. A subgroup of children participating in the BREATHE study underwent MRI to quantify regional brain volumes, tissue composition, myelination, cortical thickness, neural tract architecture, membrane metabolites, functional connectivity in major neural networks and activation/deactivation dynamics during a sensory task.

The researchers found that exposure to air pollution is associated with changes in the functional nature of the brain, with no apparent effect on the brain anatomy and structure or membrane metabolites. "In particular, we have seen that a higher concentration of pollutants is associated with less functional maturation of key brain networks to the integration of intellectual activity," Pujol said. This study found that the effect of pollution on the brain is the opposite effect of age. "During the school age, major brain systems integrate with each other and the bases of what will be the adult brain are established. In the study we found that urban pollution may slow the brain maturation process," Sunyer said.

“To test whether measured pollution was associated with cognitive performance, we used children's performance in working memory, motor response speed and attention. Higher pollution predicted slower reaction time in the participants with complete MRI and behavioral testing”, concluded Sunyer.

Reference

Pujol J, Martinez-Vilavella G, Macia D, Fenoll R,Alvarez-Pedrerol M,Rivas I,Forns J, Blanco-Hinojo L, Capellades J, Querol X, Deus J, Sunyer J. Traffic pollution exposure is associated with altered brain connectivity in school children . NeuroImage 2016;129:175-184.