This study monitors the cognitive development of a very large number of schoolchildren in areas that are critical for learning, to investigate the possible influence of road traffic noise in the streets around schools.

Existing data so far pointed to an effect of noise pollution on cognitive skills, but this study makes significant progress with a longitudinal view that allows us to conclude that there is a direct relationship between the existence of a high level of traffic noise and slower cognitive development in children.

At the methodological level, both the size and representativeness of the sample and the care taken to explore the role of other variables that might influence the results are surprisingly positive. Thus, the results are solid and leave no room for doubt: noise pollution associated with traffic has a negative impact on the cognitive health of our children. This study invites to develop actions to reduce noise levels in cities, and to implement cognitive stimulation programmes for students in schools in areas with high noise pollution.