Evidence mounts that traffic slows cognitive development in children

Evidence from Spain backs up earlier assessments that suggest pupils struggle to learn, explore and problem-solve when educated close to busy roads. 

A new study of 38 schools in Barcelona has added to the mounting evidence that heavy traffic has a detrimental impact on the cognitive development of children. 

Previous research has pointed to clear correlations between high air pollution and problems with educational attainment. Now a fresh investigation conducted by the Barcelona Institute for Global Health and published in PLoS Magazine points to cars and other road vehicles as a catalyse for poor performance among pupils, albeit this time the focus is on traffic noise, not emissions. 

Part of the BREATHE project, the study took into account the experiences of 2,680 students aged between seven and 10 years, and the impact of noisy roads on two specific areas – attention, and working memory. Conducted over a 12-month period between 2012 and 2013, all participants took cognitive tests on four occasions during the project, which were aimed at assessing both memory and attention at the time, and also educational evolution. Meanwhile, noise measurements were taken in front of each school, inside classrooms and in playgrounds. 

The results show a considerable reduction in complex working memory and attention among students attending schools near noisy roads, with a 5DB increase lowering working memory by as much as 11% and attention by 4.8%. The impact is more pronounced inside classrooms, and – interestingly – does not carry through to noise exposure at home, which was gauged using a 2012 road traffic noise map of Barcelona. Those behind the work believe the difference may be due to ‘noise exposure at school [being] more detrimental as it affects vulnerable windows of concentration and learning processes.’ 

Previous studies have identified strong links between air pollution levels – which logically are higher in area where there is more traffic noise – and cognitive performance. It is not clear how these two factors were distinguished from one another in the Barcelona study. In 2019, Air Quality News published a feature by Amadeo D’Angiulli, professor of Developmental Cognitive and Social Neuroscience at Carleton University, on the relationship between air pollution and cognitive decline in children, alongside Alzheimer’s and death.

Image credit: Barcelona Institute for Global Health