Effects of residential greenness on attention in a longitudinal study at 8 and 11-13 years

In an urbanizing world, with 55% of the population living in cities, it is essential to design friendly and healthy ones. An emerging body of evidence has associated greenspace exposure with improved cognitive development, including attentional function; however, the longitudinal studies looking at the association with attentional function are still scarce. Therefore, the objective of this study was to analyze the association of the exposure to greenspace and attention in school children. This study was based on 751 participants at 8 years and 598 at 11-13 years of two sub-cohorts of the INMA cohort study in Gipuzkoa and Asturias, Spain. Greenspace exposure at home was characterized using four indicators: (i) average of Normalized Difference Vegetation Index (NDVI) and (ii) Vegetation Continuous Field (VCF) in buffers of 100 m, 300 m, and 500 m around the residential address, (ii) availability of a green space within 300 m from the residential address, and (iv) residential distance to green spaces. Participants' attention was characterized twice at ages of 8 and 11 years, using the computerized Attentional Network Test (ANT). General linear models were used for the cross-sectional analyses and linear mixed effects model for the longitudinal analyses. Our cross-sectional analyses showed a statistical significant protective association between average NDVI at 300 m and inattentiveness (-7.20, CI 95%: 13.74; -0.67). In our longitudinal analyses, although we generally observed beneficial associations between greenspace exposure and attention, none attained statistical significance. No statistically significant indirect effect were seen for NO₂. Our findings add to the emerging body of evidence on the role of green spaces in neurodevelopment, which can provide the evidence base for implementing intervention aimed at promoting neurodevelopment in urban children.