Research Summary

Residential exposure to green space and early childhood neurodevelopment

Residential exposure to green space is positively associated with the neurodevelopment of young children

Environment International
2019

Research provides evidence of a positive association between exposure to high levels of residential surrounding green spaces and better cognitive development in primary school children. To determine if surrounding greenness might have a similar impact on younger children, this research examined the association of residential surrounding greenness with early childhood neurodevelopment.

Over 1000 mother-child pairs participated in this research. The mothers were recruited while still pregnant, and their children were followed until the age of two. Estimates of residential exposure to green space were based on the average normalized difference vegetation index (NDVI) within a 300-meter buffer area surrounding residential address at birth. The NDVI reflects satellite-based measures of surrounding greenness. Scores from the Bayley Scales of Infant Development administered to each child at about 24 months were used as a measure of their neurodevelopment. The BSID yields a mental development index (MDI) and a psychomotor development index (PDI).

An analysis of the data showed that exposure to higher levels of residential surrounding green spaces was associated with increased PDI and MDI scores. This association was strongest for children of mothers with lower pre-pregnancy body mass indexes. Reduced levels of traffic-related air pollution partially explained the association between exposure to residential surrounding green space and psychomotor development. The reduced air-pollution effect, however, did not apply to children’s mental development. Additionally, the lowest levels of traffic-related air pollution and the highest levels of physical activity were in areas with the highest amounts of surrounding greenness. The positive association between higher levels of residential surrounding green spaces and better cognitive development in young children found in this study are consistent with other studies conducted with adults and older children.

This research adds support to the body of evidence showing a positive association between exposure to residential surrounding green space and improved mental development in children. This study also adds to the literature by showing that this positive association applies to young children in the first two years of life and includes psychomotor development as well as mental development.