Children Living Near Woodlands Have Better Cognitive Development, Study Says

The study, published in Nature Sustainability, looked at the links between different types of natural urban environments and the pupils' cognitive development, mental health and overall well-being.

The environments were divided into what planners call green space (woods, meadows and parks) and blue space (rivers, lakes and the sea), with green space separated further into grassland and woodland. Researchers used satellite data to help calculate each adolescent's daily exposure rate to each of these environments within 50m, 100m, 250m and 500m of their home and school.

After adjusting for other variables, the results showed that higher daily exposure to woodland (but not grassland) was associated with higher scores for cognitive development, and a 16% lower risk of emotional and behavioural problems two years later.

A similar but smaller effect was seen for green space, with higher scores for cognitive development, but this was not seen for blue space. The researchers note though that access to blue space in the cohort studied was generally low.

Examples of other explanatory variables considered included the young person's age, ethnic background, gender, parental occupation and type of school, e.g., state or independent. The level of air pollution might have influenced adolescents' cognitive development, but researchers did not feel these observations were reliable or conclusive, and these require further investigations.

It is already estimated that one in 10 of London's children and adolescents between the ages of five and 16 suffer from a clinical mental health illness and excess costs are estimated between £11,030 and £59,130 annually for each person. As with adults, there is also evidence that natural environments play an important role in children and adolescents' cognitive development and mental health into adulthood, but less is known about why this is.

The results of this study suggest that urban planning decisions to optimise ecosystem benefits linked to cognitive development and mental health should carefully consider the type of natural environment included. Natural environments further away from an adolescent's residence and school may play an important role too, not just their immediate environment.

To arrive at the findings, researchers analysed a longitudinal dataset of 3,568 adolescents between 2014 and 2018, whose residence was known, from the Study of Cognition, Adolescents and Mobile Phones (SCAMP) across the London metropolitan area. They assessed adolescents' mental health and overall well-being from a self-reported Strengths and Difficulties Questionnaire (SDQ) -- covering areas such as emotional problems, conduct, hyperactivity and peer problems -- and the KIDSCREEN-10 Questionnaire taken by each adolescent for SCAMP.

Limitations of the study include an assumption that living or going to school near natural environments means more exposure to them, which may not always be the case due to how easily they can be accessed by a child or young person or how usable they are.

Also, a considerable proportion of the participants (52.21%) were in the group whose parents had a managerial/professional occupation, so adolescents in less favourable socio-economic groups may be underrepresented and pupils requiring special needs may be differently affected compared with their peers. Crime rates, which may have influenced the results too, were not taken into account.

The study was supported by the Natural Environment Research Council, the Medical Research Council and the National Institute for Health Research, and involved researchers from UCL, Imperial College London and Birkbeck, University of London.