Children Who Live Near More Trees and Parks Scored Better on Attention Tests, a 12,000-Child Study Finds

The paper's title also reports an association with higher crystallised intelligence, the stock of knowledge and vocabulary that schooling builds, though the university's account concentrates on attention.

Why would trees help a child concentrate?

The researchers tested two plausible routes. Physical activity in nature did not explain the association. Air quality partly did: neighbourhoods with more canopy had cleaner air, and that accounted for some of the attention advantage. Fowler said there is something to the idea that air quality partially explains why green space helps attention, while stressing that the mechanism is not fully understood.

The classic account, attention restoration theory, holds that natural scenes let the effortful, directed kind of attention rest. The authors note that this restorative effect appears to need a sense of safety, and that it is weaker when the person in the park is scrolling a phone. Not just any strip of grass will do.

What the study does not show

This is an observational association, not a trial. Families who live near parks differ from those who do not in ways no model fully captures, and the authors themselves point out that some earlier studies found little effect of green space on attention. The analysis cannot say that planting trees would raise a given child's test scores, only that the two travel together in a very large sample after sensible adjustments.

What it does offer is a reason for city planners to treat canopy and parks as part of children's cognitive environment rather than an amenity. The ABCD cohort is still being followed into adolescence, which will let the same team ask whether the attention gap persists, grows or fades as the children age.