Residential greenspace exposure improves cognitive function.

Spending time in nature is associated with a variety of beneficial effects on mental and physical health. For example, recent research demonstrated that spending time in the natural environment reduces ruminative thinking. Other research indicates that walking in forested areas improves immune function, likely due to beneficial bioactive compounds produced by trees and inhaled by walkers. Findings from a new study suggest that residential greenspace exposure improves cognitive function in middle-aged women.

The investigation included more than 13,000 women enrolled in the Nurses' Health Study II, an ongoing study of health outcomes of female nurses living in the United States. The participants completed an online battery of cognitive tests that gauged psychomotor speed, attention, learning, and working memory. The investigators calculated the participants' exposure to greenspace based on satellite imagery of their residential address and evaluated the effects of possible mediators of cognitive function, such as air pollution exposure, depression, and physical activity.

They found that even after considering the participants' ages at assessment, race, and socioeconomic status, women who had greater greenspace exposure scored higher on aspects of psychomotor speed and attention than women with less exposure. The difference in scores was roughly equivalent to one year of chronological aging. Greenspace exposure did not appear to affect learning or working memory. They also found that exposure to pollution was not a mitigating factor, but depression was, aligning with previous research.

These findings suggest that residential greenspace exposure benefits cognitive performance in middle-aged women. They also underscore the importance of public health efforts to promote the incorporation of natural areas into urban planning.

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