Go red for dyslexia and green for ADHD! A study of more than 400 children diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) found a link between the children’s routine play settings and the severity of their symptoms. Those who regularly play in outdoor locations with lots of green (grass and trees, for example) have milder ADHD symptoms than those who play indoors or in built outdoor environments.
ADHD prevalence in children
ADHD is one of the most common neurodevelopmental disorders of childhood. It is usually first diagnosed in childhood and often lasts into adulthood. Children with ADHD may have trouble paying attention or controlling impulsive behaviors and be overly active.
About 6 million children in the United States (9.8 percent) between ages 2 to 17 are estimated to have ever been diagnosed with ADHD, according to a national survey of parents using data from 2016-2019. Boys (13%) are more likely to be diagnosed with ADHD than girls (6%).
According to this survey, 6 in 10 children with ADHD had at least one other mental, emotional, or behavioral disorder. For children 2–17 years of age with ADHD, 62% were taking ADHD medication.
Nature and ADHD-related symptoms
Previous studies involving various measures, treatments, populations, and research designs have produced evidence of enhanced attention after exposure to natural views and settings. “Nature” experienced in a wide variety of forms—including wilderness backpacking, gardening, viewing slides of nature, restoring prairie ecosystems, and simply having trees and grass outside one’s apartment building—has been linked to better attention and effective outcomes.
In addition, there is evidence to suggest that nature can be helpful in addressing the impulsivity/hyperactivity axis of ADHD. One study revealed evidence of superior performance on objective tests of impulse control. In this study, low-income urban children were randomly assigned to architecturally identical apartment buildings with relatively green views versus relatively barren views. These findings suggest that green space immediately outside the home can help them lead more effective, self-disciplined lives.
Green time and ADHD
These findings led Taylor and Kuo to examine whether children diagnosed with ADHD might also benefit from “green time.” In their study, published in the American Journal of Public Health, they analyzed data from a national Internet-based survey from parents of children formally diagnosed with ADHD. They found that activities conducted in greener outdoor settings did correlate with milder symptoms immediately afterward, compared to activities in other settings.
The study explores other data from the same survey to determine whether the effect also is true for green play settings that are routinely experienced — the park, playground or backyard that a child visits daily or several times a week.
“Before the current study, we were confident that acute exposures to nature — sort of one-time doses — have short-term impacts on ADHD symptoms,” Kuo said. “The question was: if you’re getting chronic exposure, but it’s the same old stuff because it’s in your backyard or it’s the playground at your school, does it help then?”
To address this question, the researchers examined parents’ descriptions of their child’s daily play setting and overall symptom severity. They also looked at the children’s age, gender, formal diagnosis (ADD or ADHD), and total household income.
Outcomes of the survey
The analyses revealed an association between routine play in green, outdoor settings and milder ADHD symptoms. On the whole, the green settings were related to milder overall symptoms than either the ‘built outdoors’ or ‘indoors’ settings.
The researchers also found that children who were high in hyperactivity (diagnosed with ADHD rather than ADD) tended to have milder symptoms if they regularly played in a green and open environment, such as a soccer field or expansive lawn, rather than in a green space with lots of trees or an indoor or built outdoor setting.
The researchers found no significant differences between boys and girls or income groups in terms of the relationship between the greenness of play settings and overall symptom severity.