Does exposure to nature make children more intelligent? : analysis in Polish children with and without ADHD

Previous studies have shown that exposure to nature and physical activity (PA) may be associated with higher intelligence in children. We examined whether there is an association between lifelong exposure to greenspace and bluespace and intelligence in children aged 10–13 with and without attention deficit hyperactivity disorder (ADHD), and whether PA mediates this association. The sample (N = 714) was collected within the NeuroSmog case-control study, where children with (N = 206) and without ADHD (N = 508) were recruited from 18 towns in Southern Poland. Nature exposure was estimated as the sum of the z-scores of the objective and perceived measures. Objective greenspace exposure was defined as the percentage of grass and tree cover in 500 m and 1 km buffers around lifelong residential addresses, respectively. Objective bluespace exposure was defined as the percentage of water cover in 500 m and 1 km buffers. Perceived greenspace/bluespace was measured as the parent-rated availability, quality, and use of greenspace/bluespace. Intelligence was assessed using the Polish version of the Stanford-Binet Intelligence Scales, 5th edition (SB5). SB5 Full Scale Intelligence Quotient (IQ), Nonverbal IQ, Verbal IQ, five factor and ten subtest scores were analysed as outcomes. The associations between nature and IQ scores were assessed by linear regressions separately for cases and controls, adjusting the models for sex, parental education, and urbanicity. Structural equation modeling was implemented to test whether PA mediated the association between nature and intelligence. None of the greenspace or bluespace measures were consistently associated with intelligence. PA was not found to be a mediator. We did not find evidence that higher lifelong nature exposure is associated with higher intelligence in Polish schoolchildren with or without ADHD. This casts doubts on whether exposure to nature has relevant influence on IQ

Air pollution and attention in Polish schoolchildren with and without ADHD

Background: Development and functioning of attention—a key component of human cognition—can be affected by en vironmental factors. We investigated whether long- and short-term exposure to particulate matter with aerodynamic diameter < 10 μm (PM10) and nitrogen dioxide (NO2) are related to attention in 10- to 13-year-old children living in Polish towns recruited in the NeuroSmog case-control study. Methods: We investigated associations between air pollution and attention separately in children with attention deficit hyperactivity disorder (ADHD, n = 187), a sensitive, at-risk population with impaired attention and in population based typically developing children (TD, n = 465). Alerting, orienting, and executive aspects of attention were mea sured using the attention network test (ANT), while inhibitory control was measured with the continuous performance test (CPT). We assessed long-term exposure to NO2 and PM10 using novel hybrid land use regression (LUR) models. Short-term exposures to NO2 and PM10 were assigned to each subject using measurements taken at the air pollution monitoring station nearest to their home address. We tested associations for each exposure-outcome pair using adjusted linear and negative binomial regressions. Results: We found that long-term exposures to both NO2 and PM10 were associated with worse visual attention in chil dren with ADHD. Short-term exposure to NO2 was associated with less efficient executive attention in TD children and more errors in children with ADHD. It was also associated with shorter CPT response times in TD children; however, this effect was accompanied by a trend towards more CPT commission errors, suggestive of more impulsive performance in these subjects. Finally, we found that short-term PM10 exposure was associated with fewer omission errors in CPT in TD children. Conclusions: Exposure to air pollution, especially short-term exposure to NO2, may have a negative impact on attention in children. In sensitive populations, this impact might be different than in the general population

Association of residential and school green- and bluespace with academic performance in 10-13-year-old Polish schoolchildren with and without attention deficit hyperactivity disorder

Background: Several studies, mostly based on the USA data, have reported that school greenspace was associated with better academic performance. However, nearly all of them were conducted on aggregated data. We are among the first individual data-based studies worldwide to examine whether exposure to school and residential green- and bluespace can boost academic performance. Methods: NeuroSmog is an ongoing case-control study investigating the impact of air pollution on brain development in children with and without attention deficit hyperactivity disorder (ADHD). 658 children aged 10 to 13 years from 18 large and small towns in southern Poland constituted the analytical sample. Information about latest end-of-year school grades in Polish and maths was collected by the parent report while perceived academic performance in these subjects was collected by the Youth Self-Report. Tree, grass, and water cover, as well as overall vegetation, were abstracted in Euclidean buffers of 500 and 1000 m around concurrent school and residential addresses. Perceived green- and bluespace data were also collected. Adjusted for age, sex, parent education, financial situation, and urbanicity, logistic models were fitted to assess the asso ciations between each exposure-outcome pair. Result: We found no consistent associations between academic performance and school or residential green- and bluespace. This held true for children with and without ADHD. Conclusions: Higher residential and school green- and bluespace do not seem to be sufficient for better academic performance

Neurosmog:Determining the impact of air pollution on the developing brain: Project protocol

Exposure to airborne particulate matter (PM) may affect neurodevelopmental outcomes in children. The mechanisms underlying these relationships are not currently known. We aim to assess whether PM affects the developing brains of schoolchildren in Poland, a country characterized by high levels of PM pollution. Children aged from 10 to 13 years (n = 800) are recruited to participate in this case–control study. Cases (children with attention deficit hyperactivity disorder (ADHD)) are being recruited by field psychologists. Population-based controls are being sampled from schools. The study area comprises 18 towns in southern Poland characterized by wide-ranging levels of PM. Comprehensive psychological assessments are conducted to assess cognitive and social functioning. Participants undergo structural, diffusion-weighted, task, and resting-state magnetic resonance imaging (MRI). PM concentrations are estimated using land use regression models, incorporating information from air monitoring networks, dispersion models, and characteristics of roads and other land cover types. The estimated concentrations will be assigned to the prenatal and postnatal residential and preschool/school addresses of the study participants. We will assess whether long-term exposure to PM affects brain function, structure, and connectivity in healthy children and in those diagnosed with ADHD. This study will provide novel, in-depth understanding of the neurodevelopmental effects of PM pollution