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Published on: May 15, 2019
Prenatal exposure to air pollution and infant cognitive development using an eye-tracking visual paired-comparison
Carmen Peuters1, Joan Birulés2, Toni Galmés3
1ISGlobal, Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain.
Insights
Prenatal exposure to air pollution, including nitrogen dioxide and particulate matter, is linked to poorer infant cognitive development. Eye-tracking reveals this impact on recognition memory, highlighting pregnancy as a critical window for brain development.
Area of Science:
- Environmental Health
- Neuroscience
- Developmental Psychology
Background:
- Prenatal life is crucial for brain development.
- Limited research exists on prenatal air pollution's impact on infant cognition, with most studies using subjective assessments.
- Objective measures are needed to understand early neurodevelopmental effects of environmental exposures.
Purpose of the Study:
- To investigate the association between prenatal exposure to specific air pollutants and objective measures of infant cognitive development.
- To utilize eye-tracking technology for assessing infant recognition memory as an indicator of cognitive function.
- To identify critical windows of vulnerability during pregnancy for air pollution's neurodevelopmental effects.
Main Methods:
- Longitudinal study of 168 mother-child pairs from the Barcelona Life Study Cohort (BiSC).
- Assessment of prenatal exposure to nitrogen dioxide (NO2), black carbon (BC), PM2.5, and PM2.5-bound copper (Cu) and iron (Fe) using land-use regression (LUR) models.
- Cognitive performance measured at 6 and 18 months using an eye-tracking Visual Paired-Comparison (VPC) task assessing novelty preference for faces.
Main Results:
- Increased prenatal exposure to NO2, BC, PM2.5, Cu, and Fe was associated with decreased novelty preference in infants.
- A decrease in novelty preference was observed for each interquartile range increase in pollutants.
- Potential for stronger associations in male infants was suggested.
Conclusions:
- Prenatal exposure to common air pollutants negatively impacts infant cognitive development, specifically recognition memory.
- The prenatal period represents a sensitive window for air pollution's adverse effects on the developing brain.
- Eye-tracking offers a valuable, objective, and non-invasive method for early detection of neurodevelopmental impacts from environmental exposures.
Abstract:
Although the prenatal life is a critical period for brain development, very few studies have focused on prenatal exposure to air pollution in relation to infant cognition, and most studies have relied on carer-reported outcome assessment. We examined the association between prenatal exposure to air pollution and objective measurement of infant cognitive development using an eye-tracking methodology. The study was based on data from a subset of 168 mother-child pairs participating in the Barcelona Life Study Cohort (BiSC), Spain (2018-2023). Total exposure to nitrogen dioxide (NO2), black carbon (BC), particulate matter (PM2.5), and PM2.5 copper (Cu) and iron (Fe) content during pregnancy were assessed through integrating estimates of land-use regression (LUR) models with data on time spent at home, workplace, and during commuting. Cognitive performance was assessed longitudinally at 6 months (n = 156) and 18 months (n = 62) of age through an eye-tracking Visual Paired-Comparison (VPC) task that measured short-term recognition memory for faces. Linear mixed models were applied to explore the association between prenatal air pollution exposure and the percentage looking time at novel compared to familiar stimuli on the VPC task, adjusting for potential confounders. Results showed worse cognitive performance with increasing air pollution exposure: For each interquartile range increase of NO2, BC, PM2.5, Cu and Fe, novelty preference decreased with -2.0 (95 % CI: 4.7, 0.6), -2.5 (-4.6, -0.5), -3.9 (-7.0, -0.9), -2.1 (-4.0, -0.3), and -1.4 (-3.2, 0.3), respectively. There were suggestions for potentially stronger associations in boys. The findings highlight the pregnancy period as a window of vulnerability for the impact of air pollution on the developing brain, and values eye-tracking as an objective non-invasive tool for early detection of such impact.
