2026 Theses Doctoral

Associations between Prenatal Exposure to Secondhand Smoke and Infant Attention: Mechanistic Insights into Decision Making

Shavel, Katherine E.

Secondhand smoke is among the most common toxic aerosols to which Americans are routinely exposed. Research has linked the chemical compounds of secondhand smoke to significant disruptions in cognitive function in both children and adults. Alarmingly, the neurotoxicants which comprise secondhand smoke can also cross the placenta and impact developing embryos. However, the underlying mechanisms by which prenatal exposure to secondhand smoke impact cognitive function are not yet fully understood. The goal of this dissertation was to contribute to such efforts by investigating the impact of prenatal secondhand smoke exposure on infant attention.

Data were collected from 83 mother-infant dyads enrolled in a longitudinal birth cohort study. Prenatal exposure status was obtained via maternal report, and infant attention was evaluated via the Multisensory Assessment of Attention Protocol. Demographic data on annual household income, ethnicity, infant age at assessment, maternal education, race, and sex were also evaluated as potential covariates. Effects of exposure on reaction time and accuracy on the Multisensory Assessment of Attention Protocol were assessed independently with frequentist statistics and simultaneously with Drift Diffusion Modeling.

Results indicated that prenatal exposure to secondhand smoke negatively impacts the neurodevelopment of attentional and decision-making capacities, manifesting in an impulsive response style and a difficulty balancing the speed-accuracy tradeoff, which can be detected as early as infancy. Clinical implications of these findings and future directions for research are discussed.