2025 Theses Doctoral

Associations Among Early Adversity, Child Epigenetics, And Behavioral and Cognitive Development Across the First Few Years of Life

Sperber Knott, Jessica

Developmental psychobiologists theorize that epigenetic pathways play a crucial role in explaining the biological embedding of socioeconomic disadvantage and early life stress on health and well-being across the lifespan. Biological aging as indexed via epigenetics is a promising biomarker of both early life adversities and deleterious health outcomes across multiple domains, and recent advances suggest these associations are detectable within childhood itself. However, little is understood about when these associations emerge during development, under what conditions, and the meaning of such biomarkers for young children’s psychological development.

The present dissertation examined disparities in epigenetic aging using a diverse sample of mother-infant dyads followed from pregnancy through toddlerhood. Study 1 found that socioeconomic and stress-related perturbations in epigenetic aging are not robustly detectable at birth, but appear to emerge by 30-months postpartum. Study 2 found no differences in child epigenetic aging as a result of exogenous exposure to the social experience of the COVID-19 pandemic. Study 3 found that child epigenetic aging was not a reliable indicator of children’s concurrent cognitive or behavioral development.

Collectively, these findings suggest that adversity-related disparities in biological aging are detectable within the first few years of life; are not affected by the social experience of the pandemic; and are not informative for psychological development in real-time. Implications for the biological embedding of adversity, the application of epigenetic clocks to pediatric samples, and future research are discussed.