Decades of research have shown that early psychosocial stress, including chronic adversity, can influence how a child's brain develops. However, families often face multiple overlapping challenges such as financial strain and caregiving stress, making it difficult to determine which factors are most important for early brain development.
A new study led by Boston Children's Hospital and published in the Proceedings of the National Academy of Sciences uses a network-based approach to analyze how different family conditions interact and affect infant brain development. The research team followed families during routine well-child visits at 4, 9, and 12 months at a primary care clinic serving mainly low-income communities. Parents filled out surveys about household income, perceived income sufficiency, and caregiver stress. At the same time, researchers measured infants' brain activity using electroencephalography (EEG).
The study found that caregivers who reported their income was never sufficient were also more likely to experience higher financial stress, lower educational attainment, and greater exposure to adverse life events. Among all these interconnected stressors, caregiver-reported income sufficiency was most strongly linked to children's brain development.
Infants in households where caregivers felt their income was never adequate showed signs of delayed brain maturation during their first year. These differences were especially clear in EEG measures related to alpha and beta brain activity—indicators associated with early brain development and later cognitive function.
"Children grow up in complex, dynamic environments where stressors are interconnected," said Haerin Chung, PhD, postdoctoral fellow at Boston Children's Hospital and co-first author of the study. "By using a network approach, we can identify which factors are most central—much like identifying influential nodes in a social network. Changing those central factors may have ripple effects across a child's developmental environment."
The findings raise questions about how meeting basic needs is biologically embedded during infancy. While the study did not pinpoint specific pathways involved, researchers suggest that several mechanisms could play a role. Factors such as nutrition and housing stability may influence brain development directly or indirectly through caregivers' ability to provide supportive interactions.
"Early brain development is shaped not only by biology, but by the everyday experiences infants have with their caregivers and their environment," said Carol Wilkinson, MD, PhD, attending physician and neuroscientist at Boston Children's Hospital and co-first author of the study. "Understanding which pathways matter most is an important next step for future research. Policies that strengthen supports affecting day-to-day financial stability during infancy may have lasting developmental benefits."
Overall, the results indicate that policies aimed at helping families meet basic needs during infancy could have long-term positive effects on child development.
