Changes in Cognitive Outcomes in Early Childhood: The Role of Family Income and Volatility

Leveraging the science of early life predictability to inform policies promoting child health

Addressing the tremendous burden of early-life adversity requires constructive dialogues between scientists and policy makers to improve population health. Whereas dialogues focused on several aspects of early-life adversity have been initiated, discussion of an underrecognized form of adversity that has been observed across multiple contexts and cultures is only now emerging. Here we provide evidence for "why unpredictability?", including: 1. Evidence that exposures to unpredictability affect child neurodevelopment, with influences that persist into adulthood. 2. The existence of a translational non-human animal model of exposure to early life unpredictability that can be capitalized upon to causally probe neurobiological mechanisms. 3. Evidence that patterns of signals in the early environment promote brain maturation across species. 4. The uneven distribution of unpredictability across demographic populations that illuminates a possible focal point for enhancing health equity. We then outline the potential of unpredictability in terms of the "what"; that is, how might the concept of unpredictability be leveraged to inform policy? We emphasize the importance of interdisciplinary and community partnerships to the success of this work and describe our community-engaged research project. Finally, we highlight opportunities for the science of unpredictability to inform policies in areas such as screening, immigration, criminal justice, education, childcare, child welfare, employment, healthcare and housing.

Annual Research Review: The power of predictability - patterns of signals in early life shape neurodevelopment and mental health trajectories

The global burden of early life adversity (ELA) is profound. The World Health Organization has estimated that ELA accounts for almost 30% of all psychiatric cases. Yet, our ability to identify which individuals exposed to ELA will develop mental illness remains poor and there is a critical need to identify underlying pathways and mechanisms. This review proposes unpredictability as an understudied aspect of ELA that is tractable and presents a conceptual model that includes biologically plausible mechanistic pathways by which unpredictability impacts the developing brain. The model is supported by a synthesis of published and new data illustrating the significant impacts of patterns of signals on child development. We begin with an overview of the existing unpredictability literature, which has focused primarily on longer patterns of unpredictability (e.g. years, months, and days). We then describe our work testing the impact of patterns of parental signals on a moment-to-moment timescale, providing evidence that patterns of these signals during sensitive windows of development influence neurocircuit formation across species and thus may be an evolutionarily conserved process that shapes the developing brain. Next, attention is drawn to emerging themes which provide a framework for future directions of research including the evaluation of functions, such as effortful control, that may be particularly vulnerable to unpredictability, sensitive periods, sex differences, cross-cultural investigations, addressing causality, and unpredictability as a pathway by which other forms of ELA impact development. Finally, we provide suggestions for prevention and intervention, including the introduction of a screening instrument for the identification of children exposed to unpredictable experiences.

Childhood unpredictability research within the developmental psychopathology framework: Advances, implications, and future directions

Greater unpredictability in childhood from the level of the caregiver-child dyad to broader family, home, or environmental instability is consistently associated with disruptions in cognitive, socioemotional, behavioral, and biological development in humans. These findings are bolstered by experimental research in non-human animal models suggesting that early life unpredictability is an important environmental signal to the developing organism that shapes neurodevelopment and behavior. Research on childhood unpredictability has surged in the past several years, guided in part by theoretical grounding from the developmental psychopathology framework (shaped largely by Dr. Dante Cicchetti's innovative work). The current review focuses on future directions for unpredictability research, including probing intergenerational effects, the role of predictability in resilience, cultural and contextual considerations, and novel developmental outcomes that should be tested in relation to childhood unpredictability. We urge the integration of multidisciplinary perspectives and collaborations into future research on unpredictability. We also provide ideas for translating this research to real-world practice and policy and encourage high-quality research testing whether incorporating predictability into interventions and policy improves developmental outcomes, which would support further dissemination of these findings.

Differential longitudinal effects of frequent sweetened food consumption at different exposure ages on child cognitive, language, and motor development

BACKGROUND

Evidence reveals frequent sugar consumption worsens cognition in animal models, and similar effects on child development are probable. We aimed to investigate the influence of sweetened foods (SFs) on child developmental trajectories.

METHODS

The prospective cohort recruited 3-month-old children in Taiwan from 1st April 2016 to 30th June 2017. Developmental inventories including cognitive, language, and motor domains, were measured at the age of 3-,12-, 24-, and 36 months old via in-person interviews. We constructed latent growth models with covariates to estimate the influence of SFs on child development.

RESULTS

Ultimately, 4782 children (50.7% boys) were included in the statistical analysis. In the cognitive domain, consumption at one year of age significantly affected the intercept, but not the linear slope and quadratic term (intercept: estimate = -0.054, p < .001); consumption at two years of age significantly affected the intercept and quadratic term (intercept: estimate = -0.08, p < .001; quadratic term: estimate = -0.093, p = .026), but not the linear slope. In the language domain, only consumption at two years of age significantly affected the intercept (estimate = -0.054, p < .001). In the motor domain, consumption at two years of age significantly affected the linear slope and quadratic term (estimate = 0.080, p = .011 and estimate = -0.082, p = .048, respectively).

CONCLUSION

We found SFs exposure at different times has different negative effects on child development. Early exposure to SFs harmed children's cognitive function. Relatively late exposure to SFs not only deteriorated children's cognitive and language abilities but also decelerated developmental velocity in cognitive and motor domains.