The human brain is highly dynamic, supporting a remarkable range of cognitive abilities that emerge over the course of development. While flexible and dynamic coordination between different neural systems is firmly established for children, our understanding of brain functional organization in early life has been built largely on the implicit assumption that functional connectivity (FC) is static. Understanding the nature of dynamic neural interactions during development is a critical issue for cognitive neuroscience, with implications for neurodevelopmental pathologies that involve anomalies in brain connectivity. In this work, we delineate FC dynamics of neurocognitive networks in a sample of 146 youth from varied sociodemographic backgrounds. We apply independent component analysis, sliding time window correlation, and k-means clustering to resting-state fMRI data. Our analyses revealed six FC states that re-occur over time and that complement, but significantly extend, measures of static connectivity averaged across the experiment. Moreover, the occurrence and amount of time spent in specific FC states are related to the content of self-generated thought during the scan. We also found age-related increases in temporal variability of FC among neurocognitive networks. In addition, some connections are more variable over time than are others, including those between inferior parietal lobe and precuneus. These regions contribute to multiple large-scale systems and likely play a role in adaptive processes in early life. Taken together, these findings lay the groundwork for understanding how variation in the developing chronnectome is related to risk for neurodevelopmental disorders. Understanding how brain systems reconfigure with development should provide insight into the ontogeny of complex, flexible cognitive processes in adulthood.

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Socioeconomic disadvantage (SED) experienced in early life is linked to a range of risk behaviors and diseases. Neuroimaging research indicates that this association is mediated by functional changes in corticostriatal reward systems that modulate goal-directed behavior, reward evaluation, and affective processing. Existing research has focused largely on adults and within-household measures as an index of SED, despite evidence that broader community-level SED (e.g., neighborhood poverty levels) has significant and sometimes distinct effects on development and health outcomes. Here, we test effects of both household- and community-level SED on resting-state functional connectivity (rsFC) of the ventral striatum (VS) in 100 racially and economically diverse children and adolescents (ages 6-17). We observed unique effects of household income and community SED on VS circuitry such that higher community SED was associated with reduced rsFC between the VS and an anterior region of the medial prefrontal cortex (mPFC), whereas lower household income was associated with increased rsFC between the VS and the cerebellum, inferior temporal lobe, and lateral prefrontal cortex. Lower VS-mPFC rsFC was also associated with higher self-reported anxiety symptomology, and rsFC mediated the link between community SED and anxiety. These results indicate unique effects of community-level SED on corticostriatal reward circuitry that can be detected in early life, which carries implications for future interventions and targeted therapies. In addition, our findings raise intriguing questions about the distinct pathways through which specific sources of SED can affect brain and emotional development.

Given the potential negative effects that early childhood behavioral problems have on later development, it is important to elucidate risk and protective factors. This study examined household chaos as a predictor of externalizing and internalizing problems among young children from low-income families. Additionally, self-regulation was examined as a moderator of the association between chaos and behavior problems. One hundred young adult mother-toddler dyads participated. Moderation analyses indicated that self-regulation buffered the association between household chaos and child behavior problems. Specifically, greater household chaos was associated with more behavior problems, but only among children with poorer self-regulation. Notably, this pattern was observed for both externalizing and internalizing problems. These findings suggest that early interventions targeting young children’s self-regulation skills could help prevent behavior problems among children living in chaotic home environments.