Children from lower-SES families exhibit smaller hippocampal volume than do their higher-SES peers. Few studies, however, have compared hippocampal developmental trajectories as a function of SES. Thus, it is unclear whether initial rank-order stability is preserved, or whether volumes diverge/converge over the course of adolescence. In a sample of 101 girls ages 10–24 years, we examined the longitudinal association between family income and parental education, proxies for SES, and changes in hippocampal volume. Hippocampal volume was obtained using MRI; using mixed modeling, we examined the effects of income and education on hippocampal volume across age. As expected, changes in volume were non-linear across development. Further, trajectories diverged in mid-adolescence, with lower-income girls exhibiting reductions in hippocampal volume. Maximal income-related differences were observed at 18 years, and trajectories converged thereafter. This interaction remained significant when accounting for maternal hippocampal volume, suggesting a unique contribution of environment over potential heritable differences. In contrast, the association between parental education and offspring hippocampal volume appeared to be stable across adolescence, with higher levels of parental education predicting consistently larger hippocampal volume. These findings constitute preliminary evidence that girls from lower-income homes exhibit unique trajectories of hippocampal growth, with differences most evident in late adolescence.

Prior research indicates that lower resting-state functional coupling between two brain networks, lateral frontoparietal network (LFPN) and default mode network (DMN), relates to cognitive test performance, for children and adults. However, most of the research that led to this conclusion has been conducted with non-representative samples of individuals from higher-income backgrounds, and so further studies including participants from a broader range of socioeconomic backgrounds are required. Here, in a pre-registered study, we analyzed resting-state fMRI from 6839 children ages 9–10 years from the ABCD dataset. For children from households defined as being above poverty (family of 4 with income > $25,000, or family of 5+ with income > $35,000), we replicated prior findings; that is, we found that better performance on cognitive tests correlated with weaker LFPN-DMN coupling. For children from households defined as being in poverty, the direction of association was reversed, on average: better performance was instead directionally related to stronger LFPN-DMN connectivity, though there was considerable variability. Among children in households below poverty, the direction of this association was predicted in part by features of their environments, such as school type and parent-reported neighborhood safety. These results highlight the importance of including representative samples in studies of child cognitive development.

Background: Dysfunctional reward processing is a core feature of major depressive disorder. While there is growing knowledge of reward processing in adolescent depression, researchers have ignored neural mechanisms of resilience to depression. Here, we examine neural correlates of reward processing that characterize resilience and risk in adolescents at risk for depression, facilitating the development of effective intervention approaches that strengthen resilience to psychopathology in at-risk youth. Methods: 50 adolescent females were followed through age 18: 32 at-risk adolescents who either did (remitted-depressed; n=15) or did not (resilient; n=17) experience a depressive episode, and 18 low-risk healthy controls. Participants completed clinical assessments at 18-month intervals and an fMRI reward-processing task in late adolescence. We conducted predictive modeling with a priori reward regions of interest (ROIs). Results: At-risk resilient and remitted-depressed adolescents exhibited less striatal activation than did controls during anticipation of reward. Resilient adolescents exhibited greater activation than did remitted-depressed adolescents in the middle frontal gyrus, and less activation in the superior frontal gyrus and cuneus during reward processing. Using predictive modeling, ventral anterior cingulate cortex and putamen activation during reward processing distinguished resilient from remitted-depressed adolescents with 83% accuracy.

The CEGA Working Paper Series showcases ongoing and completed research by faculty affiliates of the Center. CEGA Working Papers employ rigorous evaluation techniques to measure the impact of large-scale social and eco-nomic development programs, and are intended to encourage discussion and feedback from the global development community.

Empirical audit and review is an approach to assessing the evidentiary value of a research area. It involves identifying a topic and selecting a cross-section of studies for replication. We apply the method to research on the psychological consequences of scarcity. Starting with the papers citing a seminal publication in the field, we conducted replications of 20 studies that evaluate the role of scarcity priming in pain sensitivity, resource allocation, materialism, and many other domains. There was considerable variability in the replicability, with some strong successes and other undeniable failures. Empirical audit and review does not attempt to assign an overall replication rate for a heterogeneous field, but rather facilitates researchers seeking to incorporate strength of evidence as they refine theories and plan new investigations in the research area. This method allows for an integration of qualitative and quantitative approaches to review and enables the growth of a cumulative science.