Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.05.29.124297v1?rss=1 Authors: Ellwood-Lowe, M. E., Whitfield-Gabrieli, S., Bunge, S. A. Abstract: Prior fMRI research indicates that lower resting-state functional connectivity between two specific brain networks is linked to better cognitive test performance in children and adults. However, most study samples are skewed towards higher-socioeconomic status individuals---and what is adaptive for one population may not be for another. In a pre-registered study, we analyzed resting-state fMRI data from 6839 children ages 9-10 years. For children above the federal poverty line, we replicated the prior finding: better cognitive performance was related to weaker connectivity between the lateral frontoparietal and default mode networks. However, for children living in poverty, this relation trended in the opposite direction. Follow-up cross-validated predictive analyses revealed that these results were driven by several key features of a child's environment. Thus, "optimal" brain function depends in part on the external pressures children face, highlighting the need for more diverse samples in research on the human brain and behavior. Copy rights belong to original authors. Visit the link for more info