Children born very preterm experience altered cortical expansion over the first decade of life.

The brain develops rapidly from the final trimester of gestation through childhood, with cortical surface area expanding greatly in the first decade of life. However, it is unclear exactly where and how cortical surface area changes after birth, or how prematurity affects these developmental trajectories. Fifty-two very preterm (gestational age at birth = 26 ± 1.6 weeks) and 41 full-term (gestational age at birth = 39 ± 1.2 weeks) infants were scanned using structural magnetic resonance imaging at term-equivalent age and again at 9/10 years of age. Individual cortical surface reconstructions were extracted for each scan. Infant and 9/10 cortical surfaces were aligned using anatomically constrained Multimodal Surface Matching (aMSM), a technique that allows calculation of local expansion gradients across the cortical surface for each individual subject. At the neonatal time point, very preterm infants had significantly smaller surface area than their full-term peers (P < 0.001), but at the age 9/10-year time point, very preterm and full-term children had comparable surface area (P > 0.05). Across all subjects, cortical expansion by age 9/10 years was most pronounced in frontal, temporal, and supramarginal/inferior parietal junction areas, which are key association cortices (P Spin < 0.001). Very preterm children showed greater cortical surface area expansion between term-equivalent age and age 9/10 compared to their full-term peers in the medial and lateral frontal areas, precuneus, and middle temporal/banks of the superior sulcus junction (P < 0.05). Furthermore, within the very preterm group, expansion was highly variable within the orbitofrontal cortex and posterior regions of the brain. By mapping these patterns across the cortex, we identify differences in association cortices that are known to be important for executive functioning, emotion processing, and social cognition. Additional longitudinal work will be needed to understand if increased expansion in very preterm children is adaptive, or if differences persist into adulthood.

Neighborhood Crime and Externalizing Behavior in Toddlers: A Longitudinal Study With Neonatal fMRI and Parenting.

OBJECTIVE: Prenatal exposure to neighborhood crime has been associated with weaker neonatal frontolimbic connectivity; however, associations with early childhood behavior remain unclear. We hypothesized that living in a high-crime neighborhood would be related to higher externalizing symptoms at age 1 and 2 years, over and above other adversities, and that neonatal frontolimbic connectivity and observed parenting behaviors at 1 year would mediate this relationship. METHOD: Participants included 399 pregnant women, recruited as part of the Early Life Adversity, Biological Embedding, and Risk for Developmental Precursors of Mental Disorders (eLABE) study. Geocoded neighborhood crime data was obtained from Applied Geographic Solution. A total of 319 healthy, non-sedated neonates underwent scanning using resting-state functional magnetic resonance imaging (fMRI) on a Prisma 3T scanner and had ≥10 minutes of high-quality data. Infant-Toddler Socioemotional Assessment Externalizing T scores were available for 274 mothers of 1-year-olds and 257 mothers of 2-year-olds. Observed parenting behaviors were available for 202 parent-infant dyads at 1 year. Multilevel and mediation models tested longitudinal associations. RESULTS: Living in a neighborhood with high violent (ß = 0.15, CI = 0.05-0.27, p = .004) and property (ß = 0.10, CI = 0.01-0.20, p = .039) crime was related to more externalizing symptoms at 1 and 2 years, controlling for other adversities. Weaker frontolimbic connectivity was also associated with higher externalizing symptoms at 1 and 2 years. After controlling for other adversities, parenting behaviors mediated the specific association between crime and externalizing symptoms, but frontolimbic connectivity did not. CONCLUSION: These findings provide evidence that early exposure to neighborhood crime and weaker neonatal frontolimbic connectivity may influence later externalizing symptoms, and suggest that parenting may be an early intervention target for families in high-crime areas. DIVERSITY & INCLUSION STATEMENT: We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented sexual and/or gender groups in science. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.