OBJECTIVE Investigation of neurobiological differences between internalizing and externalizing symptoms in children is needed to better understand the unique pathophysiology of each, which may ultimately better target treatments and interventions. Longitudinal studies are critical, given the marked brain development that occurs in childhood; however, few such studies exist, and results are inconsistent. The aim of this study was to longitudinally investigate associations between internalizing and externalizing symptoms, and cortical thinning during late childhood. METHOD Participants were 105 children (49 male) from the community, who underwent magnetic resonance imaging (MRI) brain scans, and completed questionnaire measures of depressive and anxiety symptoms at two time points (mean age: 8.4 years at baseline, 10.0 years at follow-up); and, mothers, who reported on child internalizing and externalizing symptoms at both time points. Whole-brain vertex-wise regression analyses were performed to assess associations between change in cortical thickness and symptoms between baseline and follow-up. RESULTS Increases in internalizing symptoms over time were associated with reduced thinning in the orbitofrontal cortex, whereas increases in externalizing symptoms were associated with reduced thinning in the postcentral gyrus. The interaction between internalizing and externalizing symptom change was not associated with cortical thinning. CONCLUSION Results suggest that the development of internalizing and externalizing symptoms are associated with unique neurodevelopmental patterns in late childhood, potentially implicating differential deficits in affective reactivity, emotion regulation, and social cognition. Further research is required to elucidate the implications of these patterns for ongoing brain development, psychopathology, and behavior.

中文翻译：

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内化和外化症状与儿童晚期皮质发育的不同轨迹有关。

目的需要调查儿童内在和外在症状之间的神经生物学差异，以更好地了解每种疾病的独特病理生理，最终可能更好地针对治疗和干预措施。考虑到儿童时期明显的大脑发育，纵向研究至关重要。但是，这样的研究很少，结果也不一致。这项研究的目的是纵向研究内在和外在症状与儿童晚期皮质变薄之间的关联。方法参与者为社区的105名儿童（49名男性），他们接受了磁共振成像（MRI）脑部扫描，并在两个时间点完成了抑郁和焦虑症状的问卷调查（平均年龄：基线为8.4岁，随访为10.0岁） -向上）; 和，母亲，他们在两个时间点都报告了孩子的内在和外在症状。进行全脑顶点回归分析以评估皮层厚度变化与基线和随访之间症状之间的关联。结果随着时间的推移，内在症状的增加与眶额皮质的减薄有关，而外在症状的增加与中枢后回的减薄有关。内在和外在症状改变之间的相互作用与皮层变薄无关。结论结果表明，内在和外在症状的发展与儿童晚期独特的神经发育模式有关，可能暗示情感反应，情绪调节，和社会认知。需要进一步的研究来阐明这些模式对正在进行的大脑发育，精神病理学和行为的影响。