Child Psychiatry Branch, National Institute of Mental Health, Bethesda, Maryland 20892, USA.
J Neurosci. 2011 May 11;31(19):7174-7. doi: 10.1523/JNEUROSCI.0054-11.2011.
Understanding human cortical maturation is a central goal for developmental neuroscience. Significant advances toward this goal have come from two recent strands of in vivo structural magnetic resonance imaging research: (1) longitudinal study designs have revealed that factors such as sex, cognitive ability, and disease are often better related to variations in the tempo of anatomical change than to variations in anatomy at any one time point; (2) largely cross-sectional applications of new surface-based morphometry (SBM) methods have shown how the traditional focus on cortical volume (CV) can obscure information about the two evolutionarily and genetically distinct determinants of CV: cortical thickness (CT) and surface area (SA). Here, by combining these two strategies for the first time and applying SBM in >1250 longitudinally acquired brain scans from 647 healthy individuals aged 3-30 years, we deconstruct cortical development to reveal that distinct trajectories of anatomical change are hidden within, and give rise to, a curvilinear pattern of CV maturation. Developmental changes in CV emerge through the sexually dimorphic and age-dependent interaction of changes in CT and SA. Moreover, SA change itself actually reflects complex interactions between brain size-related changes in exposed cortical convex hull area, and changes in the degree of cortical gyrification, which again vary by age and sex. Knowing of these developmental dissociations, and further specifying their timing and sex-biases, provides potent new research targets for basic and clinical neuroscience.
理解人类皮质成熟是发展神经科学的一个核心目标。最近两项活体结构磁共振成像研究为实现这一目标提供了重要进展：（1）纵向研究设计表明，性别、认知能力和疾病等因素通常与解剖变化速度的变化更为相关，而不是与任何一个时间点的解剖变化更为相关；（2）新的基于表面形态计量学（SBM）方法的广泛横截面应用表明，传统上对皮质体积（CV）的关注如何掩盖了关于 CV 的两个进化和遗传上不同决定因素的信息：皮质厚度（CT）和表面积（SA）。在这里，我们首次将这两种策略结合起来，并在 647 名年龄在 3 至 30 岁的健康个体的 1250 多次纵向获得的脑扫描中应用 SBM，我们对皮质发育进行了解构，揭示了 CV 成熟的曲线模式中隐藏着并产生了不同的解剖变化轨迹。CV 的发育变化是通过 CT 和 SA 的性别二态性和年龄依赖性变化相互作用而出现的。此外，SA 的变化本身实际上反映了暴露的皮质凸壳区域的脑大小相关变化与皮质回旋度变化之间的复杂相互作用，而这些变化又因年龄和性别而异。了解这些发育差异，并进一步确定其时间和性别偏见，为基础和临床神经科学提供了新的研究目标。
