Abstract:
Cortical thickness varies throughout the cortex in a systematic way. However, it is challenging to investigate the patterns of cortical thickness due to the intricate geometry of the cortex. The cortex has a folded nature both in radial and tangential directions which forms not only gyri and sulci but also tangential folds and intersections. In this article, cortical curvature and depth are used to characterize the spatial distribution of the cortical thickness with much higher resolution than conventional regional atlases. To do this, a computational pipeline was developed that is capable of calculating a variety of quantitative measures such as surface area, cortical thickness, curvature (mean curvature, Gaussian curvature, shape index, intrinsic curvature index, and folding index), and sulcal depth. By analyzing 501 neurotypical adult human subjects from the ABIDE-I dataset, we show that cortex has a very organized structure and cortical thickness is strongly correlated with local shape. Our results indicate that cortical thickness consistently increases along the gyral-sulcal spectrum from concave to convex shape, encompassing the saddle shape along the way. Additionally, tangential folds influence cortical thickness in a similar way as gyral and sulcal folds; outer folds are consistently thicker than inner.
摘要:
皮质厚度在整个皮质中以系统的方式变化。然而,由于皮质复杂的几何形状,研究皮质厚度的模式是具有挑战性的。皮质在径向和切向方向上都具有折叠性质,不仅形成回旋和沟,而且还形成切向折叠和相交。在这篇文章中,皮质曲率和深度用于表征皮质厚度的空间分布,分辨率比常规区域图集高得多。要做到这一点,开发了一种计算管道,能够计算各种定量测量,如表面积,皮质厚度,曲率(平均曲率,高斯曲率,形状指数,固有曲率指数,和折叠指数),和沟深。通过分析来自ABIDE-I数据集的501名神经典型的成年人受试者,我们表明皮质具有非常有组织的结构,皮质厚度与局部形状密切相关。我们的结果表明,皮质厚度沿着回旋沟光谱从凹形到凸形一致增加,沿途包含马鞍形状。此外,切向褶皱以与回旋和沟褶皱相似的方式影响皮质厚度;外部褶皱始终比内部褶皱厚。