Individual differences in general cognitive ability have been associated with various brain structure metrics. A relatively novel metric referred to as pericortical Gray-White Contrast (GWC) describes the sharpness of the pericortical gray-white boundary. GWC, which is hypothesized to be at least partly influenced by the degree to which myelinated axons invade the lower layers of cortex, is believed to be significantly associated with the dynamics of signal transmission across the brain and hence, with cognitive ability. The current work explores the association between GWC and IQ across the surface of the cortex. Subject data were retrieved from the NIH MRI Study of Normal Brain Development (Evans & Brain Development Cooperative, 2006). 376 subjects with a total of 742 scans were included in the longitudinal analyses. Mixed-effects regression analyses were used to map the relation between cortical contrast and each of full-scale, performance, and verbal IQ derived from the Wechsler Abbreviated Scale of Intelligence, while covarying for scanner, sex, and age effects. Significant associations were shown with FSIQ, PIQ, but not VIQ. We discuss the interpretation of these results and how they may relate to previously published results on structural cortical associations.

一般认知能力的个体差异与各种大脑结构指标有关。一种称为皮层灰白对比度 (GWC) 的相对新颖的指标描述了皮层灰白边界的清晰度。GWC 被假设至少部分受到有髓轴突侵入皮层下层的程度的影响，它被认为与跨大脑的信号传输动力学显着相关，因此与认知能力密切相关。目前的工作探索了整个皮层表面的 GWC 和 IQ 之间的关联。受试者数据取自 NIH MRI Study of Normal Brain Development (Evans & Brain Development Cooperative, 2006)。纵向分析包括 376 名受试者，共计 742 次扫描。混合效应回归分析用于绘制皮质对比度与源自韦氏智能简写量表的全面、表现和言语智商之间的关系，同时对扫描仪、性别和年龄效应进行协变。与 FSIQ、PIQ 相关，但与 VIQ 无关。我们讨论了对这些结果的解释以及它们如何与先前发表的关于结构皮层关联的结果相关联。