Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany.
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, USA.
Neuroimage. 2019 Aug 15;197:668-676. doi: 10.1016/j.neuroimage.2019.03.024. Epub 2019 Mar 20.
Technological advancements in fMRI have afforded the opportunity to conduct submillimeter investigations into human brain function. The ability to do cortical depth dependent (or layer-specific) fMRI could allow probing intrinsic neuronal organizations and inter-connections, including the directionality of interregional information flow, while ultimately shedding light on uniquely human behaviors. The methodological development and applications of cortical depth dependent fMRI has been ongoing for nearly a decade, yet a consensus on protocols, analysis pipelines and interpretations of data has yet to be reached. In this article we discuss the current status and understandings of high resolution fMRI data and methods. In particular, the spatial signal characteristics of the BOLD contrast are examined in relation to the intra-cortical vasculature and associated underlying contrast mechanisms for three pulse sequences used in laminar fMRI: gradient echo (GE), spin echo (SE) and 3D-GRASE. We conclude with a short overview of factors to be taken into account when designing a specific study, including the choice of pulse sequence, experimental design, and data analysis strategy.
功能磁共振成像（fMRI）技术的进步为研究人类大脑功能提供了亚毫米级的研究机会。进行皮质深度依赖（或层特异性）功能磁共振成像的能力可以探测内在神经元组织和连接，包括区域间信息流的方向性，从而最终揭示独特的人类行为。皮质深度依赖 fMRI 的方法学发展和应用已经进行了近十年，但在协议、分析流程和数据解释方面尚未达成共识。本文讨论了高分辨率 fMRI 数据和方法的现状和理解。特别是，检查了梯度回波（GE）、自旋回波（SE）和用于层状 fMRI 的 3D-GRASE 三种脉冲序列的 BOLD 对比的空间信号特征与皮质内血管和相关潜在对比机制之间的关系。最后简要概述了在设计特定研究时需要考虑的因素，包括脉冲序列的选择、实验设计和数据分析策略。
