The role of brain arousal in resting-state functional MRI

项目摘要 静息状态功能磁共振成像(Rsfmri)正被广泛地应用于 健康受试者和患者组大规模脑网络的功能连通性和动力学， 尽管基于rsfMRI的连接性/动力学测量具有神经基础，但在很大程度上仍不清楚。融合 有证据表明，考虑到rsfmri的巨大变化，唤醒相关因素的贡献。 然而，对唤醒因素在rsfmri研究中的作用的系统理解是不同的大脑状态。 失踪。这种知识的缺乏阻碍了对rsfmri的正确解释和正确使用。 测量大脑的连通性和动力学。为了弥合这一关键差距，此应用程序的主要目标是 开发一种基于时空fMRI动力学的觉醒测量方法，并用它来阐明和控制 觉醒对基于rsfmri的大脑连接性和动力学测量的影响。这项研究 目标将通过三个具体目标来实现。目标1是绘制时空功能磁共振成像动力学图 最近发现的觉醒调节事件，并利用该信息来改善基于fMRI的 唤醒措施。工作假设是，短暂的觉醒调制与特定的 FMRI激活序列，并且这种时空动态可以被用来极大地改进基于fMRI的 性唤醒测量。目的2是评估与觉醒相关的功能磁共振改变对这种关系的贡献 RsfMRI连接和非神经元信号之间的关系，包括生理信号和头部运动。它是 假设觉醒调节在rsfMRI连接性和 非神经性噪音。在目标3中，唤醒因素对基于rsfMRI的脑定量的贡献 将评估动力学及其与行为测量的相关性。工作假说是， 唤醒效应对rsfmri动力学的影响可以分解为具有优势的“状态”效应和“特质”效应。 分别对感觉/运动脑区和高级认知网络产生影响。唤醒的“特质” 与唤醒调节的内在个体差异有关的部分相关 Rsfmri动力学和人类行为方面。拟议的研究具有创新性，因为它将结合 局部实验和大数据分析系统研究觉醒调制对rsfMRI的直接影响 连通性和动力学，以及调节它们与生理学和 行为。它还将专注于瞬间唤醒调制下的时空大脑动力学，并利用这一点 基于功能磁共振成像的唤醒测量的信息。这项研究的影响是重大的，因为 了解觉醒对基于rsfMRI的连接性/动力学测量的影响对于 正确解释和正确使用这些指标。基于功能磁共振成像的准确的唤醒测量不仅是 对控制唤醒效应，从而改进基于rsfMRI的量化很重要，而且对未来也很重要 对唤醒及其在各种脑部疾病中的作用感兴趣的神经成像研究。

Project Summary Resting-state functional magnetic resonance imaging (rsfMRI) is being widely used to measure functional connectivity and dynamics of large-scale brain networks in both healthy subjects and patient groups, despite the neural bases of rsfMRI-based connectivity/dynamics measures remain largely unclear. Converging evidence has suggested the contributions from arousal-related factors given large rsfMRI changes seen across distinct brain states, however, a systemic understanding of the role of arousal factors in rsfMRI research is missing. The lack of this knowledge hampers the correct interpretation and proper use of rsfMRI-based measures of brain connectivity and dynamics. To bridge this critical gap, the major goal of this application is to develop an arousal measure based on spatiotemporal fMRI dynamics and then use it to elucidate and control for the influences of the arousal on rsfMRI-based measures of brain connectivity and dynamics. The research objective will be achieved through three specific aims. Aim 1 is to map spatiotemporal fMRI dynamics associated with a recently discovered event of arousal modulation and utilize this information to improve fMRI-based arousal measure. The working hypothesis is that transient arousal modulations are associated with a specific sequence of fMRI activations, and this spatiotemporal dynamic can be utilized to greatly improve fMRI-based arousal measurements. Aim 2 is to assess the contribution of arousal-related fMRI changes to the relationship between rsfMRI connectivity and non-neuronal signals, including physiological signals and head motions. It is hypothesized that the arousal modulation mediates spurious relationships between rsfMRI connectivity and the non-neuronal noise. In Aim 3, the contributions of arousal factors to rsfMRI-based quantifications of brain dynamics and their correlations with behavioral measures will be assessed. The working hypothesis is that the arousal effects on rsfMRI dynamics can be decomposed into the “state” and “trait” effects that have preferential impacts on the sensory/motor brain areas and higher-order cognitive networks respectively. The arousal “trait” related to intrinsic individual difference in arousal regulation mediates a part of correlations between certain aspects of rsfMRI dynamics and human behavior. The proposed research is innovative because it will combine local experiments and big data analyses to systemically study the direct effect of arousal modulations on rsfMRI connectivity and dynamics, as well as indirect effects of mediating their correlations with physiology and behavior. It will also focus on spatiotemporal brain dynamics at transient arousal modulations and utilize this information for an fMRI-based arousal measure. The impact of this research is significant because a clear understanding of the effects of the arousal on rsfMRI-based connectivity/dynamics measures is critical for proper interpretation and correct use of these metrics. An accurate fMRI-based arousal measure is not only important for controlling the arousal effects and thus improve rsfMRI-based quantifications but also for future neuroimaging studies that are interested in the arousal and its role in various brain diseases.