Multimodal study of infra-slow propagating brain activity

项目摘要 高度组织化的内在大脑活动，通过静息态功能磁共振成像测量 （rsfMRI）被广泛用于测量健康受试者和患者的功能性脑连接 组，尽管潜在的神经机制仍然在很大程度上不清楚。越来越多的证据表明 超慢传播活动可能在产生rsfMRI连接性和动力学中起重要作用， 因此，它可能是理解rsfMRI连接性的神经基础和功能作用的关键。 内在的大脑活动然而，对超慢传播脑活动的研究仍然有限， 使用rsfMRI，由于特定区域的血流动力学，它面临着推断传播活动的严重问题 延误了.对亚慢传播活动缺乏明确的认识， 理解内在大脑活动的功能作用，也阻碍了rsfMRI的解释和使用- 基于连接/动态测量的各种脑部疾病。为了弥合这一关键差距， 该应用程序将联合收割机从大规模、公开可用的数据集中组合多模态数据，以充分表征 亚慢传播的大脑活动，并阐明其神经生理学基础，结构相关性， 功能相关性。研究目标将通过三个具体目标来实现。目标1： 表征并比较rsfMRI和收集的电生理信号中的亚慢传播活动 从人类和猴子身上。据推测，超慢传播活动是目前在这两个 人类rsfMRI和猴子电生理学，主要是沿着沿着一个层次轴连接较低和较高的， 顺序皮质区域。目的2是阐明亚慢繁殖活性与 各种结构/形态测量的大脑特性。假设跨层级传播活动 是紧密相连的，跨学科，以跨层次的对比，某些结构/形态特征， 并且它们都能显著解释受试者之间的行为变异性。在目标3中， 将通过其在各种大脑条件下的调制来确定超慢传播活动。是 假设跨层级传播活动在清醒和睡眠期间受到显著调制， PD患者，取决于大脑的光谱梯度，并显示出与涟漪触发大脑相似的动力学 活动拟议的研究是创新的，因为它将联合收割机多模态数据从5个独立的 数据集有一个全面的了解超慢传播活动，重点是它的交叉- 层次特征，并使用一种新的方法，设计用于检测和量化单传播 实例.这项研究的影响是重大的，因为它预计将大大推动 了解休息时消耗主要大脑能量预算的内在大脑活动， 一种新颖的基于功能相关的图像标记物，也为脑的相关层次结构提供了一种新的认识 rsfMRI连接/动力学测量广泛应用于神经科学和临床研究。

PROJECT SUMMARY The highly-organized intrinsic brain activity, as measured by resting-state functional magnetic resonance imaging (rsfMRI), is being widely used to measure functional brain connectivity in both healthy subjects and patient groups, despite the underlying neural mechanisms remain largely unclear. Converging evidence has suggested that infra-slow propagating activity may play an important role in generating rsfMRI connectivity and dynamics, and it thus could be the key to understanding the neural basis of rsfMRI connectivity and the functional role of intrinsic brain activity. However, the study of the infra-slow propagating brain activity remains limited and mostly used rsfMRI, which faces a serious issue for inferring propagating activity due to region-specific hemodynamic delays. The lack of a clear understanding of the infra-slow propagating activity has greatly hinder the understanding of functional roles of intrinsic brain activity and also hamper the interpretation and use of rsfMRI- based connectivity/dynamics measures in various brain diseases. To bridge this critical gap, the major goal of this application is to combine multimodal data from large-scale, publicly available datasets to fully characterize the infra-slow propagating brain activity and elucidate its neurophysiological basis, structural correlates, and functional relevance. The research objective will be achieved through three specific aims. Aim 1 is to characterize and compare the infra-slow propagating activity in rsfMRI and electrophysiological signals collected from both human and monkeys. It is hypothesized that the infra-slow propagating activity is present in both human rsfMRI and monkey electrophysiology, and mostly along a hierarchical axis linking the lower- and higher- order cortical regions. Aim 2 is to elucidate the relationship between the infra-slow propagating activity and various structural/morphometric brain properties. The hypothesis is that the cross-hierarchy propagating activity is closely linked, across subjects, to the cross-hierarchy contrast of certain structural/morphometric properties, and they both account significantly for inter-subject behavioral variability. In Aim 3, the functional relevance of the infra-slow propagating activity will be determined through its modulation across various brain conditions. It is hypothesized that the cross-hierarchy propagating activity is significantly modulated across wake and sleep, in PD patients, dependent on the spectral gradient of the brain, and show similar dynamics as ripple-trigger brain activity. The proposed research is innovative because it will combine multimodal data from 5 independent datasets to have a comprehensive understanding of the infra-slow propagating activity with focusing on its cross- hierarchy features and using a novel methodology designed for detecting and quantifying single propagating instances. The impact of this research is significant because it is expected to significantly advance the understanding of the intrinsic brain activity at rest that consumes the major brain energy budget, to generate novel function-related image markers based on related to brain hierarchy, and also to offer a new understanding of rsfMRI connectivity/dynamics measure widely used in neuroscience and clinical research.