Multimodal study of infra-slow propagating brain activity

项目总结 通过静息状态功能磁共振成像测量的高度组织化的内在大脑活动 (RsfMRI)，正被广泛用于测量健康受试者和患者的脑功能连接 尽管潜在的神经机制在很大程度上仍不清楚。汇集的证据表明 次慢传播活动可能在产生rsfMRI连通性和动力学方面发挥重要作用， 因此，这可能是理解rsfmri连接的神经基础和rsfmri的功能作用的关键。 大脑的内在活动。然而，对次慢传播性脑活动的研究仍然有限，而且主要是 使用rsfmri，由于区域特定的血流动力学，这在推断传播活动方面面临严重的问题。 耽搁了。对亚慢速传播活动缺乏清晰的认识，极大地阻碍了 了解脑内固有活动的功能作用，也阻碍了对rsfMRI的解释和使用- 基于各种脑部疾病的连通性/动力学测量。为了弥合这一关键差距， 此应用程序将结合来自大规模、公开可用的数据集的多模式数据，以充分表征 亚慢传播性脑活动，并阐明其神经生理学基础、结构相关性和 功能相关性。研究目标将通过三个具体目标来实现。目标1是 描述和比较rsfMRI和电生理信号中的次慢传播活动 从人类和猴子身上。假设亚低速传播活动在这两种情况下都存在 人类rsfMRI和猴子的电生理学，主要沿着连接较低和较高的- 对皮质区域进行排序。目的2是为了阐明亚慢速繁殖活动与 各种结构/形态计量学的大脑特性。假设是跨层次的传播活动 跨受试者与某些结构/形态测量属性的跨层次对比密切相关， 它们都是受试者间行为差异的重要原因。在目标3中，功能相关性 次慢传播活动将通过它在各种大脑条件下的调节来确定。它是 假设跨层次的传播活动在觉醒和睡眠之间受到显著调制，在 帕金森病患者依赖于大脑的光谱梯度，并表现出与涟漪触发脑相似的动力学 活动。拟议的研究具有创新性，因为它将结合来自5个独立的 数据集，以全面了解次慢传播活动，重点是它的交叉 层次结构特征，并使用一种新的方法来检测和量化单次传播 实例。这项研究的影响是重大的，因为它预计将显著推动 了解静止时的内在大脑活动，它消耗主要的大脑能量预算，以产生 新的功能相关图像标记物基于相关的大脑层次，也提供了新的理解 RsfMRI连接性/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.