Global Signal Correction in Resting State fMRI

静息态 fMRI 中的全局信号校正

• 批准号: 8258622
• 负责人: THOMAS T LIU
• 金额: $ 23.22万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-27 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8258622
• 关键词: Adopted; Agreement; Brain; Brain region; Cardiac; Characteristics; Collection; Consensus; Data; Data Set; Dependence; Development; Disease; Electroencephalography; Functional Magnetic Resonance Imaging; Future; Goals; Health; Human; Knowledge; Magnetic Resonance Imaging; Maps; Measures; Methods; Metric; Modality; Performance; Physiological; Process; Rest; Series; Short-Term Memory; Signal Transduction; Source; Testing; Theoretical Studies; Time; United States National Institutes of Health; Variant; Work; base; clinical application; design; improved; interest; novel strategies; relating to nervous system; research study; respiratory; standard measure

DESCRIPTION (provided by applicant): Resting-state functional connectivity magnetic resonance imaging (fcMRI) has recently emerged as a leading method for non-invasively characterizing the functional connections of the human brain. In fcMRI studies, a standard measure of connectivity between two brain regions is the temporal correlation between their respective resting-state functional MRI (fMRI) time series. For the computation of correlations, many studies use a pre-processing step known as global signal regression (GSR), in which a global mean signal is subtracted from all voxel time courses. While GSR can greatly improve the consistency and reliability of functional connectivity maps, its use is controversial because it may also introduce spurious negative correlations. Currently, there is not a clear consensus regarding how to best handle global signal confounds, with many fcMRI studies still continuing to use GSR, while others have adopted alternate methods due to concerns about GSR. This lack of agreement makes it difficult to compare fcMRI studies, as differing approaches can yield significantly different connectivity measures. The goals of this project are to develop a better understanding of the global signal and to use that knowledge to develop new methods for global signal correction. The aims of the study are to (1) Develop and evaluate a new approach for global signal correction and (2) Determine whether global signal variations reflect changes in underlying neuroelectric coherence. PUBLIC HEALTH RELEVANCE: The proposed project will improve our ability to accurately measure functional connections in the brain using resting-state fMRI. Because the strength of functional connections may be an important indicator of the health of the brain, the proposed methods will benefit the study of a wide range of diseases.

描述（由申请人提供）：静息状态功能连接磁共振成像（fcMRI）最近已经成为非侵入性表征人脑功能连接的主要方法。在fcMRI研究中，两个大脑区域之间连接性的标准测量是它们各自的静息状态功能MRI（fMRI）时间序列之间的时间相关性。对于相关性的计算，许多研究使用称为全局信号回归（GSR）的预处理步骤，其中从所有体素时间过程中减去全局平均信号。虽然GSR可以大大提高功能连接图的一致性和可靠性，但它的使用是有争议的，因为它也可能引入虚假的负相关。目前，关于如何最好地处理全局信号混淆还没有明确的共识，许多fcMRI研究仍然继续使用GSR，而其他研究则由于对GSR的担忧而采用了替代方法。这种缺乏一致性使得很难比较fcMRI研究，因为不同的方法可以产生显着不同的连接措施。该项目的目标是更好地了解全球信号，并利用这些知识开发全球信号校正的新方法。该研究的目的是（1）开发和评估全局信号校正的新方法，以及（2）确定全局信号变化是否反映了潜在神经电一致性的变化。 公共卫生相关性：该项目将提高我们使用静息态功能磁共振成像准确测量大脑功能连接的能力。由于功能连接的强度可能是大脑健康的一个重要指标，因此所提出的方法将有利于研究各种疾病。