Functional MRI investigation of spinal cord resting-state networks and their physiological relevance

静息状态的功能性磁共振成像（fMRI）研究提供了大量关于皮质功能的信息，我实验室的研究已经将这种能力扩展到脑干（BS）和脊髓（SC）。静息状态功能磁共振成像研究指的是在没有任务或刺激的情况下发生的协调血氧水平依赖（BOLD）反应，因此神经活动与内部定向认知相对应。我的实验室已经获得的证据表明，在休息状态下，SC中的协调信号可能与SC兴奋性的下降调节有关，通过BS。因此，静息状态协调的概念扩展到整个中枢神经系统，以及认知以外的功能。 到目前为止，我实验室的研究已经证明了fMRI数据中生理噪声的主要来源，它们的相对贡献以及如何减少/消除它们。这使我们能够确认，有广泛的协调内和跨BS和SC地区在休息状态，并开始调查这种协调是如何改变认知过程。 这项研究的目标是：1）进一步了解人类SC神经生理学以及功能如何在持续的基础上进行调节，2）开发用于识别和研究这种调节的分析工具。具体目标是： 目标1：根据区域和连接、发生率和连接强度，表征BS和SC上处于静止状态的协调信令的一致网络。 目标二：确定健康人群中rs网络的变化，以及静息状态连接与各种功能之间的关系（基于先前的研究），包括：1）疼痛敏感性，2）与心脏和呼吸功能相关的运动活动，3）自主调节。 目标3：开发和验证用于BS和SC中静息状态分析结果分析和可视化的软件工具。 拟议的研究将为大约6名研究生提供丰富的培训机会，以及本科论文项目，并将有助于我们对健康人体中BS和SC功能的全面了解。它还将改进我们现有的研究工具。预计对这些网络/系统及其持续调节的理解将支持未来的研究，以更好地了解各种疾病的影响和伤害的影响。持续的静息状态功能可能是维持许多系统稳态的核心，因此可能是我们生理学的一个非常重要的特征。因此，拟议中的研究有可能对我们理解涉及脑干和脊髓的所有功能产生重大影响。

Functional magnetic resonance imaging (fMRI) studies of the resting-state have provided a wealth of information about cortical function, and research in my lab has extended this capability to the brainstem (BS) and spinal cord (SC). Resting-state fMRI studies refer to coordinated blood oxygenation-level dependent (BOLD) responses that occur when no task or stimulus is applied, and therefore the neural activity corresponds with internally-directed cognition. My lab has obtained evidence that coordinated signaling in the SC, in the resting-state, is likely related to descending regulation of SC excitability, via the BS. The concept of resting-state coordination thus extends to the entire central nervous system, and to functions other than cognition. Research in my lab to date has demonstrated the primary sources of physiological noise in fMRI data, their relative contributions, and how to reduce/remove them. This enabled us to confirm that there is extensive coordination within and across BS and SC regions in the resting-state, and to begin to investigate how this coordination is altered by cognitive processes. The proposed research has the goals of 1) furthering our understanding of human SC neurophysiology and how function is regulated on a continuous basis, and 2) developing analysis tools for identifying and studying this regulation. The specific objectives are: Objective 1: Characterize the consistent networks of coordinated signaling in the resting-state across the BS and SC, in terms of regions and connections, rates of occurrence, and connection strengths. Objective 2: Identify variations in rs-networks across healthy people, and the relationships between resting-state connectivity and various functions (based on prior research), including; 1) pain sensitivity, 2) motor activity related to cardiac and respiratory function, 3) autonomic regulation. Objective 3: Develop and validate software tools for analysis and visualization of results for resting-state analyses in the BS and SC. The proposed research will provide a wealth of training opportunities for approximately 6 graduate students, as well as undergraduate thesis projects, and will contribute to our overall understanding of BS and SC function in healthy humans. It will also improve the tools we have available to do this research. It is expected that an understanding of these networks/systems and their continuous regulation will support future research into better understanding the effects of a wide variety of diseases and effects of injuries. Continuous resting-state function may be central to maintaining homeostasis of a number of systems and therefore may be a very important feature of our physiology. The proposed research thus has the potential for significant impact on our understanding of all functions that involve the brainstem and spinal cord.