Neurophysiological Basis of fMRI

fMRI 的神经生理学基础

• 批准号: 6631105
• 负责人: CHARLES E SCHROEDER
• 金额: $ 47.04万
• 依托单位: NATHAN S. KLINE INSTITUTE FOR PSYCH RES
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-05 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6631105
• 关键词: Macaca mulatta; action potentials; behavior test; brain electrical activity; electrophysiology; evoked potentials; functional magnetic resonance imaging; hemodynamics; histology; neurochemistry; neurophysiology; neuroregulation; pharmacology; respiratory oxygen; somesthetic sensory cortex

DESCRIPTION (provided by applicant): Functional magnetic resonance imaging (fMRI) promises to provide the ability to pinpoint and track brain activity patterns underlying sensory, motor and cognitive skills, during their normal operation in intact subjects. However, this promise is thwarted by our inadequate understanding of the linkage between neural activity and fMRI signals, and by inherent limitations of current fMRI methods. We will investigate the neural basis of fMRI signals through experiments that combine high field fMRI with neural ensemble electrophysiology and pharmacology in monkeys; fMRI will be conducted with BOLD- and perfusion-sensitive protocols using a high-resolution, high signal-to-noise 7-Tesla system. Electrophysiology will utilize both scalp ERP recordings, and depth recordings with linear array multielectrodes, and will focus on ERP and current source density (CSD) measures as well as action potentials. CSD measures in particular, are essential for linking neural activity and fMRI. Neurochemical manipulation will entail both systemic infusions and intracortical microinfusions. Our specific aims are: 1. To Identify Neural Correlates of BOLD-fMRI: 2. To Optimize the Spatial and Temporal Resolution of fMRI 3. To Determine the Relationship of fMRI to ERPs and to Brain Processes. Initial studies will be conducted in anesthetized macaque monkeys & will focus on the cortical hand representation in Area 3b. Later studies will be implemented in awake monkeys & will be expanded to a few additional cortical regions. These studies will have the useful by-product of accurately describing the spatiotemporal activation pattern of the ascending somatosensory pathways from the hand surface in the macaque, and of doing so with methods that directly compare to those used in humans. This will help to bridge-the-gap between a vast single unit literature in monkeys, and a developing understanding of somatosensory structure and function in humans.

描述（由申请人提供）：功能磁共振成像（fMRI）有望在其完整受试者的正常操作过程中提供能力和跟踪脑活动模式，运动，运动和认知技能的基础。但是，由于我们对神经活动与fMRI信号之间的联系以及当前fMRI方法的固有局限性的理解不足，这一诺言受到了挫败。我们将通过将高场fMRI与猴子中的神经集合电生理学和药理学相结合的实验来研究fMRI信号的神经基础。 FMRI将使用高分辨率高分子到噪声7-Tesla系统使用大胆和灌注敏感的方案进行。电生理学将同时利用头皮ERP记录和线性阵列多电极的深度记录，并将专注于ERP和电流源密度（CSD）测量以及动作电位。尤其是CSD度量，对于连接神经活动和fMRI至关重要。神经化学操作将需要全身输注和心脏内微觉。我们的具体目的是： 1。确定Bold-FMRI的神经相关性： 2。优化fMRI的空间和时间分辨率 3。确定fMRI与ERP和大脑过程的关系。 初步研究将在麻醉的猕猴中进行，并将集中于3B区域的皮质手动代表。后来的研究将在清醒猴子中实施，并将扩展到其他一些皮质区域。这些研究将具有有用的副产品，即准确地描述了从猕猴中的手表面上升的体感途径的时空激活模式，并使用与人类使用的方法直接进行的方法。这将有助于弥合猴子庞大的单元文献之间的差距，以及对人类体感结构和功能的发展理解。