Characterization of neurovascular and neurometabolic coupling of the negative BOLD response in human

人类负性 BOLD 反应的神经血管和神经代谢耦合特征

• 批准号: 10819782
• 负责人: JungHwan Kim
• 金额: $ 42.02万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-01 至 2026-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10819782
• 关键词: Blood flow; Brain; Brain Pathology; Brain region; Cerebrovascular Circulation; Characteristics; Computer Models; Core-Binding Factor; Coupling; Data; Failure; Functional Magnetic Resonance Imaging; Goals; Human; Image; Ipsilateral; Knowledge; Measurement; Measures; Metabolism; Methods; Modality; Modeling; Neurons; Neurosciences; Oxygen; Physiological; Physiology; Reporting; Research; Resolution; Sampling; Scheme; Signal Transduction; Somatosensory Cortex; Stimulus; Structure; Surface; Synapses; Time; Variant; Venous; Visual Cortex; arterial spin labeling; blood oxygen level dependent; brain dysfunction; deoxyhemoglobin; experimental study; gray matter; hemodynamics; imaging study; indexing; neural; neurovascular; novel; response; spatiotemporal; success; temporal measurement; trend; vasoconstriction

Project Summary For task-based functional magnetic resonance imaging (fMRI), the positive blood-oxygen-level-dependent (BOLD) response has been widely used and often assumed that it linearly reflects local neural activity. However, a significant portion of brain regions responds with signal decreases upon activation, known as the negative BOLD response (NBR). Although the negative BOLD response (NBR) and its origin have been explored extensively, temporal characteristics and spatial structure of the NBR, and corresponding underlying physiological dynamics are still poorly understood. We propose to investigate dynamics of the NBR evoked by a brief stimulus –the negative hemodynamic response function (nHRF) and its underlying neurovascular and neurometabolic responses using our novel experimental paradigms with high spatiotemporal resolution BOLD and arterial spin labelling (ASL) fMRI modalities. High spatial and temporal resolution BOLD measurements will resolve temporal dynamics of the nHRF as a functional of cortical depth and distance from adjacent positive BOLD responses along the cortical surface. We also evaluated shift-invariant temporal linearity by measuring dynamics of the NBR for varying stimulus durations. Fine spatiotemporal sampling ASL measurements in conjunction with a novel stimulus- onset-time dithering scheme will provide accurate quantification of the cerebral blood flow associated with the NBR within gray matter. We advance our novel computational model based on prompt arterial dynamics observed in recent experimental studies, enabling estimation of realistic neurometabolic response associated with the nHRF. The model will offer a better detailed interpretation of the underlying physiological components associated with the nHRF. Our proposed research will provide a detailed understanding of neurovascular and neurometabolic (de-)coupling associated with nHRF, expanding our knowledge of normal brain functions. Such details with precision to understand the NBR and its physiology was not available in previous studies. Ultimately, success of our proposed research will motivate use of the proposed fMRI approaches and modeling schemes for brain pathologies that involve neurovascular and neurometabolic coupling.

项目摘要 对于基于任务的功能磁共振成像（fMRI），阳性血氧级依赖性 （BOLD）反应已被广泛使用，并且经常假定其线性反映局部神经活动。 然而，大脑区域的很大一部分在激活后信号下降，称为信号下降，称为 负大胆响应（NBR）。尽管负面响应（NBR）及其起源 广泛探索了NBR的临时特征和空间结构，并相应的基础 生理动力学仍然知之甚少。 我们建议研究通过短暂刺激引起的NBR的动力学 - 阴性血流动力学 使用我们的小说 具有高时空分辨率的实验范例粗体和动脉自旋标记（ASL）fMRI 方式。高空间和临时分辨率大胆测量将解决该临时动力学 NHRF作为皮质深度和距离皮质相邻阳性粗体反应的距离的功能 表面。我们还通过测量NBR的动力学来评估偏移不变的临时线性性 刺激持续时间。精细的空间时间采样ASL测量与新型刺激 - 发作时间分化方案将提供与与 灰质内的nbr。我们基于迅速动脉动力学推进了新颖的计算模型 在最近的实验研究中观察到，可以估计与现实的神经代谢反应相关的估计 与NHRF。该模型将对基本生理组件的更好详细解释 与NHRF相关。 我们提出的研究将提供对神经血管和神经代谢的详细理解 （DE-）与NHRF相关的耦合，扩大了我们对正常脑功能的了解。此类细节 在先前的研究中，无法理解NBR及其生理学的精度。最终，成功 我们提出的研究将激励使用拟议的fMRI方法和为大脑建模方案 涉及神经血管和神经代谢耦合的病理。