Biological Spatial Resolution Limits in fMRI

fMRI 中的生物空间分辨率限制

• 批准号: 8044958
• 负责人: Jonathan Rizzo Polimeni
• 金额: $ 17.54万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-15 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8044958
• 关键词: Amblyopia; Anatomy; Animals; Architecture; Area; Biological; Biology; Blood; Blood Vessels; Blood capillaries; Blood flow; Brain; Cerebral Amyloid Angiopathy; Computer Analysis; Core-Binding Factor; Cortical Column; Coupling; Data; Data Analyses; Distal; Electrical Engineering; Exhibits; Experimental Designs; Faculty; Functional Magnetic Resonance Imaging; Future; General Hospitals; Goals; Histology; Human; Hyperemia; Image; Imaging Techniques; Individual; Joints; Knowledge; Macaca; Magnetic Resonance Imaging; Maps; Massachusetts; Measurement; Measures; Mentorship; Methodology; Methods; Metric; Modeling; Monkeys; Nervous system structure; Neurons; Ocular Dominance; Ocular dominance columns; Output; Patients; Pattern; Physics; Physiology; Pial Veins; Positioning Attribute; Prosthesis; Protocols documentation; Radial; Relative (related person); Resolution; Rest; Sampling; Signal Transduction; Slice; Specificity; Stimulus; Structure; Surface; Techniques; Testing; Tissues; Training; Training Support; Vascular System; Veins; Visual; Visual Cortex; Visual system structure; area V1; area striata; base; bioimaging; capillary; career development; computational neuroscience; data acquisition; density; design; design and construction; detector; hemodynamics; imaging modality; improved; insight; instrumentation; member; monocular; neuroimaging; new technology; novel; optical imaging; orientation selectivity; radiofrequency; relating to nervous system; response; retinotopic; tool; white matter

DESCRIPTION (provided by applicant): This project will support the training and career development of a junior faculty member, with prior training in computational neuroscience and electrical engineering, transitioning into the fields of magnetic resonance imaging (MRI) and functional neuroimaging. This training will take place at the A. A. Martinos Center for Biomedical Imaging at the Massachusetts General Hospital, under the mentorship of Prof. L. L. Wald, within the Ultrahigh-field Imaging and Imaging Physics Group. The candidate will conduct a study into quantifying the fundamental biological limits of spatial resolution in functional MRI, and perform precise measurements of the functional architecture of the human visual system using novel methods developed to overcome resolution limits placed by the instrumentation, data acquisition and experimental design, and data analysis. The long-term objective of this project is to enable non-invasive imaging of fine-scale details of the human visual cortex, including the distinctive spatial maps of orientation preference, ocular dominance, and retinotopy, with a spatial resolution sufficient to derive accurate, quantitative measurements of these basic features of the visual system. To quantify the biological limits of spatial resolution, this study will focus on three aims: (i) to develop a methodology for quantifying spatial resolution and accuracy in fMRI; (ii) to measure spatial accuracy across multiple experimental designs and identify which provides the highest achievable resolution; and (iii) to exploit this knowledge to measure and quantify the topographic and columnar structures in primary visual cortex, and thus draw informed conclusions about their organization based on the known measurement accuracy. Although estimates of spatial resolution have been made in the past, new advances in both acquisition and analysis technology, and new insights into experimental design, require that these estimates be re-assessed to determine what is now feasible. Importantly, emerging methods at our disposals enable resolving activity within individual cortical laminae. Not only does laminar fMRI open possibilities for testing new hypotheses about the nervous system and neurovascular coupling, but the proposed methods may yield a practical technique for increasing spatial resolution-due to the tighter biological point-spread expected in central vascular layers distal to large pial veins, targeted sampling of these layers will enable higher achievable spatial resolution. The candidate will receive training in ultrahigh-field imaging methods, accelerated parallel imaging techniques, design and construction of radiofrequency coil detectors, accurate computational analysis of fMRI data, and the anatomy and physiology of the human brain and its vascular system. The tools developed for this study can assist in several applications such as identifying pathological tissue in patients with visual deficits or amblyopia, measuring the impact of localized hyperemia in patients with occipital cerebral amyloid angiopathy, designing cortical prostheses, and will enable future studies into the fine organization of the nervous system. PUBLIC HEALTH RELEVANCE: PROJECT NARRATIVE The spatial accuracy of functional MRI is limited by the biology of blood delivery. We will impose spatial patterns of activity along the cortex to measure the spatial accuracy in individual cortical layers, and use these patterns to test methods for further improving accuracy.

描述（由申请人提供）：该项目将支持初级教职员工的培训和职业发展，并在计算神经科学和电气工程领域进行了先前的培训，过渡到磁共振成像（MRI）和功能性神经成像领域。这项培训将在Massachusetts综合医院的A. A. Martinos生物医学成像中心举行，在L. L. Wald教授的指导下，在Ultrahigh-Field Imaging和Imaging Physics Group中。候选人将进行一项研究，以量化功能性MRI空间分辨率的基本生物学限制，并使用开发的新方法对人类视觉系统的功能架构进行精确测量，以克服仪器，数据采集，实验设计和数据分析的分辨率限制。该项目的长期目的是实现人类视觉皮层细节的细节的非侵入性成像，包括独特的空间图，偏好，眼优势和视网膜的独特空间图，并具有足以衍生出这些视觉系统这些基本特征的精确定量测量的空间分辨率。 为了量化空间分辨率的生物学极限，本研究将重点介绍三个目的：（i）开发一种量化fMRI中空间分辨率和准确性的方法； （ii）测量多个实验设计的空间精度并确定提供最高可实现的分辨率的空间精度； （iii）利用这些知识来衡量和量化主要视觉皮层中的地形和柱状结构，因此根据已知的测量准确性得出有关其组织的明智结论。尽管过去已经对空间分辨率进行了估计，但是采集和分析技术的新进步以及对实验设计的新见解，要求对这些估计值进行重新评估，以确定现在可行的内容。重要的是，在我们的处置中的新兴方法可以在单个皮质层层中进行解决活动。层流FMRI不仅开放了有关神经系统和神经血管耦合的新假设的开放可能性，而且提出的方法可能会产生一种实用的技术，可将空间分辨率提高到更严格的生物学点范围，以使其在中央血管中预期的更紧密的生物学点范围在大型的pial静脉中远端的较高的型脉管，而较高的spatiep spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat spat。 候选人将接受超高场成像方法的培训，加速的并行成像技术，射频线圈探测器的设计和构建，fMRI数据的准确计算分析以及人类大脑及其血管系统的解剖学和生理学。为这项研究开发的工具可以帮助一些应用，例如鉴定视觉缺陷或弱视患者的病理组织，测量局部充血对枕脑淀粉样血管病患者的影响，设计皮质假体，并将使未来的研究成为神经系统的良好组织。 公共卫生相关性：项目叙事功能MRI的空间准确性受血液输送的生物学限制。我们将沿皮层施加空间活动的空间模式，以测量单个皮质层中的空间精度，并使用这些模式测试方法以进一步提高准确性。