Ultra-high resolution BOLD fMRI of medial temporal lobe at 7 Tesla

7 特斯拉下内侧颞叶超高分辨率 BOLD fMRI

• 批准号: 8638540
• 负责人: Sandhitsu Das
• 金额: $ 8万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8638540
• 关键词: Address; Affect; Aging; Alzheimer' s Disease; Area; Attention; Autopsy; Biological Markers; Biological Neural Networks; Brain; Brain region; Characteristics; Clinical; Clinical Investigator; Cognitive; Communities; Complex; Data; Data Set; Development; Disease; Dissociation; Eating; Echo-Planar Imaging; Episodic memory; Experimental Designs; Functional Imaging; Functional Magnetic Resonance Imaging; Functional disorder; Funding; Future; Goals; Gold; Hippocampal Formation; Hippocampus (Brain); Histologic; Human; Image; Imaging Techniques; Imaging technology; Individual; Investigation; Label; Learning; Magnetic Resonance Imaging; Measures; Medial; Memory; Methodology; Methods; Metric; Motivation; Nerve Degeneration; Neuroanatomy; Neurocognitive; Noise; Pathology; Pattern; Physiologic pulse; Physiological; Pilot Projects; Play; Population; Procedures; Process; Property; Research; Resolution; Rodent; Role; Signal Transduction; Specific qualifier value; Specificity; Staining method; Stains; Structure; System; Techniques; Technology; Temporal Lobe; Testing; Time; Tissue Sample; Weight; Work; age group; animal data; base; cohort; dentate gyrus; design; entorhinal cortex; human data; improved; in vivo; magnetic field; memory process; nervous system disorder; network architecture; neuroimaging; non-invasive imaging; open source; public health relevance; research study; software development; ultra high resolution

DESCRIPTION (provided by applicant): The medial temporal lobe (MTL) is an important brain region that subserves functions of episodic memory and learning. MTL contains the hippocampal formation, composed of histologically and functionally distinct sub- fields, and extra-hippocampal cortices. Subfield-specific memory functions have so far been investigated using high-resolution MRI at 3 Tesla. However, 7 Tesla MR scanners are capable of acquiring ultra-high resolution MR images that can potentially resolve functional activation at an even finer level within smaller subfields such as CA2 and CA3, and at the same time provide structural images with superior contrast properties for localiz- ing subfields. However, smaller voxels and greater magnetic field inhomogeneity pose challenges to acquiring functional MRI data with acceptable image quality at higher field strengths, particularly in the MTL. In this pilot project,we propose to develop and optimize MR acquisition sequences to obtain ultra-high resolution BOLD fMRI at a resolution of 1x1x1 mm3. We will implement state-of-the-art distortion-correction and SNR improve- ment techniques using a combination of image acquisition and post-processing methods to satisfy pre- specified signal-quality metrics in the MTL. We will then demonstrate the utility of ultra-high resolution fMRI in an experiment designed to dissoci- ate BOLD fMRI activation in CA3 and DG subfields. Subfields will be labeled in 7T structural MRI using ground truth histological labeling as reference. The experimental paradigm will operationalize pattern separation and pattern completion-based memory processes which have been shown to differentially activate CA3 and DG subfields under certain conditions in rodents, but similar effects have not been shown in humans. If successful, this project will enable testing of complex, MTL subregion-specific hypotheses regarding human episodic memory function in healthy brain. Additionally, it can provide a granular understanding of ef- fects of pathology on the episodic memory system, as involvement of MTL subregions often show a topo- graphic specificity in many neurological disorders, including Alzheimer's Disease. Finally, this work will provide a comprehensive image acquisition and analysis framework for future imaging-based investigations to more finely characterize normative function as well as the effects of pathology on MTL-supported cognitive proc- esses.

描述（申请人提供）：内侧颞叶（MTL）是一个重要的大脑区域，支持情景记忆和学习功能。MTL包含海马结构，由组织学和功能上不同的亚区和海马体外皮层组成。子场特定的记忆功能迄今为止已经使用3特斯拉的高分辨率MRI进行了研究。然而，7台特斯拉磁共振扫描仪能够获得超高分辨率的磁共振图像，可以更精细地解析功能激活