High Fidelity fMRI

高保真功能磁共振成像

• 批准号: 7027733
• 负责人: ALLEN W SONG
• 金额: $ 27.82万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-15 至 2008-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7027733
• 关键词: adult human (21+); bioimaging /biomedical imaging; brain circulation; brain electrical activity; capillary; central neural pathway /tract; clinical research; data collection methodology /evaluation; evoked potentials; face expression; functional magnetic resonance imaging; human subject; image processing; magnetic field; magnetic resonance imaging; method development; neural information processing; neuroanatomy; neurons; visual perception

DESCRIPTION (provided by applicant): The main objective of this proposal is to improve the fidelity of fMRI localization to sites of neuronal activities. Two pre-requisites for achieving such an objective are uniform spatial coverage of relevant brain structures and accurate spatial localization of specific functional regions. Thus, we will develop improved acquisition methods that can ensure uniform spatial coverage in the presence of aggravated susceptibility artifacts at brain regions near air/tissue/bone interface and at high magnetic fields (e.g. 4T). We will also develop improved acquisition methods using dynamic apparent diffusion coefficient (ADC) contrast to achieve accurate spatial localization of the functional signal to the capillary networks that are closely tied to the neuronal activities. To this end, we propose three specific aims: First, improved acquisition methodology at high magnetic fields for uniform coverage and minimal distortion without the spatial confound of susceptibility artifacts will be developed and validated. Such method is especially needed at ventral brain regions where static susceptibility effects are pronounced. Second, improved acquisition methods with high temporal and spatial resolution will be developed to singularly detect synchronized ADC changes in capillary networks for close spatial coupling to the neuronal activities. Such signal changes will be compared with those obtained from the traditional blood oxygenation level dependent (BOLD) and cerebral blood flow (CBF) weighted contrasts to assess the improved spatial localization, using controlled visual activation paradigms. Third, using activated regions from the invasive intra-cranial electrical grid recordings during face and object recognition tasks as a standard, further validation of the localization ability of the susceptibility-compensated dynamic ADC contrast (optimized in the first two aims) in the ventral and middle temporal brain areas will be carried out using the same activation tasks. In parallel, the activated brain regions will also be used as seed points to initiate a diffusion tensor imaging (DTI) based nerve fiber tracking process to non-invasively validate their neuronal origins, based upon the knowledge that areas closely tied to the functioning neuronal populations are well connected by neural pathways. Together these three specific aims will help achieve the ultimate goal of neuroimaging for reliable, accurate and efficient localization of the neuronal activities, creating a comprehensive platform for assessing brain anatomy, function and neural pathways. It is anticipated that successful completion of the current research project will greatly improve the spatial specificity of the functional localization, effectively bridging the gap between neuroanatomy and neuroimaging.

描述（由申请人提供）： 该提案的主要目的是提高fMRI定位对神经元活动部位的保真度。实现这一目标的两个先决条件是对相关大脑结构的统一空间覆盖和特定功能区域的准确空间定位。因此，我们将开发改进的采集方法，以确保在空气/组织/骨界面和高磁场（例如4T）附近的大脑区域的严重敏感性伪影（例如4T）的情况下确保均匀的空间覆盖。我们还将使用动态明显扩散系数（ADC）对比度进行改进的采集方法，以实现与神经元活动紧密相关的毛细管网络的功能信号的准确空间定位。为此，我们提出了三个特定的目标：首先，将开发和验证均匀覆盖范围的高磁场的采集方法，用于均匀覆盖和最小的失真，而没有空间混淆。在静态易感性效果的腹侧大脑区域中，这种方法尤其需要。其次，将开发具有高时间和空间分辨率的改进的采集方法，以奇异地检测毛细血管网络中的同步ADC变化，以与神经元活性密切相关。这种信号变化将与从传统的血液氧合水平（BOLD）和脑血流量（CBF）加权对比度获得的变化进行比较，以评估改善的空间定位，并使用受控的视觉激活范例进行了评估。第三，将来自侵入性的颅内电网记录中的活性区域和对象识别任务作为标准，进一步验证腹侧和中部术语中术中易感性补偿性的动态ADC对比度（在前两个目标中进行了优化），将使用同一激活任务来携带。同时，激活的大脑区域还将用作种子点，以启动基于扩散的张量成像（DTI）的神经纤维跟踪过程，以非侵入性地验证其神经元的起源，因为它的知识是，与功能性神经元群体相关的区域通过神经途径良好连接。这三个特定的目标将有助于实现神经影像学的最终目标，以对神经元活动的可靠，准确和有效的定位，从而创建一个全面的平台来评估大脑解剖学，功能和神经途径。可以预计，当前研究项目的成功完成将大大改善功能定位的空间特异性，从而有效地弥合了神经解剖学和神经影像学之间的差距。