Functional MRI of Aging: Biophysical Characterization

衰老的功能 MRI：生物物理特征

• 批准号: 8494485
• 负责人: Bharat Bhusan Biswal
• 金额: $ 27.96万
• 依托单位: NEW JERSEY INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8494485
• 关键词: Accounting; Address; Adult; Affect; Age; Age-Years; Aging; Area; Basic Science; Biological Markers; Blood Vessels; Blood Volume; Blood flow; Brain; Brain region; Cerebrovascular Circulation; Cerebrum; Cognitive; Data; Elderly; Engineering; Erythrocytes; Evolution; Functional Magnetic Resonance Imaging; Human; Human Volunteers; Hypercapnia; Individual; Lead; Light; Longevity; Longitudinal Studies; Magnetic Resonance Imaging; Maps; Measurement; Measures; Mediating; Methods; Modeling; Nature; Neurocognitive; Neurons; Oxyhemoglobin; Pattern; Performance; Physiological; Population; Positron-Emission Tomography; Predisposition; Property; Relative (related person); Reporting; Short-Term Memory; Signal Transduction; Site; Source; Staging; Task Performances; Techniques; Technology; Testing; Time; Variant; Vasodilation; Vasomotor; age related; base; blood oxygen level dependent; cerebrovascular; density; deoxyhemoglobin; design; digital; hemodynamics; insight; neuroimaging; neuron loss; normal aging; public health relevance; relating to nervous system; response; senescence; tissue oxygenation; young adult

DESCRIPTION (provided by applicant): In the recent years, a number of studies using functional MRI (fMRI) have shown substantial differences between the activation pattern of older subjects (> 50 years of age) and younger subjects (21-40 years) while performing a number of different sensorimotor and cognitive tasks. It has been concluded that the contrast observed is due to differences in neuronal activity in the older subjects. However, early hypothesis that normal aging involves widespread loss of neurons have been revised in light of accumulating evidence that in most regions of the brain, the number of neurons is stable throughout adulthood and senescence. In addition to direct effects on neuronal function, factors contributing to cerebrovascular reactivity is known to be altered in older people that could give rise to altered hemodynamic responses. Since the signal observed using fMRI could be modulated both by hemodynamics and oxygenation changes resulting from neuronal changes, these two factors must be separated to gain a better understanding about age related changes in the activation pattern obtained using fMRI. The present project proposed intends to combine basic science, engineering, and computational issues to specifically elucidate mechanisms (neuronal vs vascular) that results in older subjects having altered brain activation in comparison to young subjects. Results obtained from the noninvasive technique (fMRI) would provide ways to measure a number of relevant physiological factors and characterize them biophysically to understand human brain function with aging. Methods and techniques developed can also be used to study between two or more different groups. PUBLIC HEALTH RELEVANCE: The present project will help determine biophysical aspects of aging using non-invasive functional Magnetic Resonance Imaging (fMRI). As longitudinal studies are very important to follow individuals through different stages of their life span, fMRI techniques would become crucial in obtaining valuable biomarkers in studies of aging. FMRI presents many caveats in determining the actual physiological indicators that influence signal response in young and old subjects. This project is designed to address certain caveats by effectively testing and quantifying the neural and hemodynamic components that may modulate signal response in young and old subjects. This study will significantly gain information regarding the underlying nature and necessary corrections in fMRI signals. Such a correction is necessary to accurately determine the progression and determinants of change across all segments of the life span that affect cognitive effects and brain function.

描述（由申请人提供）：近年来，使用功能性MRI（fMRI）的许多研究表明，老年受试者（> 50岁）的激活模式与年轻受试者（21-40岁）之间存在很大差异，同时执行许多不同的感觉运动和认知任务。已经得出结论，观察到的对比是由于较老受试者的神经元活性差异所致。然而，鉴于累积的证据表明，在整个成年和衰老的大脑中，正常衰老的早期假设已经涉及神经元广泛丧失的神经元丧失。除了直接对神经元功能的影响外，已知有助于脑血管反应性的因素在老年人中会改变，这可能会导致血液动力学反应改变。由于使用fMRI观察到的信号可以通过血液动力学和神经元变化导致的氧合变化来调节，因此必须分开这两个因素，以更好地了解使用FMRI获得的激活模式中与年龄相关的变化。本项目提出了将基础科学，工程和计算问题相结合，以特别阐明机制（神经元与血管），从而导致与年轻受试者相比，较旧的受试者大脑的激活改变了。从非侵入性技术（fMRI）获得的结果将提供方法来测量许多相关的生理因素并以生物物理为特征，以了解衰老的人脑功能。开发的方法和技术也可用于研究两个或更多不同的组之间。 公共卫生相关性： 本项目将有助于使用非侵入性功能磁共振成像（fMRI）确定衰老的生物物理方面。由于纵向研究对于遵循个人的寿命不同阶段非常重要，因此fMRI技术对于在衰老研究中获得有价值的生物标志物至关重要。 fMRI在确定影响年轻和老年受试者信号反应的实际生理指标时提出了许多警告。该项目旨在通过有效测试和量化可能调节老年和老年受试者信号反应的神经和血液动力学成分来解决某些警告。这项研究将显着获得有关fMRI信号中基本性质和必要校正的信息。这样的校正对于准确确定影响认知效果和大脑功能的所有段的变化的进展和决定因素是必要的。