Functional MRI of Aging: Biophysical Characterization

衰老的功能 MRI：生物物理特征

• 批准号: 7785668
• 负责人: Bharat Bhusan Biswal
• 金额: $ 31.59万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 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 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7785668
• 关键词: Accounting; Address; Adult; Affect; Age; Age-Years; Aging; Area; Barbus; 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; Yang; 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，许多使用功能性磁共振成像（fMRI）的研究表明，老年受试者（> 50岁）和年轻受试者（21-40岁）在执行许多不同的感觉运动和认知任务时，激活模式之间存在显着差异。结论是观察到的对比是由于老年受试者神经元活动的差异造成的。然而，随着越来越多的证据表明，在大脑的大多数区域，神经元的数量在整个成年期和衰老过程中保持稳定，人们对正常衰老涉及神经元广泛丧失的早期假设进行了修正。除了对神经元功能的直接影响外，已知老年人脑血管反应性的影响因素也会发生改变，从而导致血流动力学反应改变。由于使用 fMRI 观察到的信号可以通过神经元变化引起的血流动力学和氧合变化来调节，因此必须将这两个因素分开，以便更好地了解使用 fMRI 获得的激活模式中与年龄相关的变化。目前提出的项目旨在结合基础科学、工程和计算问题，专门阐明导致老年受试者与年轻受试者相比大脑激活发生改变的机制（神经元与血管）。从无创技术（fMRI）获得的结果将提供测量许多相关生理因素并从生物物理角度表征它们的方法，以了解人类大脑随衰老的功能。开发的方法和技术也可用于两个或多个不同群体之间的研究。 公共卫生相关性： 本项目将利用非侵入性功能磁共振成像（fMRI）帮助确定衰老的生物物理方面。由于纵向研究对于跟踪个体生命周期的不同阶段非常重要，因此功能磁共振成像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注意事项。该项目旨在通过有效测试和量化可能调节年轻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问题。这项研究将显着获得有关功能磁共振成像信号的基本性质和必要校正的信息。这种校正对于准确确定影响认知效果和大脑功能的生命周期所有阶段的变化的进展和决定因素是必要的。