Cerebral Blood Flow and BOLD Changes in TBI using fMRI

描述（由申请人提供）：fMRI作为了解TBI（创伤性脑损伤）对人类认知和运动功能影响的工具，其巨大潜力已经开始被认识到，因为大量的神经认知TBI文献已经开始出现（McAllister et al., 1999; 2001; Christodoulou et al., 2001）。虽然这些发现的一致性令人鼓舞，但关于脑损伤对fMRI测量的大脑激活模式的影响的结论的有效性将取决于更好地描述观察到的大脑激活模式的广泛变化（Hillary, Steffener， Biswal等人，2002）。我们的建议的目的是系统地检查和量化血管和神经因素有助于创伤相关的变化在功能磁共振成像信号。据我们所知，这是第一次尝试全面检查生物物理、神经和认知对tbi相关的fMRI激活差异的贡献。我们在这里提出的开发和利用的技术可以被其他研究人员实施，以准确地分离由于创伤相关（或者，实际上，任何与人群相关的）神经活动差异而引起的血流动力学变化。正因为如此，目前的提案提供了建立将BOLD fMRI应用于临床样本的新标准的机会。本项目旨在结合基础科学、工程和计算问题，具体阐明导致创伤性脑损伤受试者与健康对照组相比大脑激活改变的机制（神经元vs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对其进行生物物理表征的方法，以了解脑外伤患者的大脑功能。所开发的方法和技术也可用于两个或更多不同群体之间的研究。

DESCRIPTION (provided by applicant): The enormous potential of fMRI as a tool for understanding the influences of TBI (Traumatic Brain Injury) on cognitive and motor functioning in humans has begun to be realized as a body of neurocognitive TBI literature has started to emerge (McAllister et al., 1999; 2001, Christodoulou et al., 2001). While the consistency in these findings has been encouraging, the validity of conclusions regarding the influences of TBI on brain activation patterns measured by fMRI will be dependent upon better characterizing the wide variability in brain activation patterns observed (Hillary, Steffener, Biswal et al., 2002). The aim of our proposal is to systematically examine and quantify the vascular and neural factors contributing to trauma- related changes in the fMRI signal. To the best of our knowledge, this is the first attempt to comprehensively examine the biophysical, neural, and cognitive contributions to TBI-related differences in fMRI activation. The techniques we propose to develop and utilize here can be implemented by other investigators to accurately isolate hemodynamic changes due to trauma-related (or, indeed, any population-related) differences in neural activity. Because of this, the current proposal provides the opportunity to establish new standards for applying BOLD fMRI to clinical samples.. The present project intends to combine basic science, engineering, and computational issues to specifically elucidate mechanisms (neuronal vs vascular) that results in TBI subjects having altered brain activation in comparison to healthy controls. 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 TBI. Methods and techniques developed can also be used to study between two or more different groups.