Brain Activation in Humans

描述(由申请人提供)： 越来越需要证据来支持康复的临床决策。神经成像方面的进展对于支持和完善康复干预措施至关重要。近红外光谱(NIRS)是一种新兴的神经功能成像技术，相对于功能磁共振成像(FMRI)具有便携的优点。NIRS有可能成为一种有效的神经康复结果衡量标准。它是一种光学神经成像手段，可间接监测皮质血红蛋白的局部波动。 氧合作用，随着神经活动的变化而变化。它是便携的，非侵入性的，允许在自然环境中相对自由地移动。因此，如果NIRS被确定为可靠和有效的，那么它可能是追踪神经恢复和探索神经可塑性的有用工具。先前检验NIRS可靠性的研究报告称，在各种人群和大脑皮层区域，NIRS与功能磁共振成像之间存在中到强的相关性(ICC=0.5-0.83)。近红外光谱效度研究 都显示出同样强劲的结果。这些研究使用了基于任务或刺激的范式，如手部运动、言语产生或对视觉刺激的被动观察。人类神经成像中最有前途的范例之一是研究fMRI血氧水平依赖(BOLD)信号的缓慢(&lt；0.1赫兹)波动。在没有外显任务的情况下，神经系统之间存在着很强的时间相关性。这种自发活动(即休息状态)指的是不属于特定输入或输出的活动；它代表由大脑内在产生的活动。由于没有任务，研究可以在不愿意或不能坚持任务范式的人中进行，并可能绕过对任务表现、镜像运动、头部运动或任务策略差异的担忧。在健康个体中，静息状态的fMRI数据已经被证明是非常一致的，这意味着网络分析在后续的纵向治疗相关操作中将是有用的。使用近红外光谱检查了静息状态功能连接图的重复性。支持其实用性的证据基于有限的样本量(n=5)。我们的研究将使用结构方程模型(SEM)来评估中风患者视觉和运动网络有效连接的可靠性和重复性。我们将检验以下假设：1)在一次7分钟的治疗过程中，以及在相隔7天的两次治疗之间，fNIRS时间历程在中风患者和健全对照组中将是可靠的；2)在中风患者超过12个月的患者和健康对照组中，fNIRS有效连接图和fMRI有效连接图之间将存在显著的关联。预期的研究结果将证实，可以在中风患者中可靠地获得静息状态的NIRS连接图；因此，除了可以评估竞争疗法的行为结果外，未来还可以应用静息状态的NIRS来提供成像指标。

DESCRIPTION (provided by applicant): There is a growing need for evidence to support clinical decision making in rehabilitation. Advancements in neuroimaging are essential for the support and refinement of rehabilitative interventions. Near-infrared spectroscopy (NIRS) is an emerging functional neuroimaging technique with advantages, relative to functional magnetic resonance imaging (fMRI) of portability. NIRS has the potential to be an effective neurorehabilitation outcome measure. It is an optical neuroimaging modality that indirectly monitors local fluctuations in cortical hemoglobin oxygenation, which change with neural activity. It is portable, non-invasive and allows for comparatively free movement within a natural environment. Therefore, NIRS may be a useful instrument to track neural recovery and explore neural plasticity if determined to be reliable and valid. Previous studies examining the reliability of NIRS report moderate to strong correlations (ICC = 0.5- 0.83) with fMRI in a variety of populations and cortical regions. NIRS validity studies have demonstrated equally robust results. These studies used task or stimulus-based paradigms such as hand movements, speech production or passive observation of visual stimulus. One of the most promising paradigms in human neuroimaging is the study of slow (< 0.1 Hz) fluctuations in the fMRI blood-oxygen level dependent (BOLD) signal. Strong temporal correlations among neural systems exist in the absence of an overt task. This spontaneous activity (i.e. resting state) refers to activity that is not attributable to specific inputs or oututs; it represents activity that is intrinsically generated by the brain. As there is no task, studies can e conducted in people unwilling or unable to adhere to task paradigms and may circumvent concerns about differences in task performance, mirror movement, head motion, or task strategy. Resting-state fMRI data has been shown to be remarkably consistent across session in healthy individuals, implying that network analysis would be useful in following longitudinal treatment-related manipulations. Repeatability of resting state functional connectivity maps have been examined using NIRS. Evidence to support their utility have been based upon a limited sample size (n=5). Our study will use structural equation modeling (SEM) to evaluate the reliability and repeatability in effective connectivity of the visual and motor networks in patient with stroke. We will test the hypotheses that 1) fNIRS timecourses will be reliable in people with stroke and able-bodied controls within one seven-minute session and between two sessions conducted 7 days apart, and 2) there will be significant association between the fNIRS effective connectivity maps and the fMRI effective connectivity maps in people who suffered stroke greater than 12 months and in able-bodied controls The expected findings will confirm that resting-state NIRS connectivity maps can be reliably obtained in people with stroke; thus permitting future application of resting state NIRS to provide imaging metrics, in addition to behavioral outcomes, by which competing therapies may be evaluated.