Characterizing Large-scale Neuroplastic Changes in Cerebral Compared to Ocular Visual Impairment

摘要 这项拟议研究的目的是更好地了解精神分裂症的潜在神经生理学。 大脑/皮质视力障碍(CVI)是美国先天性视力丧失的主要原因， 发达国家。CVI与围产期视觉大脑结构和通路的损害有关，以及 会导致大量的视觉功能损伤。尽管存在这一令人担忧的公共卫生问题，但 我们对视觉系统在大脑环境中是如何发展的理解上的根本差距 与以眼睛为基础的视力损害相比。目前使用标准临床成像模式的研究有 限制了他们在广泛的神经学背景下表征大脑功能重组的能力 受伤。为了进一步加深我们的理解，我们将使用多模式神经成像来表征整个 脑室周围CVI患者的脑以及局部结构和功能脑连通性 白质软化症(PVL)。在我们的第一个目标中，我们将使用以下方法表征白质完整性和结构连接性 高角分辨率扩散成像(HARDI)。在我们的第二个目标中，我们将描述大脑的功能 使用静息状态功能连接(Rsfc)MRI的连接网络。使用图论分析 框架，然后我们将研究网络的拓扑属性以及结构和 功能网络。功能连通性的进一步表征将使用逐步进行 功能连接性(SFC)分析。这种互补的方法允许调查 在整个大脑中信息传输的广泛网络改变，代表着一个关键 这一建议的独特创新之处在于。具体地说，拓扑特征的检查和 结构-功能网络耦合的本质将通过揭示 先天性脑损伤环境中网络改变的性质及其与视觉功能的关系。 研究结果将与眼部视觉受损(OVI)患者(与残存视功能匹配)进行比较，如下所示 以及典型的视力正常的对照组。我们的主要假设是，CVI与关键差异有关 在结构-功能连接网络之间的组织和关系中。此外，我们 预测在CVI中，负责视觉处理的功能网络将显示出重组的证据 对大规模白质损伤的反应，这可能是一个与临床相关的有用的生物标志物 功能评估。这项研究将提供以前从未达到的高度洞察力 以前的研究依赖于标准的临床成像方法。揭示大脑是如何发育的 CVI的情况以及它与基于眼睛的视觉损害的区别是发展CVI的关键的第一步 专门为照顾患有这种疾病的儿童而设计的神经康复框架。这真是太棒了 对CVI患者的意义；尽管CVI很重要，但服务严重不足的人群

Summary The objective of the proposed research is to better understand the underlying neurophysiology of cerebral/cortical visual impairment (CVI), the leading cause of congenital vision loss in the United States and developed world. CVI is associated with peri-natal damage to visual cerebral structures and pathways, and leads to a myriad of impairments in visual function. Despite this alarming public health issue, there is a fundamental gap in our understanding as to how the visual system develops in the setting of cerebral compared to ocular based visual impairment. Current studies using standard clinical imaging modalities are limited in their ability to characterize brain functional reorganization in the setting of widespread neurological injury. To further advance our understanding, we will employ multi-modal neuroimaging to characterize whole brain as well as regional structural and functional brain connectivity in CVI associated with periventricular leukomalacia (PVL). In our first aim, we will characterize white matter integrity and structural connectivity using high angular resolution diffusion imaging (HARDI). In our second aim, we will characterize functional brain connectivity networks using resting state functional connectivity (rsfc)MRI. Using a graph theoretical analysis framework, we will then investigate network topological properties and the coupling between structural and functional networks. Further characterization of functional connectivity will be carried out using stepwise functional connectivity (SFC) analysis. This complementary approach allows for the investigation of widespread network alterations on information transfer across the entire brain, and represents a key distinguishing innovation of this proposal. Specifically, the examination of topological characteristics and the nature of structural-functional network coupling will lead to a better understanding of CVI by uncovering the nature of network alterations in the setting of congenital brain injury and how it relates to visual function. Findings will be compared to ocular visually impaired (OVI) individuals (matched for residual visual function) as well as neurotypical sighted controls. Our overarching hypothesis is that CVI is associated with key differences in the organization and relationship between structural-functional connectivity networks. Furthermore, we predict that in CVI, functional networks responsible for visual processing will show evidence of reorganization in response to large-scale white matter injury, and this may serve as a useful biomarker in relation to clinical functional assessments. This study will provide a high level of insight that has not been previously achieved by previous investigations relying on standard clinical imaging approaches. Uncovering how the brain develops in the case of CVI and how it differs from ocular based visual impairment is a crucial first step in developing a neurorehabilitative framework specifically designed for the care of children with this condition. This is of great significance for individuals with CVI; a population that has been immensely underserved despite its important