Neurophysiological Correlates of Visual Motion Processing in Cerebral Visual Impairment

总结 大脑（皮质）视力障碍（CVI）是美国先天性视力障碍的主要原因。 States.然而，在我们的理解中，关于观察到的视觉感知缺陷是如何发生的， 在这些个体中与围产期损伤和中央视觉通路的早期发育不良有关， 结构.患有CVI的儿童和青少年在复杂的运动处理中表现出明显的损伤（a 背流函数），特别是在复杂动态环境场景的设置中。在身体受损时 运动知觉是发育脆弱性的重要标志（称为背流 功能障碍假说），标准眼科临床评估未能捕获和充分表征这些 视觉缺陷因此，在没有任何明显的眼部异常的情况下，临床医生可能会忽略报告的 知觉困难，许多患有CVI的人将仍然未被诊断，永远不会得到及时的治疗。 他们需要的教育和康复支持这项研究的目的是调查 与CVI中运动处理缺陷相关的潜在神经生理学。我们会对他进行心理物理检查 结合多模式神经成像的行为测试（以表征结构和功能 与脑血管病相关的儿童和青少年中的脑血管连通性沿着大脑网络激活） 脑室周围白质软化（PVL）。行为表现和神经影像学结果的指数将 与正常对照组相比。我们的总体假设是，运动处理缺陷将是 与关键视觉处理通路的发育不良有关。然而，改变的模式 涉及复杂运动感知的大脑网络的功能连接和激活可以作为 代偿性神经可塑性的指标在我们的第一个目标，我们将评估运动处理能力， 随机点运动图、虚拟现实模拟和视觉搜索任务。在我们的第二个目标中，我们将 表征结构和功能连接网络的完整性和拓扑结构（使用高角度 分辨率弥散成像和静息态功能磁共振成像）与视觉运动和注意力有关 处理.第三个目标将研究大脑网络激活（使用功能性MRI），以响应我们的研究。 行为任务评估。由具有强大社区的多学科研究团队执行 参与，这种结合行为评估和多模式成像方法代表了一个关键 突出提案创新。这项研究将提供聚合和高层次的见解， 视觉运动知觉缺陷的神经生理学基础。拟议的研究计划是 非常重要的是，在CVI的情况下，揭示大脑行为的关联是一个至关重要的 建立专门为照顾这些儿童设计的神经康复框架的步骤; 尽管人口的重要性很大，

Summary Cerebral (cortical) visual impairment (CVI) is the leading cause of congenital vision impairment in the United States. Yet, there remains an alarming gap in our understanding as to how observed visual perceptual deficits in these individuals relate to perinatal damage and early maldevelopment of central visual pathways and structures. Children and adolescents with CVI show striking impairments in complex motion processing (a dorsal stream function), particularly in the setting of complex dynamic environmental scenes. While impaired motion perception is an important marker of developmental vulnerability (referred to as the dorsal stream dysfunction hypothesis), standard ophthalmic clinical assessments fail to capture and fully characterize these visual deficits. Thus, in the absence of any apparent ocular abnormality, clinicians may dismiss reported perceptual difficulties, and many individuals with CVI will remain undiagnosed and never receive the timely education and rehabilitative support they need. The objective of the proposed research is to investigate the underlying neurophysiology associated with motion processing deficits in CVI. We will carry out psychophysical behavioral testing combined with multimodal neuroimaging (to characterize structural and functional connectivity along with brain network activation) in children and adolescents with CVI associated with periventricular leukomalacia (PVL). Indices of behavioral performance and neuroimaging outcomes will be compared to neurotypical controls. Our overarching hypothesis is that motion processing deficits will be associated with the maldevelopment of key visual processing pathways. However, altered patterns of functional connectivity and activation of brain networks implicated in complex motion perception may serve as indicators of compensatory neuroplasticity. In our first aim, we will assess motion processing abilities using random dot kinematograms, virtual reality simulations, and visual search tasks. In our second aim, we will characterize the integrity and topology of structural and functional connectivity networks (using high angular resolution diffusion imaging and resting state fMRI respectively) implicated with visual motion and attention processing. The third aim will investigate brain network activation (using functional MRI) in response to our behavioral task assessments. Executed by a multidisciplinary research team with strong community involvement, this combined behavioral assessment and multimodal imaging approach represents a key distinguishing innovation of the proposal. This study will provide convergent and high-level insights into the neurophysiological basis of visual motion perceptual deficits in CVI. The proposed program of research is highly significant given that uncovering brain-behavioral associations in the case of CVI represents a crucial step in establishing a neurorehabilitative framework specifically designed for the care of these children; a population that has been greatly underserved despite its important