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 国家。然而，对于如何观察到视觉感知缺陷，我们的理解仍然存在令人震惊的差距 这些个体与围产期损伤和中央视觉通路早期发育不良有关 结构。患有 CVI 的儿童和青少年在复杂运动处理方面表现出明显的障碍（a 背流功能），特别是在复杂动态环境场景的设置中。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并充分表征这些 视力缺陷。因此，在没有任何明显的眼部异常的情况下，临床医生可能会驳回报告 知觉困难，许多患有 CVI 的人仍未得到诊断，也从未得到及时的治疗 他们需要的教育和康复支持。拟议研究的目的是调查 与 CVI 运动处理缺陷相关的潜在神经生理学。我们将进行心理物理 行为测试与多模式神经影像相结合（以表征结构和功能 患有 CVI 的儿童和青少年的连接性以及大脑网络激活） 脑室周围白质软化症（PVL）。行为表现和神经影像结果的指数将是 与神经典型对照相比。我们的首要假设是运动处理缺陷将 与关键视觉处理通路发育不良有关。然而，改变了模式 与复杂运动感知有关的大脑网络的功能连接和激活可能可以作为 代偿性神经可塑性指标。在我们的第一个目标中，我们将使用以下方法评估运动处理能力 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（使用高角度 分辨率扩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 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，这种结合的行为评估和多模态成像方法代表了一个关键 提案的创新点突出。这项研究将为 CVI 中视觉运动知觉缺陷的神经生理学基础。拟议的研究计划是 鉴于揭示 CVI 情况下的大脑行为关联是至关重要的，因此这一点非常重要。 建立专门为照顾这些儿童而设计的神经康复框架的步骤；一个 尽管其重要，但服务却严重不足的人口

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