Adaptive Neuroplasticity Following Central Visual Field Loss in Macular Degeneration

黄斑变性中央视野丧失后的适应性神经可塑性

• 批准号: 9982697
• 负责人: Leland Fleming
• 金额: $ 3.95万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-31 至 2021-07-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9982697
• 关键词: Address; Adult; Affect; Age; American; Area; Award; Behavior Therapy; Behavioral; Blindness; Brain; Brain Mapping; Brain region; Categories; Central Scotomas; Competence; Data; Data Collection; Deterioration; Development; Disease; Doctor of Philosophy; Doctor' s Degree; Event; Face; Human; Individual; Intervention; Knowledge; Learning; Letters; Literature; Macular degeneration; Magnetic Resonance Imaging; Manuscripts; Mentorship; Methodology; Methods; Modernization; Nature; Neural Pathways; Neurites; Neuronal Plasticity; Neurosciences; Participant; Patients; Performance; Peripheral; Phase; Photoreceptors; Population; Publishing; Qualifying; Quality of life; Reading; Rehabilitation therapy; Research; Research Personnel; Research Project Grants; Research Training; Resolution; Retina; Retinal Diseases; Stimulus; Structure; Techniques; Testing; Therapeutic Intervention; Thick; TimeLine; Training; United States National Institutes of Health; Vision; Visual; Visual Cortex; Visual Fields; Visual impairment; Visual system structure; Work; Writing; area striata; base; brain remodeling; computational neuroscience; critical period; density; design; experience; extrastriate visual cortex; improved; insight; macula; neuroimaging; neuromechanism; neurotransmission; novel strategies; programs; signal processing; skills; symposium; visual information; visual performance; visual processing; visual stimulus

ABSTRACT Macular degeneration (MD) is retinal disease that causes severe visual impairment in nearly 7 million people in the U.S. This disease causes the progressive deterioration of photoreceptors in the center of the retina, known as the macula, and renders patients unable to see in the center of the visual field. As a consequence, patients with MD must rely on peripheral vision, making even the simplest everyday tasks, such as reading or recognizing faces, much more difficult. Reliance on peripheral vision is extremely problematic, as it possesses substantially lower resolution compared to central vision. In fact, many patients never fully adapt to using peripheral vision effectively. Interestingly, however, some patients become particularly skilled at using their spared peripheral vision. Prior work suggests that this adaptation to using peripheral vision happens at a processing stage beyond the retina, specifically in visual cortex. There is debate in the literature about whether or not brain regions that formerly responded to central (lost) vision remap their function to respond to peripheral (spared) vision. We address a different form of plasticity here: remodeling of the brain regions which originally responded to peripheral (spared) vision so that they are more capable of taking on the functions of central vision. Our hypothesis is that peripherally-representing visual cortex builds new connections after experience, and this changes the structure and function of that region. Using neuroimaging (Magnetic Resonance Imaging) in human participants, we have generated preliminary evidence that suggests that some of these changes may exist in the form of alterations to brain structure (neurite density and cortical thickness) and brain function (functional connectivity). For example, we have observed that the parts of visual cortex that respond to peripheral vision have greater cortical thickness in MD patients compared to healthy controls, suggesting a possible compensatory mechanism that may be associated with enhanced use of peripheral vision. Additionally, we have observed that peripheral regions of early visual cortex in MD patients are more strongly functionally connected to later visual areas that selectively respond to specific types of visual stimuli, such as facial features and words/letters. We will test the hypothesis that better use of peripheral vision in MD is associated with enhanced functional connectivity and enhanced structure (neurite density and cortical thickness). More specifically, we predict that enhanced visual function in MD will be related to stronger functional connectivity between peripheral areas of primary visual cortex and later visual areas that respond preferentially to categories of stimuli (i.e.- faces, and words). Additionally, we predict that greater neurite density and cortical thickness in primary visual cortex will be related to behavioral performance on visual processing tasks. These findings will help provide insight towards improving therapeutic interventions for MD, as well as uncover knowledge about the adult brain’s potential for adaptation to changes in experience.

抽象的 黄斑变性（MD）是视网膜疾病，可导致近700万人的严重视觉障碍 美国这种疾病会导致感光体在视网膜中心的逐渐影响，已知 作为黄斑和黄斑，使患者无法在视野的中心看到。结果，患者 使用MD必须依靠外围视觉，即使是每天最简单的任务，例如阅读或 认识到面孔，更加困难。依赖外围视力是极其问题的，因为它拥有 与中央视觉相比，分辨率大大降低。实际上，许多患者从不完全适应 有效的外围视力。然而，有趣的是，有些患者变得特别擅长使用他们的 宽松的外围视力。先前的工作表明，这种对使用外围视觉的适应发生在 在视网膜之外的处理阶段，特别是在视觉皮层中。文献中有关于 以前对中央（丢失）视力反应的大脑区域是否重现其功能以回应 外围（幸免）视觉。我们在这里解决了另一种可塑性：大脑区域的重塑 最初对外围（幸福的）视力做出了反应 中央视力的功能。我们的假设是，外围代表性的视觉皮层建立了新的 经验后的连接，这改变了该区域的结构和功能。使用神经影像学 （磁共振成像）在人类参与者中，我们产生了初步证据 这些变化中的某些可能以对大脑结构的改变的形式（神经突密度和皮质 厚度）和大脑功能（功能连通性）。例如，我们观察到视觉的部分 与健康相比 控件，表明可能与增强使用有关的可能的补偿机制 外围视力。此外，我们观察到MD患者早期视觉皮层的周围区域 功能更强地连接到后来的视觉区域，这些视觉区域有选择地响应特定类型的视觉 刺激，例如面部特征和单词/字母。我们将测试更好地使用外围的假设 MD中的视觉与增强的功能连接性和增强结构（神经突）有关 密度和皮质厚度）。更具体地说，我们预测MD中增强的视觉功能将是 与主要视觉皮层的外围区域和后来的视觉 优选地对刺激类别（即面孔和单词）做出反应的领域。此外，我们预测 一级视觉皮层的更大神经密度和皮质厚度将与行为性能有关 关于视觉处理任务。这些发现将有助于提供改善治疗干预措施的见解 对于MD，以及有关成人大脑适应经验变化的潜力的知识。