Effects of Parkinson's Disease on Perception, Cognition, and Gait

帕金森氏病(PD)的非运动方面，如感觉、知觉和认知不足，是一种 日常功能和生活质量显著下降的根源。最重要的每日新闻之一 受帕金森病影响的功能是视空间能力，它使知觉和认知能力 对视觉环境的理解和导航。这个领域的缺陷是由病理性的 大脑高阶关联区的变化以及来自更基本视觉的有缺陷的输入 加工区，反映皮质纹状体环的特定方面的功能障碍。对…有潜在的重要性 理解帕金森病的视觉空间后遗症是考虑作为帕金森病患者的初始运动障碍的一面 几乎总是有单侧神经变性的发作，尤其是右脑 视觉空间处理的许多方面。我们的目标是定义基本视觉和视觉空间之间的关系 帕金森病的问题和检查潜在的神经变化。特别是，我们的目标是阐明 视觉空间认知中特定的皮质纹状体结构和确定特定脑区之间的功能连接 皮质区域和纹状体区域。我们假设，首先，帕金森病患者的认知障碍反映了 波及尾状回的皮质纹状体环。第二，我们假设运动症状的一侧 视觉刺激的起始和半视野表现可预测大脑半球的低活动性。 皮质纹状体环，对起病于左侧(LPD)(右侧)的患者影响更大 神经节)和左侧视觉半视野呈现。我们的第三个焦点是视觉和视觉空间的关系 日常功能障碍，包括步态、运动冻结、主观生活质量、幻觉、情绪 以及PD的其他以患者为中心的特征。为了实现我们的目标，我们将汇集科学家的专业知识。 来自互补学科，包括神经心理学、视觉心理物理学、认知神经科学和 神经成像和临床运动学。我们建议的功能磁共振成像研究提供了对 假设皮质纹状体环的特定成分功能障碍，特别是额纹状体和 顶纹状体环，是帕金森病患者特定视觉空间和视觉认知任务的潜在问题。就像大多数 皮质区域与纹状体相连，这些研究将填补在理解可能的 皮质纹状体回路在认知中的普遍作用。心理物理、认知和成像技术的应用 可以预测帕金森病患者高级认知和日常功能完整性的技术将是有用的 在临床上，使患者能够在诊断时识别潜在的空间问题。我们的测试目标是 由患者自己报告的视觉、视觉空间和功能症状，确保 机制的阐明将具有临床意义。

Non-motor aspects of Parkinson's disease (PD) such as deficient sensation, perception, and cognition are a source of a significant decline in everyday function and quality of life. Among the most important of daily functions that is affected in PD is visuospatial ability, which enables the perceptual and cognitive comprehension and navigation of the visual environment. Deficits in this domain arise from pathological changes in high-order association areas of the brain as well as from defective input from more basic visual processing areas, reflecting dysfunction of specific aspects of corticostriatal loops. Of potential importance to understanding the visuospatial sequelae of PD is consideration of the side of initial motor impairment, as PD nearly always has unilateral onset of neurodegeneration, and the right hemisphere is especially engaged in many aspects of visuospatial processing. We aim to define the relation between basic vision and visuospatial problems in PD and to examine underlying neural changes. In particular, we aim to elucidate the causal role of specific corticostriatal structures in visuospatial cognition and to define functional connectivity between specific cortical areas and striatal regions. We hypothesize, first, that cognitive impairments in PD reflect dysfunction in corticostriatal loops involving the rostrodorsal caudate. Second, we hypothesize that side of motor symptom onset as well as hemifield presentation of visual stimuli predict the hemispheric laterality of hypoactivation in corticostriatal loops, with stronger effects for patients with onset on the left body side (LPD) (right basal ganglia) and for left visual hemifield presentation. Our third focus is on the relation of visual and visuospatial impairments to daily function, including gait, motoric freezing, subjective quality of life, hallucinations, mood and other patient-centered features of PD. To accomplish our goals, we will marshal the expertise of scientists from complementary disciplines, including neuropsychology, visual psychophysics, cognitive neuroscience and neuroimaging, and clinical movement science. Our proposed fMRI studies provide a direct test of the hypothesis that dysfunction in specific components of corticostriatal loops, especially frontostriatal and parietostriatal loops, underlie problems on specific visuospatial and visuocognitive tasks in PD. As most cortical regions are connected with the striatum, the studies will fill a significant gap in understanding the likely ubiquitous role of corticostriatal circuits in cognition. The application of psychophysical, cognitive and imaging techniques that could predict the integrity of higher-level cognitive and daily functions in PD will be useful clinically, enabling the identification of potential spatial problems for the patient at diagnosis. Our tests target visual, visuospatial, and functional symptoms reported by the patients themselves, ensuring that the elucidation of mechanisms will have clinical relevance.