NEURAL MECHANISMS OF TACTILE SPATIO-TEMPORAL INTEGRATION

这个提议描述了一系列在人类和猴子身上的实验，研究触觉时空有序刺激的神经整合。 拟议研究的一个基本目标是在皮层区域的激活水平上理解这种神经处理，以及在这些区域内的特定模式神经元活动水平上理解这种神经处理。 为了实现这一目标，将使用功能性磁共振成像（fMRI）来绘制人类躯体感觉皮层，并使用多电极记录来记录猴子躯体感觉皮层中的神经反应模式。 该项目有三个具体目标。 第一，定义由触觉运动刺激激活的人类皮层区域。 在3特斯拉功能磁共振成像扫描仪中使用事件相关设计将允许映射为个体行为反应的函数。 第二，研究快速神经整合的触觉运动刺激在猴子/中央后回（POCG）和更高的皮质区。多电极记录技术将记录在触觉表观运动刺激呈现期间从超过毫米的皮层放电的动作电位模式。 这将允许分布式编码方案的分析和个人触觉感受野的组织。 第三，检查在时空有序的刺激过程中皮层的激活，这些刺激不会引起对运动的感知。 使用功能磁共振成像和多电极技术，我们将检查皮层激活引起的连续的刺激，从明显的运动刺激感知稳定的刺激。 通过映射这些激活模式，我们将深入了解支持运动感知的神经编码的出现，以及支持各种时空感知交互的神经机制。 这些研究将扩大我们对快速时空触觉整合的理解，这是成功触觉假肢设计中的一个重要课题。此外，他们将提供人类和猴子神经处理之间的直接比较，这种比较将扩大我们对人类功能与最重要的临床和科学模型系统（非人类灵长类动物）之间联系的了解。

This proposal describes a series of experiments in humans and monkeys that investigate neural integration of tactile spatio- temporally ordered stimuli. A fundamental goal of the proposed research is to understand this neural processing at the level of activation of cortical areas, and at the level of specific patterns neuronal activity within those areas. To achieve this goal, functional magnetic resonance imaging (fMRI) will be used to map the human somatosensory cortex, and multi-electrode recording will be used to record neural response patterns in the monkey somatosensory cortex. This project has three specific aims. First, to define human cortical areas activated by tactile motion stimuli. Use of an event-related design in a 3 Tesla fMRI scanner will permit mapping as a function of individual behavioral responses. Second, to examine rapid neural integration of tactile motion stimuli in the monkey/postcentral gyrus (PoCG) and a higher cortical area. Multi-electrode recording techniques will record patterns of action potential firing from over millimeters of the cortex during the presentation of tactile apparent motion stimuli. This will permit the analysis of distributed coding schemes and the organization of individual tactile receptive fields. Third, to examine cortical activation during spatio-temporally ordered stimuli that do not evoke the percept of motion. Using fMRI and multi-electrode techniques, we will examine cortical activation evoked by a continuum of stimuli, ranging from apparent motion stimuli to perceptually stable stimuli. By mapping these activation patterns, we will gain insight into both the emergence of neural coding supporting motion perception, and into the neural mechanisms, that support a variety of spatio-temporal perceptual interactions. These studies will expand our understanding of rapid spatio-temporal tactile integration, an important topic in the design of successful tactile prosthetics. Further, they will provide direct comparisons between the neural processing in humans and monkeys, a comparison that will expand our knowledge of the connections between human function and the most important clinical and scientific model system, the non-human primate.