HEIRARCHICAL PROCESSING IN THE MOTION SYSTEM

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 目标：视觉感知的基本“构件”开始变得相当好地被理解，我们可以很好地解释简单的辨别是如何进行的。我们对视觉系统如何解决更现实的日常挑战的了解要少得多。视觉导航是在实验室研究真实世界视觉过程的一个特别好的“模型系统”。视网膜上的运动模式对自我运动的感知已经得到了广泛的研究，尽管我们仍然对大脑中关键的处理步骤发生在哪里，以及复杂的运动模式如何转化为有效的运动知之甚少。本建议旨在回答这些悬而未决的问题。首先，我们将通过使用多种同步记录技术，在我们的实验动物进行自我运动方向的辨别时，寻找多个皮质区域参与自我运动感知的直接证据。其次，我们将寻求询问顶叶皮质区域(顶叶腹侧区域或VIP)是否既是自我运动感知所必需的，也是实际使用的。我们将通过在自我运动任务的背景下扰乱VIP中的活动模式来做到这一点，既有可逆的失活，也有电激活。这些互补的方法应该会极大地扩展我们对顶叶皮质如何参与自我运动感知的理解。然而，为了真正扩展我们对自我运动感知的知识，我们需要将调查扩展到更积极的背景下。人的因素研究表明，自我运动的引导(“转向”)是一个非常活跃的过程，凝视的方向是一个关键组成部分。然而，对这项主动任务中使用的中枢神经系统机制几乎一无所知。因此，我们建议建立、表征和开发一种主动运动的动物模型，以研究脑结构在这一任务中的参与。我们将训练受试者通过操纵杆引导他们的“虚拟”轨迹，并表征他们的正常行为如何受到目标方向、凝视方向、凝视速度和视觉运动信息等线索的影响。然后，我们将记录动物参与这项任务时多个大脑皮层区域的活动，并探索视觉和顶叶皮质的信号，以更好地理解视觉导航的大脑机制。从长远来看，这些信息可能有助于帮助残疾人导航，并有助于盲人视觉假肢的开发。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objective: The basic "building blocks" of visual perception are starting to become reasonably well understood, and we can make a fairly good account of how simple discriminations are done. What we understand much less is how the visual system solves more realistic, everyday challenges. Visually guided navigation is a particularly good "model system" for studying real-world visual processes in the laboratory. The perception of self-motion from the pattern of motion on the retina has been studied extensively, though we still know very little about where in the brain the critical processing steps occur, and how the complex pattern of motion is converted into effective movement. The present proposal seeks to answer these open questions. First, we will seek direct evidence for the involvement of multiple cortical areas in the perception of self-motion, by using multiple, simultaneous recording techniques while our experimental animals are performing a discrimination of self-motion direction. Secondly, we will seek to ask if the parietal cortical area (the ventral intraparietal area or VIP) is both necessary for self-motion perception and is actually used. We will do this by perturbing the pattern of activity in VIP in the context of the self-motion task, both by reversible inactivation as well as by electrical activation. These complementary methods should greatly extend our understanding of how the parietal cortex participates in self-motion perception. However, to really extend our knowledge of self-motion perception, we need to extend the inquiry into a more active context. Human-factors studies have revealed that guidance of self-motion ("steering") is a very active process, with the direction of gaze being a critical component. However, next to nothing is known about the central nervous system mechanisms used in this active task. So, we propose to establish, characterize and exploit an animal model of active locomotion to study the involvement of brain structures in this task. We will train our subject to direct their "virtual" trajectories by joystick, and characterize how their normal behavior is influenced by cues including target direction, gaze direction, gaze velocity, and visual motion information. We will then record activity in multiple cortical areas while animals are engaged in this task, and explore the signals in visual and parietal cortex to better understand brain mechanisms of visually guided navigation. This information, in the long term, might be useful in helping the disabled to navigate, and in the development of visual prosthetics for the blind.