HIERARCHICAL PROCESSING IN THE MOTION SYSTEM

这个实验室的总体研究目标有两个：探索 灵长类视觉信息加工的基本机制 并研究这种信息处理是如何作为一种 用于视觉感知和视觉引导行为的基板。对于几个人来说 猕猴背侧纹外皮质的“运动系统” 形成了一个很好的提问模式系统。首先， 这条通路上区域的基本解剖学和生理学是很好理解的。 其次，从几个实验室最近的工作中可以知道 这条通路上的生理事件与知觉密切相关 视觉运动。最后，似乎很可能有一条类似的路径 功能也存在于人类视皮层中，因此信息 我们从猴子那里获得的信息将帮助我们理解人类的视觉 信息处理及其障碍。 纹外皮质信息处理的一般规律 是复杂反应特性在后期阶段的详细阐述 正在处理。这项拨款中提出的研究将对此进行调查。 运动系统中的分层处理，并询问有什么新奇的行为 神经元的复杂属性支持能力 纹外区MST，可以说是最高级别的区域 神经元信号主要是视觉信号，而不是视觉运动信号。 实验将在警觉的恒河猴身上进行，允许 同时测量生理和行为事件。两种 将进行一系列的实验，每个实验都针对一个长期的- 以上所述的任期目标： L)单细胞生理学实验将探索 运动通路上两个区神经元的反应特性 MST是由反应更简单的神经元的信号建立起来的 较早级别的属性。这些实验将使用新的视觉 刺激探索感受野(RF)之间的相互作用 负责生成已知RF属性的子区域。 2)结合行为和生理实验将阐明 MST内神经元的复杂反应特性与行为任务相关 依赖于对复杂运动模式的分析。猴子将会是 经过训练以辨别复杂的运动流场并检测其 “前进方向”的基础上这样的领域。神经元敏感性将 在动物执行这些任务时被测量，以及微刺激 实验将确定神经信号的操纵是否会影响 任务绩效。 这两个项目加在一起，应该揭示出 灵长类运动系统中的分层信息处理 说明这一过程的后期阶段的行为作用。

The overall goals of research in this laboratory are twofold: exploring the basic mechanisms of visual information processing in primate visual cortex and investigating how this information processing serves as a substrate for visual perception and visually guided behavior. For several reasons, the "motion system" of dorsal extrastriate cortex in monkeys forms an excellent model system in which to ask such questions. First, the basic anatomy and physiology of areas on this pathway are well understood. Secondly, it is known from recent work in several laboratories that physiological events on this pathway are closely related to the perception of visual motion. Lastly, it seems very likely that a pathway with similar functions exists in human visual cortex as well, so that the information we obtain from the monkey will help us to understand human visual information processing and its disorders. A seemingly general rule of information processing in extrastriate cortex is the elaboration of complex response properties at later stages of processing. The research proposed in this grant will investigate this hierarchical processing in the motion system and ask what novel behavioral capabilities are supported by the complex properties of neurons in extrastriate area MST, which is arguably the highest-order area where neuronal signals are dominantly visual, as opposed to visuomotor. Experiments will be performed on the alert rhesus monkey, allowing simultaneous measurement of physiological and behavioral events. Two kinds of experiments will be performed, each directed towards one of the long- term objectives stated.above: l) Single-cell physiology experiments will probe the manner in which the response properties of neurons in two areas on the motion pathway, MT and MST, are built up from the signals of neurons with the simpler response properties of earlier levels. These experiments will employ novel visual stimuli to explore the interactions between receptive field (RF) subregions responsible for generating known RF properties. 2) Combined behavior and physiology experiments will elucidate how the complex response properties of neurons in MST relate to behavioral tasks dependent on the analysis of complex motion patterns. Monkeys will be trained to discriminate complex motion flow fields and to detect their "heading direction" on the basis of such fields. Neuronal sensitivity will be measured as the animal performs these tasks, and microstimulation experiments will determine if manipulation of neuronal signals affects task performance. Together, these two projects should reveal basic mechanisms of hierarchical information processing in the primate motion system and illuminate the behavioral role of the later stages of this processing.