CRCNS: investigating perceptual processing speed and its impact on choice behavior

项目概要/摘要 该项目的目标是研究感知信息引导神经机制 选择下一步去哪里；具体来说，我们建议记录紧急决策过程中的神经元活动 以精细的时间分辨率检查感知如何影响运动规划。神经科学家通常 通过做出感知判断并随后进行运动报告的任务来研究选择行为，但是 这种方法有局限性。首先，它允许各种隐蔽因素，例如注意力、预期或任务差异 邪教相互交易，造成了无法通过标准心理物理学解决的模糊性 指标，即反应时间和选择准确性。其次，序列化抑制了快速的、相互的相互作用。 知觉分析和运动规划之间的动作，通常会产生明智的扫视选择。 我们的方法基于最近开发的一项任务，其中决策是紧急的，并且这两个问题 被最小化。我们的框架还包括一个启发式的、基于生理学的模型，可以重现 对象的丰富行为和细节。因此，我们建议研究感知如何影响运动规划 利用时间压力将这些过程纳入其自然时间尺度和动态范围内，并将它们联系起来 定量地反映心理物理表现。将记录经过训练的猴子的动眼神经活动 执行我们紧急选择范例的几种变体。在目标 1 中，我们将研究之间的关系 通过改变目标和干扰物的相对显着性来进行外源（或自下而上）注意力和运动规划 在紧急选择的时候。我们假设反射性、显着性驱动的注意力形式通过两种方式起作用： 具体机制：加速与其空间一致的正在进行的运动计划，并停止 这些计划在空间上不一致。在目标 2 中，我们将研究注意力之间的关系， 运动计划，以及通过训练猴子执行紧急版本来积累感官证据 众所周知的随机点运动辨别任务。在这种情况下，因为两个选择的位置 目标与要区别对待的刺激目标是分离的，我们期望观察到之间的权衡 刺激驱动的活动（表明对刺激的注意力的部署）和目标驱动的活动（信号 分析即将发生的眼球运动）。我们之前和当前的初步结果表明我们将 能够解决感知信号和持续的运动活动之间精心策划的相互作用 展开速度非常快，只需几十毫秒，否则在实验上是无法实现的。我们将利用 这种能力可以区分额叶视野 (FEF) 和横向内视野之间的基本功能区别 顶叶区 (LIP)，并确定经典细胞类型（视觉、视觉运动和 运动）到每个关键动眼结构内的感知引导选择。这项工作将提供 关于感知信息如何动态地融入正在进行的运动活动的批判性见解，以及 这种相互作用如何决定扫视选择的表现。

Project Summary/Abstract The goal of this project is to investigate the neural mechanisms whereby perceptual information guides the choice of where to look next; specifically, we propose to record neuronal activity during urgent decision making to examine with fine temporal resolution how perception informs motor planning. Neuroscientists normally study choice behavior with tasks in which a perceptual judgment is made and is followed by a motor report, but this approach has limitations. First, it allows various covert factors such as attention, anticipation, or task diffi- culty to be traded against each other, creating ambiguities that cannot be resolved via standard psychophysical metrics, i.e., reaction time and choice accuracy. And second, serialization suppresses the rapid, reciprocal inter- action between perceptual analysis and motor planning from which informed saccadic choices normally arise. Our approach is based on a recently developed task in which decisions are urgent and both of these problems are minimized. Our framework also includes a heuristic, physiologically grounded model that reproduces the subjects' rich behavior with great detail. Thus, we propose to study how perception informs motor planning using time pressure to engage these processes within their natural time scale and dynamics, and relate them quantitatively to psychophysical performance. Oculomotor activity will be recorded from monkeys trained to perform several variants of our urgent choice paradigm. In Aim 1 we will investigate the relationship between exogenous (or bottom-up) attention and motor planning by varying the relative salience of target and distracter during an urgent choice. We hypothesize that the reflexive, salience-driven form of attention acts through two specific mechanisms: acceleration of ongoing motor plans that are spatially congruent with it, and halting of those plans that are spatially incongruent. In Aim 2 we will investigate the relationship between attention, motor planning, and accumulation of sensory evidence by training monkeys to perform an urgent version of the well known random-dot motion discrimination task. In this case, because the locations of the two choice targets are dissociated from that of the stimulus to be discriminated, we expect to observe a tradeoff between stimulus-driven activity (signaling the deployment of attention to the stimulus) and target-driven activity (sig- naling the impending eye movement). Our previous and current preliminary results indicate that we will be able to resolve exquisitely orchestrated interactions between perceptual signals and ongoing motor activity that unfold very rapidly, within a few tens of ms, and are otherwise experimentally inaccessible. We will exploit this capability to draw essential functional distinctions between the frontal eye field (FEF) and the lateral intra- parietal area (LIP), and to determine the distinct contributions of classical cell types (visual, visuomotor, and motor) to perceptually guided choices within each of these key oculomotor structures. This work will provide critical insight about how perceptual information is dynamically incorporated into ongoing motor activity, and how this interaction determines saccadic-choice performance.