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

项目摘要/摘要 这个项目的目标是研究神经机制，感知信息通过这种机制引导 选择下一步看哪里；特别是fi，我们建议记录紧急决策过程中的神经元活动 用fiNe时间分辨率研究知觉如何影响运动规划。神经学家通常 通过任务来研究选择行为，在任务中做出感知判断，然后是运动报告，但是 这种方法有其局限性。首先，它允许各种隐蔽因素，如注意力、预期或任务差异fi- 邪教相互交易，制造不能通过标准心理物理解决的模棱两可 指标，即反应时间和选择的准确性。其次，串行化抑制了快速的、相互的 在知觉分析和运动规划之间的行动，通常会产生明智的眼跳选择。 我们的方法是基于最近开发的一项任务，在该任务中决策是紧急的，这两个问题 被最小化了。我们的框架还包括一个启发式的、基于生理的模型，该模型再现了 受试者丰富的行为细节。因此，我们建议研究知觉如何影响运动规划。 利用时间压力在自然的时间尺度和动态范围内参与这些过程，并将它们联系起来 从数量上讲与心理物理表现有关。将记录受过训练的猴子的眼球运动活动 执行我们紧急选择范式的几个变种。在目标1中，我们将调查 通过改变目标和分心者的相对显著程度来实现外源性(或自下而上)注意和运动规划 在一个紧急的选择中。我们假设Refl存在的、显著驱动的注意形式通过两个 SPECIfic机制：加速正在进行的与其空间一致的运动计划，并停止 那些在空间上不协调的计划。在目标2中，我们将调查注意力与 运动计划，并通过训练猴子执行紧急版本的 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 目标与要区分的刺激的目标是分离的，我们希望观察到在 刺激驱动的活动(发出对刺激的注意的信号)和目标驱动的活动(sig- 捕捉即将到来的眼球运动)。我们之前和目前的初步结果表明，我们将 能够解决感知信号和正在进行的运动活动之间的精心编排的交互， 在几十毫秒内非常迅速地展开，否则在实验中是不可访问的。我们将利用 这种在额眼field(FEF)和外侧眼内区之间区分基本功能的能力-- 顶区(LIP)，并确定经典细胞类型(视觉、视觉运动和 这些关键的动眼神经结构中的每一个都有感知引导的选择。这项工作将提供 对感知信息如何动态地结合到正在进行的运动活动中的关键洞察力，以及 这种互动如何决定跳动选择的表现。

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.