Neural time-integration underlying higher cognitive function

描述（由申请人提供）：时间整合可能是大脑产生灵活和智能行为的关键步骤，这些行为与感觉处理或运动执行的即时时间尺度无关。这项研究计划旨在通过建立灵长类动物背流和视觉运动处理的开创性研究来解开高级认知功能的神经计算。在心理物理学，神经生理学和计算的综合框架内，我们的目标是提出关于如何“读出”短暂的感觉信号以指导行为的精确问题，并获得跨越单个神经元，神经回路和心理计算水平的答案。这项工作致力于了解在各种心理健康和大脑老化条件下恶化的基本机制。 目标1.从刺激到决策的时间整合的精确表征，在心理物理学和跨MT和LIP的同时多神经元/多区域记录期间使用反向相关协议，并通过广义线性模型进行解释。 没有实证研究已经测试了假设的时间整合MT信号的LIP与直接测量，我们将通过同时记录从MT和LIP神经元集。目标二。这个（假定的）决策回路的因果询问，扩展了上述MT-LIP框架，包括一个区域的可逆失活，并辅之以另一个区域的并发多神经元记录。将LIP与决策联系起来的证据几乎完全是相关的。我们建议对该区域进行灭活，以测试其在证据积累中的因果或必要作用。 目标3。分析眼决策的多个阶段，将上述目标中描述的多神经元/多区域和灭活和记录方法应用于LIP-FEF-PFC。虽然在LIP记录的同时直接测量MT中的感觉信号可能会给我们带来重要的新见解，支持运动辨别的神经信号几乎肯定跨越具有许多感觉和认知阶段的较大回路。在这里，我们建议应用上述技术来阐明后顶叶和前额叶在决策中的相对作用。

DESCRIPTION (provided by applicant): Temporal integration may be the brain's key step in generating flexible and intelligent behaviors that are divorced from the immediate time scales of sensory processing or motor execution. This research program aims to unpack the neural computations that underlie higher cognitive function by building off seminal studies in the primate dorsal stream and visual motion processing. Within an integrated framework of psychophysics, neurophysiology, and computation, we aim to ask precise questions about how fleeting sensory signals are "read out" to guide behavior, and to arrive at answers that span the levels of single neurons, neural circuits, and mental computations. This work strives to understand the basic mechanisms that deteriorate in a variety of mental health and brain aging conditions. Aim 1. Precise characterization of temporal integration from stimulus to decision, using a reverse correlation protocol during psychophysics and simultaneous multiple-neuron / multiple-area recordings across MT and LIP, and interpreted via a generalized linear model. No empirical study has tested the hypothesized temporal integration of MT signals by LIP with direct measurement, which we will do by simultaneously recording from sets of MT and LIP neurons. Aim 2. Causal interrogation of this (putative) decision-making circuit, extending the MT-LIP framework described above to include reversible inactivations of one area, complemented by concurrent multiple-neuron recordings in the other area. The evidence linking LIP to decision-making has been almost entirely correlation. We propose to perform inactivations of the area to test for its causal or necessary role in the accumulation of evidence. Aim 3. Analysis of multiple stages of oculomotor decision-making, applying the multiple-neuron / multiple- area and inactivate-and-record approaches described in the aims above to LIP-FEF-PFC. Although the direct measurement of sensory signals in MT at the same time as LIP recording is likely to grant us significant new insights, the neural signals supporting motion discrimination almost certainly span a larger circuit with many sensory and cognitive stages. Here, we propose to apply the techniques described above to elucidate the relative roles of posterior parietal and prefrontal areas in decision-making.