NRSA: Dynamic evaluation and control of decision making

描述（由申请人提供）：我们建议研究感觉整合、假设检验和反应选择的基本人类决策机制。我们还建议研究必要的控制机制，以调节这些决策过程中，在不同的任务条件。我们建议使用事件相关脑电图（EEC）和功能磁共振成像（fMRI）来研究这些机制，以补充我们现有的行为结果。我们提出要解决的主要问题是，在非人类灵长类动物中，一个简单的“泄漏竞争累加器”（LCA）模型的神经回路下的感知决策是否在人类大脑中实现;如果是这样，是否存在证据证明我们对这个模型的扩展，可以解释与认知控制相关的表现适应性-这种干扰是大多数精神疾病的核心。一个简单的LCA模型的感觉整合和假设检验，支持直接的神经元记录在非人类灵长类动物表明，在外侧顶内沟（区LIP）的神经元实施的背景下，需要眼动反应的动作识别任务的证据加权过程。此外，这种活动受到与可能结果相关的预期奖励的调节。我们的假设是，这些现象反映了三个普遍的，跨物种的原则，在大多数任务中，所有的反应模式：1）刺激-反应协会是在大脑中实施的中间阶段的处理，转换的输出刺激识别阶段的反应启动; 2）在响应通道的这些初始阶段中的斜坡活动不仅反映了在响应之前对预期运动特征的预先准备，而且--关键的是--它反映了关于做出哪种反应的证据的实际权衡; 3）认知控制在其最简单的形式中在此阶段通过在连续的奖励和成本监控的基础上调节应用于此证据的阈值来实现。我们建议测试这一假设使用的动作识别任务，涉及两种反应方式和多种操纵的奖励应急。这项任务非常适合于将我们的非侵入性结果与直接记录数据相结合，我们开发的参与这项任务的电路模型允许对模型所有组件中激活的时间分布进行强有力的定量预测。这个任务可能提供了一个窗口，通过这个过程，由伤害或精神疾病引起的情感障碍通过不适当的阈值控制导致基本认知过程的障碍。它也可以解释控制缺陷如何导致奖励处理受损。

DESCRIPTION (provided by applicant): We propose to study basic human decision making mechanisms of sensory integration, hypothesis testing and response selection. We also propose to study the control mechanisms necessary for modulating these decision making processes in response to varying task conditions. We propose to investigate these mechanisms using event-related encephalography (EEC) and functional magnetic resonance imaging (fMRI) to complement our existing behavioral results. The major questions that we propose to address are whether a simple "leaky competing accumulator" (LCA) model of the neural circuitry underlying perceptual decision making in non-human primates is implemented in the human brain; and if so, whether evidence exists for an extension which we have developed of this model that can account for adaptations of performance associated with cognitive control -a disturbance of which is central to most forms of psychiatric disorder. A simple LCA model of sensory integration and hypothesis testing that is supported by direct neuronal recordings in non-human primates suggests that neurons in the lateral intraparietal sulcus (area LIP) implement an evidence-weighing process in the context of motion-discrimination tasks requiring eye-movement responses. Furthermore, this activity is modulated by the expected reward associated with possible outcomes. Our hypothesis is that these phenomena reflect three general, cross-species principles that govern all response modalities in most tasks: 1) stimulus-response associations are implemented in the brain at intermediate stages of processing that transform the outputs of stimulus identification stages into response initiation; 2) ramping activity in these initial stages of the response channels reflects not only the advance preparation of anticipated movement features prior to a response, but also - critically - it reflects the actual weighing of evidence about which response to make; 3) cognitive control in its simplest form is implemented at this stage by modulating the threshold applied to this evidence on the basis of continuous reward and cost monitoring. We propose to test this hypothesis using a motion-discrimination task involving two response modalities and multiple manipulations of reward contingency. This task is well suited for aligning our noninvasive results with direct recording data, and the model we have developed of circuits involved in this task allow strong, quantitative predictions about the temporal profile of activation in all of the model's components. This task may provide a window into the process by which disturbances of affect resulting from injury or psychiatric disease lead to disturbances of basic cognitive processing through inappropriate threshold control. It may also explain how control deficits lead to impaired reward processing.