Interdisciplinary studies of decision-making and motor planning

大多数心理学理论旨在理解人类认知的高级方面。例如，对决策的研究通常涉及我们如何做出抽象的选择，如选择职业或购买房屋。这些理论通常认为，决策是在认知系统内做出的，然后才被传递到运动系统，以执行所需的动作-一个感知，思考，然后行动的串行架构。然而，人类大脑是漫长进化历史的产物，在这段历史的大部分时间里，动物面临的挑战与抽象决策任务截然不同。特别是，动物生活中的大多数决定都是在实时、动态变化的环境中做出的，没有时间进行仔细的考虑，然后进行行动规划。我曾提出，为了在这种动态情境中做出有效的行为，大脑使用了一种并行架构，在这种架构中，可以同时指定多个潜在的行动，根据当前的感官信息选择一个，甚至在执行过程中，如果情况突然发生变化，其他选项也会被考虑在内。这就是所谓的“竞争假说”（affordance competition hypothesis）。我的研究计划旨在测试和进一步发展这个总体框架，我希望更新我的NSERC发现补助金，以支持这一奋进的三个具体方面。项目1的目标是确定不断变化的感官信息与不断增长的行动冲动和需要相结合的机制。它将进一步探讨我们最近提出的“紧迫性门控模型”使用人类行为研究。项目2将开发一个在灵长类前额叶、运动前区和运动皮层以及基底神经节中实现动作选择的分布式网络的计算模型。它将基于我们在实验室神经记录实验中收集的数据的新分析。我相信这种分析揭示了支配决策的动力系统的特性，我们可以将这些特性整合到皮质和皮质下决策系统的复杂而现实的数学模型中。项目3将启动一个新的实验范式，用于研究在已经进行的行动中做出决定的情况。这将涉及人类持续跟踪移动目标的研究，而新的目标偶尔会出现。虽然任务对受试者来说是连续的，但新的目标将以这样一种方式呈现，以测试经典的“决定然后行动”范式的具体预测。通过这种方式，我们将研究在静态实验室条件下发展的现有理论中，哪些理论可以推广到真实的世界中的行为。

Most psychological theories are aimed at understanding advanced aspects of human cognition. For example, studies of decision-making usually address how we make abstract choices such as selecting a career or buying a house. These often lead to theories suggesting that decisions are made within a cognitive system prior to being transmitted to the motor systems for executing the required movements – a serial architecture of sensing, thinking, and then acting. However, the human brain is the product of a long history of evolution, and during most of that history, animals were faced with challenges very different from those of abstract decision tasks. In particular, most decisions in animal life are made in a real-time, dynamically changing environment that does not allow time for careful deliberation followed by action planning. I have proposed that for effective behavior in such dynamic situations, the brain uses a parallel architecture in which multiple potential actions can be specified simultaneously, one selected on the basis of current sensory information, and even during its execution other options remain under consideration in case circumstances suddenly change. This is called the “affordance competition hypothesis”.***My research program is aimed at testing and further developing this general framework, and I hope to renew my NSERC Discovery Grant to support three specific aspects of that endeavor. Project 1 will aim to determine the mechanism by which changing sensory information is integrated with the growing urge and need to act. It will further explore our recently-proposed “urgency gating model” using human behavioral studies. Project 2 will develop a computational model of the distributed network implementing action selection in the primate prefrontal, premotor, and motor cortex, as well as the basal ganglia. It will be based on a novel analysis of data we have collected during neural recording experiments in my lab. I believe that this analysis reveals the properties of the dynamical system that governs decision-making, and that we can incorporate these properties into a sophisticated and realistic mathematical model of the cortical and subcortical decision-making system. Project 3 will launch a new experimental paradigm for studying situations in which decisions are made during already ongoing actions. This will involve studies in which humans continuously track a moving target while new targets occasionally present themselves. Although the task will appear continuous to the subjects, the new targets will be presented in such a way as to test specific predictions from classic decide-then-act paradigms. In this way, we will investigate which of our existing theories, developed in static laboratory situations, generalize to behavior in the real world.***