Interdisciplinary studies of decision-making and motor planning

大脑是如何做出行动决定的？经典理论认为，我们首先处理感官信息以建立对世界的内部表征，然后决定做什么，最后计划并执行选定的行动。然而，最近的神经和行为数据提出了不同的假设。他们认为，当我们看世界时，我们大脑的某些部分会自动处理感官信息，并行地指定当前可能的几个动作。然后，这些行为的神经表征相互竞争，直到赢家出现并被执行。这种竞争受到来自高级认知区域的信息的影响，但它发生在感觉运动系统本身。换句话说，行为是世界呈现给我们的行动需求和机会之间的一场持续的战斗。 在我的实验室里，我通过多学科的方法研究这个广泛的假设，这种方法将各种实验技术与决策和感觉运动控制的神经机制的计算模型相结合。这些模型是通过数学方程来表达的，这些数学方程被实现为计算机程序，这些计算机程序模拟了广泛的神经生理学和行为现象，并生成可以通过实验测试的预测。然后，实验的结果可以用于进一步完善模型，闭合循环，创建一个实验和理论相结合的方法，为我的学员提供广泛的多学科经验。 这个NSERC申请要求资金支持这项计算工作连同相关的人体实验沿着。一个项目研究大脑如何随着信息的到来而做出决定。它涉及行为研究以及经颅磁刺激（TMS）和功能成像。第二个项目研究运动系统本身如何影响决策。它涉及行为和TMS研究。这两个项目都由计算模型指导，旨在为自愿行为背后的神经机制以及精神障碍中的缺陷提供新的见解。

How does the brain make decisions about actions? Classical theories suggest that we first process sensory information to build an internal representation of the world, then decide on what to do, and finally plan and execute the selected action. However, recent neural and behavioral data suggest a different hypothesis. They suggest that as we look at the world, parts of our brain automatically process the sensory information to specify, in parallel, several actions that are currently possible. Neural representations of these actions then compete against each other until a winner emerges and is executed. This competition is biased by information from higher cognitive regions, but it takes place within the sensorimotor system itself. In other words, behavior is a constant battle between the demands and opportunities for action which the world presents to us. In my laboratory, I investigate this broad hypothesis through a multidisciplinary approach that combines a variety of experimental techniques with computational models of the neural mechanisms of decision-making and sensorimotor control. These models are expressed through mathematical equations implemented as computer programs that simulate a wide range of neurophysiological and behavioral phenomena, and generate predictions that can be experimentally tested. The results of the experiments can then be used to further refine the models, closing the loop to create a combined experimental and theoretical approach which provides my trainees with broad multidisciplinary experience. This NSERC application requests funds to support this computational work along with associated human experiments. One project investigates how the brain makes decisions as information arrives over time. It involves behavioral studies as well as transcranial magnetic stimulation (TMS) and functional imaging. A second project investigates how the motor system can itself influence decisions. It involves behavioral and TMS studies. Both projects are guided by computational models and aimed to provide new insights into the neural mechanisms underlying voluntary behavior, as well as into the kinds of deficits seen in mental disorders.