Decision making in action planning and control

现实世界中的动作任务涉及一系列决策过程，这些决策过程根据任务展开过程中提取的信息来确定下一步要做什么动作以及什么时候做。然而，关于动作控制和决策的研究在很大程度上是孤立发展的，直到最近，研究人员才开始研究它们之间的相互作用。这项研究的主要目的是通过研究人类目标导向任务背景下的决策过程，更好地了解大脑如何控制行动。这项研究由四个相互关联的项目组成。大多数关于到达的研究都集中在对单个目标的动作上，而在真实的世界中，我们经常面临多个潜在的行动目标。项目1的目的是研究大脑如何在目标不确定的条件下准备一个到达运动。最近的工作表明，在达到准备，大脑编码多个潜在的目标，并在指定目标之前发起的到达的初始方向，是有偏见的潜在目标的分布。这些结果是一致的想法，多个达到潜在目标的计划准备，但也是一致的概念，即在目标的不确定性的情况下，人们计划在一个战略方向上的一个单一的范围。许多自然任务涉及在每一步从备选方案中选择一系列目标，最优觅食理论提供了一个自然框架，用于研究与不同目标或目标序列相关的奖励和成本如何影响目标选择行为。虽然少数研究已经研究了价值和成本如何影响单个目标的选择，但据我们所知，没有研究调查过顺序目标选择。项目2将使用我们最近开发的运动觅食任务来研究与顺序目标选择相关的决策。人们经常面临是否值得投资学习一项新技能的决策，基于对与学习相关的成本和回报的评估。然而，据我们所知，这种决策与技能学习还没有定量研究。项目3将研究学习和奖励优化之间的相互作用，使用达到任务，参与者可以选择是否参与运动学习，这将最终使他们能够获得更高价值的奖励。一个关键的目标是评估参与者的能力，利用知识，他们自己的能力，学习新的技能，以作出良好的决定，是否投资于这样的学习。然而，没有研究已经检查，当观看涉及决策的行动任务，观察员提取潜在的有价值的信息，指导演员的选择。我们以前已经表明，观察者直接他们的目光到一个演员的运动的目标，只要他们可以预测的目标。在项目4中，我们将记录观察者的眼球运动，以测试他们是否学会预测一个演员的选择行为时，选择达到目标，这表明观察者可能会提取的值和成本，演员与目标相关联。

Real-world action tasks involve a sequence of decision-making processes that determine, based on information extracted during the unfolding task, which movement to make next and when to make it. However, research on movement control and decision-making has largely evolved in isolation, and it is only recently that researchers have begun to examine the interplay between them. The broad aim of the proposed research is to better understand how the brain controls action by investigating decision-making processes in the context of human target-directed reaching tasks. The proposed research consists of four interrelated projects.Whereas most studies of reaching have focused on movements made to single targets, in the real world we are often confronted with multiple potential targets of action. The aim of PROJECT 1 is to investigate how the brain prepared a reaching movement under these conditions of target uncertainty. Recent work has shown that during reach preparation, the brain encodes multiple potential targets and that the initial direction of reaches initiated before the target is specified, is biased by the distribution of potential targets. These results are consistent with the idea that multiple reach plans to potential target are prepared but are also consistent with the notion that, in cases of target uncertainty, people plan a single reach in a strategic direction. We will critically test between these alternatives.Many natural tasks involve choosing a sequence of targets from alternatives at each step and optimal foraging theory provides a natural framework for examining how rewards and costs associated with different targets, or target sequences, influence target choice behaviour. Although a handful of studies have examined how values and cost influence the selection of single targets, to our knowledge no study has investigated sequential target selection. PROJECT 2 will investigate decision-making related to sequential target selection using a movement foraging task that we have recently developed.People are frequently confronted with decisions about whether it is worthwhile investing in learning a new skill, based on an evaluation of the costs and rewards associated with learning. However, to our knowledge such decision-making related to skill learning has not been quantitatively studied. PROJECT 3 will investigate the interaction between learning and reward optimization using reaching tasks in which participants can choose whether to engage in motor learning, which will ultimately enable them to obtain higher value rewards. A key aim is to assess participants’ ability to use knowledge about their own ability to learn new skills to make good decisions about whether to invest in such learning.Studies of action-observation have shown that observers extract information about the actor’s goals. However, no research has examined whether, when watching action tasks involving decision-making, observers extract potentially valuable information that guides the actor’s choices. We have previously shown that observers direct their gaze to the target of an actor’s movement as soon as they can predict the target. In PROJECT 4, we will record observer’s eye movements to test whether they learn to predict an actor’s choice behaviour when selecting reach targets, suggesting the observer may extract the values and costs that the actor associates with the targets.