A key element of human flexible behavior concerns the ability to continuously predict and prepare for sudden changes in tasks or actions. Here, we tested whether people can dynamically modulate task preparation processes and decision-making strategies when the identity of a to-be-performed task becomes uncertain. To this end, we developed a new paradigm where participants need to prepare for one of nine tasks on each trial. Crucially, in some blocks, the task being prepared could suddenly shift to a different task after a longer cue-target interval, by changing either the stimulus category or categorization rule that defined the initial task. We found that participants were able to dynamically modulate task preparation in the face of this task uncertainty. A second experiment shows that these changes in behavior were not simply a function of decreasing task expectancy, but rather of increasing switch expectancy. Finally, in the third and fourth experiment, we demonstrate that these dynamic modulations can be applied in a compositional manner, depending on whether either only the stimulus category or categorization rule would be expected to change.

中文翻译：

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多任务环境中任务准备的动态变化：任务转换范式

人类灵活行为的一个关键要素涉及持续预测任务或行动的突然变化并为其做好准备的能力。在这里，我们测试了当要执行的任务的身份变得不确定时，人们是否可以动态调整任务准备过程和决策策略。为此，我们开发了一种新的范例，参与者需要为每次试验的九项任务之一做好准备。至关重要的是，在某些模块中，通过更改定义初始任务的刺激类别或分类规则，正在准备的任务可能会在较长的提示目标间隔后突然转变为不同的任务。我们发现，面对任务的不确定性，参与者能够动态调整任务准备。第二个实验表明，这些行为变化不仅仅是任务预期降低的结果，而是转换预期增加的结果。最后，在第三个和第四个实验中，我们证明这些动态调制可以以组合方式应用，具体取决于是否仅预期刺激类别或分类规则发生变化。