Mechanisms underlying flexible task choice: Understanding context and reward effects

在不断变化的环境中，目标导向的行为需要两种对立的控制模式之间的动态平衡：一方面，目标需要保持并不受干扰(稳定性)，另一方面，目标需要放松并在发生重大变化时灵活更新(灵活性)。为了考察任务选择的灵活调节，我们将使用自愿任务转换范式。在该项目的第一部分，我们将调查背景效应背后的机制，这描述了观察到，当人类处于频繁的被迫选择的背景下时，他们更频繁地自愿转换。该项目的第二部分将致力于以下问题：为什么当回报前景增加时，人类更频繁地切换到不同的任务；为什么当回报前景保持不变时，他们表现出更稳定的行为。为了回答这些问题，我们将依靠行为测量(任务选择、反应时间、错误率和主观努力成本)、斜视测量(测量努力和唤醒)和准备活动的电生理相关性。首要目标是加深我们对环境和动机如何影响灵活任务选择的理解。

Goal directed behavior in a constantly changing environment requires a dynamic balance between two antagonistic modes of control: on the one hand, goals need to be maintained and shielded from distraction (stability), and, on the other hand, goals need to be relaxed and flexibly updated whenever significant changes occur (flexibility). To investigate the flexible modulation of task choice, we will use the voluntary task switching paradigm. In the first part of the project, we will investigate the mechanisms underlying the context effect, which describes the observation that humans switch more often voluntarily when they are in a context of frequent forced choices. The second part of the project will be devoted to the question why humans switch more often to a different task when reward prospect increases and why they show more stable behavior when reward prospect remains unchanged. To answer these questions, we will rely on behavioral measures (task choice, reaction times, error rates, and subjective effort costs), pupillometry (to measure effort and arousal) and electrophysiological correlates of preparatory activity. The overarching goal is to deepen our understanding how context and motivation impact flexible task choice.