Mechanisms of cognitive interference from value-based choice conflict

项目摘要(见说明)：检测和适应刺激-反应冲突是人类执行功能的关键和中心方面。然而，这种适应是如何发生的还不是很清楚。当多个刺激或同一刺激的多个方面与不同的行为反应相关时，就会发生冲突。在行为上，冲突导致反应更慢，错误更多。然而，观察家们显示出对冲突条件的时时刻刻适应。这种适应的结果是，随后的相互冲突的刺激对成绩的负面影响较小。已有理论认为，冲突反应中的自上而下控制采用选择性注意机制来减少额外的冲突；这种动态的内源性调节有望成为一种比经典实验设计更生态有效的模型来研究选择性注意。然而，现有的文献对这些冲突驱动的注意效应的性质并不一致。一些结果指出，冲突驱动的注意在视觉加工的早期阶段有多种机制。其他结果表明，某些注意机制，如分心抑制，可能不会在情境冲突驱动的注意力中发挥重要作用，这是有大量实验证据的。这些相同的数据不支持早期视觉加工中与冲突相关的注意效应。该项目建议使用功能磁共振成像和头皮脑电图来探索负责冲突适应的大脑机制，询问这些机制何时、何地以及如何影响视觉处理。具体地说，我们询问大脑是否以及如何使用选择性视觉注意来过滤掉不想要的信息来应对冲突，冲突驱动的知觉调制是否在基于特征和空间的处理上起作用，以及这种调制是否在预期即将到来的刺激事件时分配。

PROJECT SUMMARY (See instructions): Detection of and adaptation to stimulus-response conflict are critical and central aspects of human executive function. Yet, how such adaptation occurs is not well understood. Conflict occurs when multiple stimuli or multiple aspects of the same stimulus become associated with different behavioral responses. Behaviorally, conflict results in slower responses and increased errors. However, observers show moment-to-moment adaptation to conditions of conflict. An outcome of this adaptation is that subsequent conflicting stimuli have less of a negative impact on performance. It has been theorized that top-down control in response to conflict engages selective attention mechanisms to reduce additional conflict; this type of dynamic endogenous modulation has promise as a more ecologically valid model to study selective attention than classic experimental designs. However, the existing literature is inconsistent regarding the nature of these conflict driven attention effects. Some results point to multiple mechanisms of conflict driven attention operating at early stages of visual processing. Other results suggest that some attention mechanisms, such as distractor inhibition, for which there is substantial experimental evidence, may not play an important role in attention driven by contextual conflict. These same data do not support conflict related attention effects for early visual processing. This project proposes to use functional MRI and scalp electroencephalography to explore the brain mechanisms responsible for conflict adaptation, asking when, where and how these mechanisms affect visual processing. Specifically, we ask whether and how the brain uses selective visual attention to filter out unwanted information in response to conflict, whether conflict-driven perceptual modulation operates on feature and space based processing and whether such modulation is allocated in anticipation of impending stimulus events.