Mechanisms of cognitive interference from value-based choice conflict

项目总结（见说明）：发现和适应刺激-反应冲突是人类执行功能的关键和核心方面。然而，这种适应是如何发生的还不是很清楚。当多种刺激或同一刺激的多个方面与不同的行为反应相关联时，冲突就发生了。在行为上，冲突会导致反应变慢和错误增加。然而，观察员表现出对冲突条件的即时适应。这种适应的结果是，随后的冲突刺激对表现的负面影响较小。从理论上讲，对冲突的自上而下控制采用选择性注意机制来减少额外的冲突；这种类型的动态内源性调节有希望作为一个更生态有效的模型来研究选择性注意比经典的实验设计。然而，现有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，在视觉加工的早期阶段，冲突驱动的注意有多种机制。其他结果表明，一些注意机制，如干扰物抑制，可能在情境冲突驱动的注意中不起重要作用。这些相同的数据并不支持冲突相关的注意效应对早期视觉处理的影响。本项目拟利用功能性核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。具体而言，我们询问大脑是否以及如何使用选择性视觉注意来过滤冲突时不想要的信息，冲突驱动的感知调节是否在基于特征和空间的处理中起作用，以及这种调节是否在预期即将发生的刺激事件时分配。

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.