Priming of control: implicit contextual cuing of top-down attentional set.
Priming of control: implicit contextual cuing of top-down attentional set.
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DOI：
10.1523/jneurosci.0934-12.2012
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发表时间：
2012-06-13
期刊：
影响因子：
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通讯作者：
Egner T
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文献类型：
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作者：
King JA;Korb FM;Egner T
长期以来，认知模型一直在区分“自动”联想过程和“受控”联想过程，前者可以以自下而上的方式触发，后者内部目标以深思熟虑的、自上而下的方式指导信息处理。然而，最近的行为研究对这种二分法的有效性提出了质疑，表明内隐上下文线索可以以一种暗示特定的自上而下控制状态的联想触发的方式调节行为。在这里，我们利用功能性磁共振成像（fMRI）来测试这些行为发现是否真正反映了在线的、自下而上的、自上而下的注意力控制设置。使用侧侧干扰任务，刺激位置提示不一致试验的可能性，我们发现内隐的、情境特定的干扰解决改善的行为现象反映在内侧顶叶上小叶（mSPL）的血流动力学活动中，之前涉及自愿（而不是启动）注意力转移。此外，mSPL与处理侧侧刺激的视觉区域表现出情境特异性的功能耦合，后者的调节可预测行为效应。最后，这种情境控制的实施是“动态的”，也就是说，它是通过切换到与高冲突相关的情境而在线启动的。这些结果表明，自上而下的控制状态可以被绑定到情景事件表征中，并随后被这些表征的其他特征启动。总之，我们的发现说明了联想处理和控制处理之间比传统假设更密切的联系，并将这种联系的神经基质置于后顶叶皮层。
Cognitive models have long distinguished between “automatic” associative processes that can be triggered in a bottom-up fashion, and “controlled” processes, where internal goals guide information processing in a deliberate, top-down manner. However, recent behavioral studies have cast doubt on the validity of this dichotomy, showing that implicit contextual cues can modulate performance in a way suggestive of an associative triggering of specific top-down control states. Here, we harnessed functional magnetic resonance imaging (fMRI) in humans to test whether these behavioral findings truly reflect online, bottom-up priming of top-down attentional control settings. Using a flanker interference task where stimulus location cued the likelihood of incongruent trials, we found that the behavioral phenomenon of implicit, context-specific improvements in interference resolution was mirrored in hemodynamic activity in the medial superior parietal lobule (mSPL), previously implicated in voluntary (as opposed to primed) attention shifts. Moreover, the mSPL displayed context-specific functional coupling with visual regions involved in processing the flanker stimuli, and the modulation of the latter was predictive of the behavioral effects. Finally, the implementation of this contextual control was “on the fly”, that is, it was primed online by a switch to the context associated with high conflict. These results suggest that top-down control states can be bound into episodic event representations and can subsequently be primed by other features of those representations. Together, our findings illustrate a more intimate link between associative and controlled processing than is traditionally assumed, and place the neural substrate of that linkage in the posterior parietal cortex.