Department of Psychology and Center for Cognition, Learning, and Memory, University of Bern, Muesmattstr. 45, 3000, Bern 9, Switzerland.
Cogn Affect Behav Neurosci. 2013 Sep;13(3):575-83. doi: 10.3758/s13415-013-0160-z.
When bivalent stimuli (i.e., stimuli with relevant features for two different tasks) occur occasionally among univalent stimuli, performance is slowed on subsequent univalent stimuli even if they have no overlapping stimulus features. This finding has been labeled the bivalency effect. It indexes an adjustment of cognitive control, but the underlying mechanism is not well understood yet. The purpose of the present study was to shed light on this question, using event-related potentials. We used a paradigm requiring predictable alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The results revealed that the bivalency effect elicited a sustained parietal positivity and a frontal negativity, a neural signature that is typical for control processes implemented to resolve interference. We suggest that the bivalency effect reflects interference, which may be caused by episodic context binding.
当二价刺激（即具有两种不同任务相关特征的刺激）偶尔出现在单价刺激中时，即使后续的单价刺激没有重叠的刺激特征，它们的反应也会变慢。这一发现被称为二价效应。它反映了认知控制的调整，但目前尚不清楚其潜在机制。本研究的目的是利用事件相关电位来阐明这个问题。我们使用了一种需要在三个任务之间进行可预测交替的范式，其中二价刺激偶尔出现在一个任务中。结果表明，二价效应引发了持续的顶区正波和额区负波，这是一种典型的控制过程的神经特征，用于解决干扰。我们认为，二价效应反映了干扰，这种干扰可能是由情景语境绑定引起的。
