University of Trento, Italy.
J Cogn Neurosci. 2011 Oct;23(10):2838-51. doi: 10.1162/jocn.2011.21634. Epub 2011 Jan 25.
To assess whether working memory contents can effectively bias visual selection even when they do not represent the current target in the attention task, we recorded the ERP activity from participants performing both a memory task and, in the retention period, a visual search task. In this task, a distracter matching the memory content could be presented on the same side (congruent trials) or on the opposite side (incongruent trials) relative to the target location (Experiment 1 and Experiment 2). On some trials, only the matching distracter (but no target) was presented (catch trials, Experiment 2). Results showed that the N2pc component was modulated by the presence and location of a matching distracter. We interpret these results as evidence that the involuntary control exerted by the irrelevant memory contents coexists with the strategic mechanism related to the search target, influencing attention selection with roughly equal power. In Experiment 3, we found that the modulation of the N2pc is not strictly related to the active maintenance of the memory-target features but can also be elicited by repetition priming. Overall, these findings suggest that, together with the physical properties of the stimuli presented in the visual field, irrelevant memory contents represent a powerful class of factors that lead to involuntary attentional control.
为了评估工作记忆内容是否可以有效地影响视觉选择，即使它们在注意力任务中不代表当前目标，我们记录了参与者在执行记忆任务和在保留期执行视觉搜索任务时的 ERP 活动。在这个任务中，与记忆内容匹配的分心物可以在目标位置的同侧（一致试验）或对侧（不一致试验）呈现（实验 1 和实验 2）。在一些试验中，只有匹配的分心物（但没有目标）呈现（捕捉试验，实验 2）。结果表明，N2pc 成分受到匹配分心物的存在和位置的调节。我们将这些结果解释为证据，证明无关记忆内容的无意识控制与与搜索目标相关的策略机制共存，以大致相等的力量影响注意力选择。在实验 3 中，我们发现 N2pc 的调制与记忆-目标特征的主动保持并不严格相关，也可以通过重复启动来引发。总的来说，这些发现表明，与呈现于视野中的刺激的物理属性一起，无关的记忆内容代表了一类强大的因素，导致了无意识的注意力控制。
