工作记忆表征的激活与抑制状态对注意引导效应的影响

Attentional Guidance from Activated and Inhibitory States of Working Memory Representations

本研究采用双任务范式,通过定向遗忘任务操纵工作记忆表征状态,分别在目标无关和目标相关条件下考察工作记忆激活与抑制状态对视觉搜索早期注意引导效应的影响。实验1与实验2发现当工作记忆表征只可能与视觉搜索分心物匹配时(目标无关条件),处于激活状态的工作记忆表征会引导视觉注意偏向到与之匹配的分心物,表现出注意引导效应,而处于抑制状态的工作记忆表征则没有观察到注意引导效应。实验3与实验4发现,当工作记忆表征有可能与视觉搜索目标匹配时(目标相关条件),处于激活状态的工作记忆表征能捕获注意,而处于抑制状态的工作记忆表征只有与视觉搜索目标匹配时,才表现出对该搜索目标反应的延迟。这些研究的结果表明(1)处于激活状态的工作记忆表征能有效地引导注意偏向到与之匹配的搜索目标或分心物,并且这种注意引导效应并未受到抑制动机的影响而被消除或反转;(2)处于抑制状态的工作记忆表征能将抑制状态传递到视觉搜索阶段,并延迟对与之匹配的搜索目标的反应。

Attention and working memory are two of the core cognitive processes in the human＇s information processing system. Working memory and visual attention are intimately related, and the contents of working memory can be referred as ＂activated＂ representations severed as ongoing cognition and action. In the meantime, working memory representations currently within the focus of attention can guide attentional selection and behavioral execution. In recent decades, a mount of studies have shown that the activated representations in working memory could top-down capture attention, even if the representations were irrelevant to the task goals, which displayed a robust working memory-driven guidance effect. However, whether the inhibitory representations in working memory can also guide attention, is still a controversial issue？ Here, in 4 experiments, the authors manipulated the states of working memory representations with the directed forgetting task, and attempted to explore the effect of activated and inhibitory states of working memory representations on working memory based attentional guidance respectively in task-irrelevant and task-relevant experimental situations. The participants in present study were asked to firstly perform a directed forgetting task, then to search for a target of circle among the distractors of squares, and finally to perform a memory test. In the directed forgetting task, the remember cue in experiment 1 and 3, and the forget cue in experiment 2 and 4 were used to respectively indicate the participants to remember or forget one of two colored squares already stored in working memory. The to-be-remembered （TBR） item and to-be-forgotten （TBF） item in working memory would reappear in visual search task and might match color with one of distractors only in experiment 1 and 2 （i.e., task-irrelevant situation）, and might match color with either the target or the distractor in experiment 3 and 4 （i.e., task-relevant situation）. In experiment 1 and 2, the results suggested that no matter what types of cues used in the directed forgetting task, when the distractor in visual search task matched color with TBR item, the TBR-matched distractor could capture more attention and slow down the visual search, displaying the attentional guidance effect. However, when the distractor matched the TBF item, neither attentional guidance effect nor attentional inhibition effect was observed. In experiment 3 and 4, the results for the TBR items showed that the visual search was accelerated under TBR-target matching condition and slowed down under TBR-distractor matching condition both in experiment 3 and 4, suggesting that the TBR item in working memory could guide attention biased to the TBR-matched items in visual search task. The results for the TBF items showed that when TBF item matched with distractor, there was no attentional guidance effect found both in experiment 3 and 4. When TBF item matched with target, the guidance effect was still not found in experiment 3. However, an attentional inhibitory effect which was opposed to the attentional guidance effect was observed in experiment 4, suggesting that the inhibitory state of the TBF item could postpone the response to the TBF-matched target. In conclusion, these results indicated that （1） the activated working memory representation could effectively guide attention bias both to the search target and to the distractor in visual search which matched features with such representation, and these attentional guidance effect could not be eliminated or reversed by the inhibitory motivation; （2） the inhibitory working memory representation could transfer the inhibitory state to the visual search task and postpone the response to the search target which matched the features with such representation.