Visual Working Memory Modulates Attentional Orienting At Preattention Stage

Working memory (WM) and attention are regarded as two of the most important cognitive structures. WM includes many core cognitive processings such as information processing, temporary dynamic storing and executive control system. And attention is as a "gatekeeper" for external information accessing to information processing system. The interaction between the two processes is a central mechanism of information processing system.WM can be regarded as origin of the content of consciousness, and attention can be consider as controller of relevant information access to consciousness, so it is important to study the interaction between them.There were many studies found that when visual working memory (VWM) shared some features, the content of VWM would guide attention orienting in a flexible manner at attention stage. But visual attention includes two stages of processing: preattention stage with a limitless capacity and parallel processing, and attention stage with a limit capacity and serial processing (see Wolfe, 1998). A lots of researchers generally considered that attention orienting at preattention stage was automatic and involuntary, not be controlled by consciousness for many decades. But this view is be doubted in these years, many recent studies show that: even at preattention stage, attention orienting is not always automatic, it is modulated by working memory executive function (prefrontal cortex) in a top-to-down manner.Considering attention orienting is modulated by working memory executive system at preattention stage, there is another question whether the content of working memory can top-to-down guide attention orienting at preattention stage? What manner it can be? What differences of it from at attention stage? It is a very important question but few studies explored. The current research combining working memory task and feature-based visual search task, aims to explore how the content of VWM affects attentional orienting at preattention stage.Experiment 1 is a orientation-feature-based visual search task (that is the very visual search task used in experiment 2 and experiment 3), in order to explore weather this task is parallel search or not; Experiment 2 (including experiment 2a and experiment 2b) aims to find the effect of attentional orienting from VWM when the content of VWM may be the target of following parallel visual search (target-relevant condition); In experiment 3, we want to find how VWM affects attentional orienting when the content of VWM never be the target of following visual task (target-irrelevant condition).Here, we demonstrate, even at preattention stage, attentional orienting is top-down modulated by VWM. But compared with at attention stage, when the items kept in VWM related to the following visual search target, this item will guide attention to its location, slowed processing of target when this item is as distractor in visual array, and find no effect when this item is as target in visual array; but when the content of VWM is irrelevant to following search target, attention will ignore the distractor that matched the content of VWM, efficiently process the target.