The Effect Of Feature-based And Spatial Orienting Attention In Visual Working Memory Representation

During the retention phase of the paradigm of detected change in working memory,a cue is used as the retro-attention cues paradigm(retro-cue paradigm,that is,after the memory item appears for a period of time.A cue that direct to an item related to a memory item which can regulate the internal representation of visual working memory.The paradigm which has been used by researchers to identify the internal representation of visual working memory in the selection of directed attention.(Nobre,2003).The same paradigm is also used to examine whether feature-based retro-cues can also contribute to visual working memory internal representation to select the content.In addition,we investigated whether the allocation of attention to the items in VWM differ with respect to parallel access to adjacent and non-adjacent locations.To explore whether the mechanisms of feature-based and spatial attention are same.The two experiments are based on the on different kinds of types of retro-attention cues to test the efficacy of valid retro-cues.Especially the spatial type,which are consisted of two attention cues,one is the typical location-space clue,indicating two locations.The other is the symbolic clue of the digital space,which consists of two numbers,representing two positions.And two feature-based retro-cues: a color retro-cue(one color represents two items)and a shape retro-cue(the outline of the two items).The two cued items were presented at either non-adjacent or adjacent locations.In summary,the following conclusions are obtained.(1)Overall retro-cuing benefits,as compared to a non-cue condition,were observed for all retro-cue types.(2)Feature-based retro-cues yielded benefits for cued items presented at bothnon-adjacent and adjacent;Whereas patial retro-cues were only effective when the cued items had been presented at adjacent locations.These findings demonstrate that attention selection and updating in visual working memory(VWM)can operate on different types of information,which makes the limited system of visual working memory flexible and effective.The observation that the representations of items presented at non-adjacent locations could only be selected with feature-based retro-cues,which suggests that feature-based and spatial based attentional selection in VWM rely on different mechanisms.