The Influence Of Attention On Extrinsic Features Binding In Visual Working Memory

The real world contains various visual objects.To have a coherent experience of the real world,we have to bind different sources of information.The human brain combine constituent single features to a coherent object.This is referred to as the feature binding problem.It has been suggested that the feature binding has a very critical influence on cognitive process,such as visual working memory(VWM).According to the sources of information,intrinsic feature binding refers to the binding of surface features from various stimulus dimensions belong to the same item.In contrast,extrinsic feature binding refers to the binding of a feature of given item and the features of backgrouds.It has been found that distinctive mechanisms are involved in intrinsic and extrinsic feature binding.This suggests that binding of intrinsic object information should be easier,faster,and more automatic than the extrinsic feature binding.In other word,the binding of extrinsic features required more attentional resources and intentional processing.Over the numberous studies,it has been debated whether retaining bindings in VWM requires more attention than retaining constituent features,focusing on the binding of intrinsic features.It has been found that object-based attention resource underlies the mechanism of rehearsing intrinsic feature binding in VWM,but not space-based or domain-general attention resource.Nevertheless,no study so far has explored the role of attention resource in retaining extrinsic feature binding in VWM.It is unclear that the mechanism of rehearsing extrinsic feature binding.To test these issues,we adopted single test change-detect paradigm,during the maintenance phase of VWM,we inserted backward counting task(Experiment 1)an object-based feature report task(Experiment 2)or a secondary visual search task(Experiment 3),to consume the types of attention resource available for extrinsic feature binding,and to explored the influence of the types of attention resource on the maitenance of extrinsic feature binding.There are 3 experiments in the current study: In Experiment 1,we insert a backward counting to exhaust general attention resource during the maintenance phase of VWM,and explored the influence of genenral attention resource on the maintenance of extrinsic feature binding.It has been found that the maintenance of extrinsic feature binding was impaired as same degree as the constituent features.In Experiment 2,we insert an object-based feature report task to exhaust object-based attention resource during the maintenance phase of VWM,and explored the influence of object-based attention resource on the maintenance of extrinsic feature binding.It has been found that the maintenance of extrinsic feature binding was selectively impaired.In Experiment 3,we insert a visual search task to exhaust space-based attention resource during the maintenance phase of VWM,and explored the influence of space-based attention resource on the maintenance of extrinsic feature binding.It has been found that the maintenance of extrinsic feature binding was impaired more than constituent single features,also called selectively impaired.In summary,the findings from the present study mainly suggested the following conclusion: Compared with the maintenance of single feature,the maintenance of extrinsic feature binding in VWM requires more space-based attention and more object-based attention,but not executive attention.