Grouping Functionally-related Objects In Working Memory

Visual working memory(VWM)is a cognitive system of limited capacity that temporally stores and manipulates visual information.Researchers had carried out a series of researches on the storage capacity and storage mechanism,and had achieved fruitful results.However,only independent objects that did not have any relation between each other were used as stimuli in previous researches,and our visual system is designed to represent structured real world scenes rather than independent object.In recent years,a growing body of research found that objects are stored in VWM in relation with each other(such as Gestalt organization).The revealed relations that impact VWM are mostly based on low-level relations.The current study examined whether VWM could extract and make use of high-level relations such as functional relation,which are important for perceptual organization.It should be noted that objects with functional relations are both functionally related and interactive,and these two cues are both important to perceptual grouping.Current study includes three parts:the first part adopted change detection paradigm to repeat classic functional grouping effect.Eighteen real-world objects(Experiment 1a)and line drawings of common objects(Experiment lb)served as stimuli.The second part explored whether the functional relations between objects could be used to enhance working memory performance(Experiment 2a,2b);The third part moved one step forward to examine whether objects could be integrated inside VWM according to their functional relations(Experiment 3 a,3b).Results show that:(1)VWM could extract and make use of functional relation.(2)Functional grouping in VWM is different from the perceptual grouping effect that functionally related objects were not grouped when they are not interactive.The study shows that the organization in VWM could carry out in a more flexible manner than the perceptual organization,breaking the spatio-temporal constraints suffered in online perception.