The cognitive mechanisms of state transformation during the multi-state maintenance of visual working memory

Visual working memory (VWM) system serves as a cornerstone for high-level cognition. The state-based models of working memory delineated a hierarchy of functional states. Memory representations in the passive state are robustly maintained while the active representations were effectively processed at the same time. The memory representations are dynamically transferred between the two states according to task demands; however, it was still unclear how the state transformation process implemented to achieve a perfect storage-dissociation. To explore the property of transformation process, we adopted a sequential presentation paradigm where two memory arrays were presented sequentially; that effectively directs memory items for retention in the two distinct states. We modulated the temporal context concerned with the state transformation process, presentation time of the second array and retention interval between memory arrays. These results indicated that state transformation reflected a consolidation process of memory representations from the active into the passive state; this transformation process is subject to cognitive control. Moreover, we found that sufficient temporal context facilitated a smooth state transformation, thus minimizing the memory loss. These findings lead to a further understanding for the storage mechanism of working memory representations during the dynamic processing.