Shared structure facilitates working memory of multiple sequences

Abstract

Daily experiences often involve the processing of multiple sequences, such as speech processing and spatial navigation, yet storing them challenges the limited capacity of working memory (WM). To achieve efficient memory storage, relational structures shared by sequences would be leveraged to reorganize and compress information. Here, participants memorized a sequence of items with different colors and spatial locations and later reproduced the full color and location sequences, one after another. Crucially, we manipulated the consistency between location and color sequence trajectories. First, sequences with consistent trajectories demonstrate improved memory performance and a trajectory correlation between the reproduced color and location sequences. Interestingly, color sequence undergoes spontaneous forward neural replay when recalling trajectory-consistent location sequence. These results reveal that shared common structure is spontaneously leveraged to integrate and facilitate WM of multiple sequences through neural replay and imply a role of common cognitive map in efficient information organization in WM.