The Role Of Working Memory On Event Segmentation

Official URL: https://risc01.sabanciuniv.edu/record=b3403589

Event segmentation is known as the process of mentally partitioning continuous episodic events into meaningful units. It allows related information, that is grouped into an event, to be recalled better compared to information across different events. However, the role of working memory (WM) in this process remains relatively unexplored. Based on existing studies, we collected contrasting views about the role of WM on segmentation under two accounts: Accumulation, where memoranda are claimed to be accumulated until an event boundary, and Reactivation, where each memorandum is claimed to be transferred to Long-Term Memory (LTM) and is reactivated once there is an event boundary. Here, we challenged these accounts in a single EEG study, using a direct measure of WM capacity, Contralateral Delay Activity (CDA), and a sensitive measure of attentional involvement, Bilateral Alpha Power. We have found a significant systematic increase in CDA within main events, which supports the Accumulation account by reflecting the increase in WM capacity throughout memoranda within a main event. We also found a higher bilateral alpha suppression during the beginning of boundary events compared to the beginning of main events, which reflects the increased activation of WM representations, endorsing the claims of the Reactivation account. Our findings suggest that these claims do not have to be mutually exclusive. By co-existing, they may reflect the dynamic nature of the relationship between WM and event segmentation, expanding the scope of research on cognitive psychology.