Multiple memory systems for efficient temporal order memory

Abstract:

We report distinct contributions of multiple memory systems to the retrieval of the temporal order of events. The neural dynamics related to the retrieval of movie scenes revealed that recalling the temporal order of close events elevates hippocampal theta power, like that observed for recalling close spatial relationships. In contrast, recalling far events increases beta power in the orbitofrontal cortex, reflecting recall based on the overall movie structure.

Authors:

• Anna Jafarpour

• Jack J. Lin

• Robert T. Knight

• Elizabeth A. Buffalo

Date: 2023

DOI: https://doi.org/10.1002/hipo.23550

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Event segmentation reveals working memory forgetting rate

Abstract:

We encounter the world as a continuous flow and effortlessly segment sequences of events into episodes. This process of event segmentation engages working memory (WM) for tracking the flow of events and impacts subsequent memory accuracy. WM is limited in how much information (i.e., WM capacity) and for how long the information is retained (i.e., forgetting rate). In this study, across multiple tasks, we estimated participants’ WM capacity and forgetting rate in a dynamic context and evaluated their relationship to event segmentation. A Ushaped relationship across tasks shows that individuals who segmented the movie more finely or coarsely than the average have a faster WM forgetting rate. A separate task assessing long-term memory retrieval revealed that the coarse-segmenters have better recognition of temporal order of events compared to the fine-segmenters. These findings show that event segmentation employs dissociable memory strategies and correlates with how long information is retained in WM

Authors:

• Anna Jafarpour

• Elizabeth A. Buffalo

• Robert T. Knight

• Anne G.E. Collins

Date: 2022

DOI: https://doi.org/10.1016/j.isci.2022.103902

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