Free recall is shaped by inference and scaffolded by event structure

Area of Science:

• Cognitive Psychology
• Neuroscience
• Computational Modeling

Background:

• Human experience is continuous, yet perceived and remembered as discrete events.
• Event boundaries are theorized to enhance memory encoding for adjacent information.
• The precise impact of event boundaries on item-level memory, especially in dynamic settings, remains unclear.

Purpose of the Study:

• To investigate how event boundaries and rule uncertainty influence free recall of word stimuli.
• To examine the relationship between decision certainty and memory recall performance.
• To understand the role of event structure in shaping episodic memories.

Main Methods:

• A novel task was designed where participants recalled words grouped by hidden rules (events) with abrupt rule shifts creating boundaries.
• Free recall of word stimuli was analyzed for clustering based on event structure.
• A reinforcement-learning model was employed to quantify recall performance and decision certainty.

Main Results:

• Memory recall exhibited clustering, with words from the same event being recalled together.
• Contrary to predictions, recall for items immediately following an event boundary was impaired.
• A positive correlation was found between decision certainty and recall success.

Conclusions:

• Episodic memory is significantly influenced by the temporal structure of events and inferred event boundaries.
• The immediate post-boundary period represents a challenge for memory encoding.
• Decision certainty is a key factor modulating memory recall efficacy.