Wildfire Response

Latest Videos

Video by Kevin D Schmidt

Chris Baldassano - Studying memory in the brain with the Method of Loci

Air Force Research Laboratory

Feb. 23, 2024 | 59:49

Description:
In this edition of QuEST, we will hear from Dr. Christopher Baldassano, who will be discussing his work on event memory and the Method of Loci technique.

Abstract:
Current models of human memory have been developed primarily based on experiments in which participants are asked to memorize lists of unrelated words or pictures. These models, however, are missing a primary feature of typical, realistic experiences: in the real world, episodic memories are layered on top of "cognitive maps" that capture our general knowledge about the structure of familiar environments. A dinnertime conversation with a friend, for example, could be situated within a spatial map, a social network, or a temporal "restaurant" script. In this project we describe an experimental paradigm that can serve as a testbed for investigating memory models that can strategically use cognitive maps. This novel approach makes use of a unique and understudied subject population of "memory experts" who have spent years or decades optimizing their ability to bind arbitrary information to an internal cognitive map. In a preliminary analysis of novice (n=25) and expert (n=5) users of the Method of Loci technique, fMRI brain imaging shows evidence for the creation of conjunctive codes during encoding that are reinstated during memory retrieval. Overall, this project provides a roadmap to advance the current state-of-the-art in theories of episodic memory and in fMRI experimental methods.

Key Moments and Questions in the video include:
Columbia University lab colleagues
Specializes in behavioral experiments using
Movies
Music
Stories & Poetry
Behavior
Computational Models
fMRI
Music as a continuous experience
Stories provide a structure overtime
Word lists used in memory studies do not relate to worldly experiences
How does the brain represent the temporal structure of realistic experiences?
Event perception
Schemas + scripts
Episodic memory
Predictive coding
Literature on event boundaries is still controversial
Different kinds of segmentation in the brain
How is prior knowledge used to build event representations?
Event schemas and scripts
Ambiguous stories/scripts
fMRI
Where are scripts activated?
Does script activation predict better detailed memory?
Can we strategically use a schema even in the absence of any schema in the stimulus?
Word lists strategy
Narrative techniques
Hypothesis: Given the constraints of human memory, the optimal strategy for encoding an arbitrary sequence is:
Pre-learned temporal script
General semantic knowledge creates meaningful bridges between item and locus
Schema activation impacts episodic memory
Better understanding of how memory athletes are engaging these systems
Testing the mind of a memory expert: Paul Mellor
Method of Loci
fMRI
Visual cortex
Decoding from early vision
Tracking locus activation
Major system
Idea: Study how the mental athletes attach memories to mental maps
Look at the brains of experts
Train people to use these techniques
Practice with loci
Measure brain activity for each locus
Measure brain activity during recall
Are some people more effective than others at memory mapping
How much conjunctive information is added when linking item to locus?
Models for cognition