Evaluating evidence from animal models of episodic memory.
Open accessAbstract
A fundamental question in comparative cognition concerns the ability to remember back in time to an earlier event or episode. This ability is referred to as episodic memory. Whether nonhumans can be used to model human episodic memory has engendered much interest and debate for over 2 decades. The central hypothesis of an animal model of episodic memory is that, at the moment of the memory assessment, the animal remembers back in time to a specific earlier event or episode. I describe (a) an approach for evaluating evidence of episodic memory in animal models (b) what aspects of episodic memory are being modeled in animals (c) what standards ought to be applied to a candidate model of episodic memory in nonhumans (d) the first evidence of episodic memory in nonhumans, and (e) a brief overview of the diversity of approaches that are now available. The remainder of the article focuses on the development of a robust model of episodic memory in rats. Converging lines of evidence suggest that rats provide a good model for exploring episodic memory. This evidence includes studies that focus on (a) what-where-when memory (b) source memory (c) binding of episodic memories (d) memory of multiple Items in context using episodic memory (e) replay of episodic memories (f), recollection, and (g) answering an unexpected question after incidental encoding. In each of these domains, I describe evidence for episodic memory in the absence of nonepisodic judgments of familiarity. I end with some consideration of future directions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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When information is encoded incidentally and subsequently tested in an unexpected memory assessment, the transformation of this information into a preselected future action is impossible.
“By contrast, when information is encoded incidentally and subsequently tested in an unexpected memory assessment, the transformation of this information into a preselected future action is impossible [79,82,85,90]”
From Is episodic-like memory <i>like</i> episodic memory? (2024) · cites this paper as [85]
The effect of age was not apparent in the standard what-where-when task, leading authors to conclude that non-episodic solutions are possible in what-where-when tasks.
“Interestingly, this effect was not apparent in the standard what–where–when task, leading the authors to conclude that non-episodic solutions are possible in what–where–when tasks, as suggested by others [79,85].”
From Is episodic-like memory <i>like</i> episodic memory? (2024) · cites this paper as [85]
To access incidentally encoded information, an animal must recall a holistic representation of the episode, containing many details surrounding the event as well as the event narrative sequence, and subsequently replay, target and manipulate this information within the event representation.
“To access incidentally encoded information, an animal must recall a holistic representation of the episode, containing many details surrounding the event as well as the event narrative sequence, and subsequently replay, target and manipulate this information within the event representation [85,92,94,114].”
From Is episodic-like memory <i>like</i> episodic memory? (2024) · cites this paper as [85]
Human episodic memory encompasses a variety of cognitive structures and processes amalgamating into an episodic memory system, and each episodic-like memory paradigm targets a different aspect of this system.
“human episodic memory encompasses a variety of cognitive structures and processes amalgamating into an episodic memory system, and importantly each episodic-like memory paradigm targets a different aspect of this system [85,109].”
From Is episodic-like memory <i>like</i> episodic memory? (2024) · cites this paper as [85]
As in all available behavioural paradigms evidence of episodic-like memory is based on the exclusion of alternative, non-episodic test solutions, it is unlikely that any single methodology will provide an exhaustive conclusion.
“As in all the available behavioural paradigms evidence of episodic-like memory is based on the exclusion of alternative, non-episodic test solutions, it is unlikely that any single methodology will provide an exhaustive conclusion [85].”
From Is episodic-like memory <i>like</i> episodic memory? (2024) · cites this paper as [85]
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“Interestingly, this effect was not apparent in the standard what– where–when task, leading the authors to conclude that non-episodic solutions are possible in what–where–when tasks, as suggested by others [79,85].”
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- Authors
- Crystal, J. D.
- Corresponding author
- Crystal, Jonathon D.
- ORCID
- Crystal, Jonathon D.
- Venue
- Journal of Experimental Psychology: Animal Learning and Cognition
- Published
- 2021-07
- Volume
- 47
- Issue
- 3
- Pages
- 337-356
- ISSN
- 2329-8456 (ISSN-L)
- 2329-8464
- OpenAlex
- W3203152986
- Cited by
- 41
- References
- 0
- Citations by year
- 2026: 3 · 2025: 8 · 2024: 17 · 2023: 6 · 2022: 7
- FWCI
- 3.95
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Locations
- Journal of Experimental Psychology Animal Learning and Cognition (publishedVersion, other-oa)
- PubMed (publishedVersion)
- Funders
- National Science Foundation (NSF/BCS-1946039)
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory Processes and Influences
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Cognitive Functions and Memory
- Keywords
- episodic memory, animal models of memory, rats, comparative cognition, source memory, memory binding, memory replay, recollection, incidental encoding, familiarity judgments
- MeSH terms
- Animals, Cognition, Mental Recall, Recognition, Psychology, Models, Animal, Rats, Memory, Episodic
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