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A fundamental question in comparative cognition concerns the evolution of consciousness. It is unlikely that consciousness appeared in humans without any precursors in other animals. Yet, the concepts that dominate our understanding of consciousness are inherently human centered, focusing on subjective experiences with a rich use of language. This understanding of consciousness is likely empirically intractable in studies of nonhumans. An alternative approach focuses on adopting a functional perspective. What function does consciousness serve? What can an animal capable of such a function do via its behavior? In this connection, I review the development of animal models of episodic memory. Episodic memory involves recalling the past and in humans is described as the phenomenological conscious experience of projecting oneself (autonoesis) in time (chronesthesia). Because there are no agreed upon empirical approaches to investigate subjective experiences in nonhumans, efforts to develop animal models of episodic memory have focused on the contents of episodic memory. I review experiments using rats that suggest that, at the moment of a memory assessment, the animal remembers back in time to an earlier event or episode. I conclude by evaluating implications of episodic memory in rats as a functional window into the evolution of consciousness.
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Temporal foundations of episodic memory
A fundamental question in the development of animal models of episodic memory concerns the role of temporal processes in episodic memory. Gallistel (1990) developed a framework in which animals remember specific features about an event, including the time of occurrence of the event and its location in space. Gallistel proposed that timing is based on a series of biological oscillators, spanning a wide range of periods. Accordingly, a snapshot of the phases of multiple oscillators provides a representation of the time of occurrence of the event. I review research on basic timing mechanisms that may support memory for times of occurrence. These studies suggest that animals use biological oscillators to represent time. Next, I describe recently developed animal models of episodic memory that highlight the importance of temporal representations in memory. One line of research suggests that an oscillator representation of time supports episodic memory. A second line of research highlights the flow of events in time in episodic memory. Investigations that integrate time and memory may advance the development of animal models of episodic memory.
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- Award ID(s):
- 1946039
- PAR ID:
- 10494117
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Learning & Behavior
- Volume:
- 52
- ISSN:
- 1543-4494
- Subject(s) / Keyword(s):
- Episodic memory animal models of episodic memory oscillator pacemaker accumulator time of occurrence short interval timing long interval timing rat
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3758/s13420-023-00608-x
