Structure and function of declarative and nondeclarative memory systems
Open accessAbstract
This article reviews recent studies of memory systems in humans and nonhuman primates. Three major conclusions from recent work are that (i) the capacity for nondeclarative (nonconscious) learning can now be studied in a broad array of tasks that assess classification learning, perceptuomotor skill learning, artificial grammar learning, and prototype abstraction; (ii) cortical areas adjacent to the hippocampal formation, including entorhinal, perirhinal, and parahippocampal cortices, are an essential part of the medial temporal lobe memory system that supports declarative (conscious) memory; and (iii) in humans, bilateral damage limited to the hippocampal formation is nevertheless sufficient to produce severe anterograde amnesia and temporally graded retrograde amnesia covering as much as 25 years.
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Neither the race model nor CMPL theory incorporates procedural knowledge in their learning mechanisms, because episodic memory is a type of declarative memory.
“Note that neither the race model nor the CMPL theory incorporates procedural knowledge (or memory) in their learning mechanisms, as episodic memory (storing instances) is a type of declarative memory (Squire & Zola, 1996).”
From Testing the three-stage model of second language skill acquisition (2025) · cites this paper as Squire & Zola, 1996
Declarative and nondeclarative memory systems are distinguished depending on the critical involvement of medial temporal lobe regions, particularly the hippocampus, in the acquisition of memory.
“In neuropsychology, declarative and nondeclarative memory systems are distinguished depending on the critical involvement of medial temporal lobe regions, particularly of the hippocampus, in the acquisition of memory (1134).”
From About Sleep's Role in Memory (2013) · cites this paper as [1134]
Nondeclarative memories can be acquired without involvement of medial temporal lobe structures.
“In contrast to declarative memories, nondeclarative memories can be acquired without involvement of medial temporal lobe structures (1134).”
From About Sleep's Role in Memory (2013) · cites this paper as [1134]
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“Note that neither the race model nor the CMPL theory incorporates procedural knowledge (or memory) in their learning mechanisms, as episodic memory (storing instances) is a type of declarative memory (Squire & Zola, 1996).”
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“According to Squire and Zola (1996), this system is involuntary and consists of procedural memory for motor skills and habits, associative and non-associative learning driven by environmental conditioning, and priming, which improves information recognition based on previous exposure.”
- Authors
- Squire, L. R., & Zola, S. M.
- Affiliations
- University of California San Diego (US)
- Veterans Health Administration (US)
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 1996-11-26
- Volume
- 93
- Issue
- 24
- Pages
- 13515-13522
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC33639
- OpenAlex
- W2019044369
- Cited by
- 1,327
- References
- 3
- Citations by year
- 2026: 19 · 2025: 32 · 2024: 40 · 2023: 40 · 2022: 40 · 2021: 40 · 2020: 75 · 2019: 53 · 2018: 52 · 2017: 54 · 2016: 40 · 2015: 46 · 2014: 57 · 2013: 80 · 2012: 66
- FWCI
- 2.76
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (5r01ns019063-12)
- National Institute of Mental Health (R37MH024600, R01MH024600, MH24600)
- National Institute of Neurological Disorders and Stroke (NS19063)
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory Processes and Influences
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Cognitive Functions and Memory
- Keywords
- declarative memory, implicit memory, classification learning, artificial grammar learning, hippocampal formation, entorhinal cortex, perirhinal cortex, parahippocampal cortex, medial temporal lobe, anterograde amnesia, retrograde amnesia, non-human primates
- MeSH terms
- Amnesia, Amnesia, Retrograde, Animals, Haplorhini, Brain, Hippocampus, Humans, Learning, Memory, Models, Neurological, Models, Psychological, Primates, Temporal Lobe
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