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Evidence record

What is a memory made of?

Every sentence on the exploration belongs to at least one claim below. Each says what kind of statement it is, what it rests on, what the evidence does not establish, and how far it was checked. Nothing here is a score, and none of it is a verdict on a belief or a theory.

Last checked 24 September 2026.

  • Partly checked: 14
  • Source checked: 31
  • Presented as open: 5
  • A judgement, not a fact: 6

If something here is wrong, misquoted, out of date or unfair, write to support@unknownoceans.com and give the claim number, which does not change.

What the question takes for granted

A scientific question about what a memory physically is. The page separates what rodent experiments have shown, what is argued in people, and what no one has an account of.

  • A memory is a physical thing that can be located

    Contested

    Engram studies locate parts of specific memories in populations of cells in mice, and the same review describes a memory as spread across many regions. Whether that adds up to a thing with a place is what the page asks.

  • Remembering is reconstruction rather than playback

    Established

    Established for episodic memory in people: recall can be altered by questions and suggestion. How far this reaches, and the mechanism, are argued.

  • Memory is one faculty

    Contested

    The page argues against it: since H.M., memory for facts and events and memory for skills are held to depend on different systems.

How the question is labelled

Claim: Memory

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: Memory

Kind
Framing. Signposting. It asserts nothing a source could check.

The question

Claim: Remembering is not retrieval. It is closer to rebuilding.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

The page’s one-line version of the constructive view of episodic memory.

What this does not establish

Read as an abstract only. The constructive view is about episodic memory; it does not say that nothing is retrieved.

Claim 3 · checked 24 September 2026 · AI-assisted audit

Claim: We can now locate and artificially reactivate specific memories in mice.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: artificially reactivating a subset of hippocampal dentate gyrus neurons that were active during a fearful experience (and, therefore, part of a putative engram) induced memory retrieval in the absence of external retrieval cues (gain of function)

  • Supports

    Memory engrams: Recalling the past and imagining the futureIntroduction, scope

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: The discussion here is limited primarily to rodent experiments examining memory of an explicit experience that probe memory at the level of an engram.

What this does not establish

In mice. Nothing like it has been done in people.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Claim 4 · checked 24 September 2026 · AI-assisted audit

Claim: We still cannot say what a memory is in a way that explains why yours can change when you use them.

Kind
Open question. Something the page says is not known.
Review
Presented as open. The page says this is unresolved, and the review found that it is.

The review describes the engram as only beginning to be defined, and the reconsolidation account of change at recall is contested in people (claim 26).

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Outlook

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: The findings from many labs are beginning to define an engram as the basic unit of memory. However, many questions remain.

  • Qualifies

    Human memory reconsolidation: a guiding framework and critical review of the evidenceabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: Reconsolidation remains a viable but hotly contested explanation for some observed changes in memory expression in both humans and animals.

Corrected

24 September 2026. Previously: “explains why yours change every time you use them.” "Every time" overstated what reconsolidation research shows: in people the evidence is mixed, and in rats the effect depends on conditions.

Claim 5 · checked 24 September 2026 · AI-assisted audit

Claim: A memory feels like a recording. You had an experience, it was stored, and now you are playing it back.

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: Almost everything in that description is wrong,

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s judgement, following from the sections below: memory is several systems, can be changed at recall, and is reconstructed.

Claim 7 · checked 24 September 2026 · AI-assisted audit

Claim: and the parts that are wrong were established experimentally decades ago.

Kind
Historical claim. A statement about the past that historical evidence can test.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Loss of recent memory after bilateral hippocampal lesionsp. 16, Case 1, H. M.

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Case report

    The source reads: On September 1, 1953, bilateral medial temporal-lobe resection was carried out

  • Supports

    Reconstruction of automobile destructionExperiment I, Method, and Table 10-1

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: Forty-five students participated in groups of various sizes. Seven films were shown, each depicting a traffic accident. ... Smashed 40.8; Collided 39.3; Bumped 38.1; Hit 34.0; Contacted 31.8.

  • Context

    Fear memories require protein synthesis in the amygdala for reconsolidation after retrievalabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Experiment

    The source reads: consolidated fear memories, when reactivated during retrieval, return to a labile state in which infusion of anisomycin shortly after memory reactivation produces amnesia on later tests, regardless of whether reactivation was performed 1 or 14 days after conditioning

    Dated 2000 by its record.

What this does not establish

The reconsolidation result is from 2000 and in rats; its extension to people is contested (claim 26).

Claim 8 · checked 24 September 2026 · AI-assisted audit

What experiment has pinned down

Claim: What experiment has pinned down

Kind
Framing. Signposting. It asserts nothing a source could check.

Memory is not one system

Claim: Memory is not one system

Kind
What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, last paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: The starting point for these developments was the early discovery that motor skill learning was preserved in H.M. This finding revealed that memory is not a single faculty of the mind and led ultimately to the identification of the multiple memory systems of the mammalian brain.

Later work looked for

Europe PMC, 2009 on, "multiple memory systems": nothing found that abandons the declarative and nondeclarative distinction; how episodic and semantic memory divide is argued and the page no longer states it.

Claim 10 · checked 24 September 2026 · AI-assisted audit

Claim: The patient known as H.M., after bilateral removal of the medial temporal lobes in 1953, could no longer form new conscious memories of events.

Kind
Historical claim. A statement about the past that historical evidence can test.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Loss of recent memory after bilateral hippocampal lesionsp. 16, Case 1, H. M.

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Case report

    The source reads: On September 1, 1953, bilateral medial temporal-lobe resection was carried out

  • Supports

    Loss of recent memory after bilateral hippocampal lesionsp. 17, Case 1, summary

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Case report

    The source reads: this patient appears to have a complete loss of memory for events subsequent to bilateral medial temporal-lobe resection 19 months before

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, second paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: Declarative memory is what is meant when the term “memory” is used in everyday language, i.e., conscious knowledge of facts and events.

  • Qualifies

    The legacy of patient H.M. for neuroscienceConclusion

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: It is now clear that his memory impairment was not absolute and that he was able to acquire significant new knowledge

What this does not establish

The resection removed the medial parts of both temporal lobes, not the whole lobes. Later testing found his impairment was not absolute: he acquired some new knowledge over the decades.

Claim 11 · checked 24 September 2026 · AI-assisted audit

Claim: The operation left his existing technical skills intact,

Kind
Historical claim. A statement about the past that historical evidence can test.
Review
Source checked. The cited passage was read, and it says this.

What this does not establish

The summary covers all the patients in the paper, H.M. among them.

Claim 12 · checked 24 September 2026 · AI-assisted audit

Claim: and in 1962 Brenda Milner found he could still learn a new one: he learned to trace a star seen only in a mirror and kept the skill across three days, yet at the end had no recollection of having done the task before.

Kind
Historical claim. A statement about the past that historical evidence can test.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, first paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: Brenda Milner tested his ability to acquire a visuomotor skill (Milner, 1962)

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, first paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026

    The source reads: H.M. was shown a five-pointed star, with a double contour, and asked to trace its outline with a pencil, but in a condition when he could only see his hand and the star as reflected in a mirror.

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, first paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: H.M. acquired this mirror-drawing skill during ten trials and exhibited excellent retention across 3 days. Yet at the end of testing, he had no recollection of having done the task before.

What this does not establish

Rests on Squire’s account of Milner’s experiment.

Corrected

24 September 2026. Previously: “and the acquisition of new motor skill after that surgery became a study of its own, which is where the dissociation was established.” The only citation was Corkin 1968, which could be read only as a Crossref record and so carried nothing. Squire 2009 dates the first demonstration to Milner 1962 and describes it; the page now reports that, and Corkin 1968 is no longer cited.

Claim 13 · checked 24 September 2026 · AI-assisted audit

Claim: That dissociation opened the modern study of memory as several systems rather than one:

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, last paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: The starting point for these developments was the early discovery that motor skill learning was preserved in H.M. This finding revealed that memory is not a single faculty of the mind and led ultimately to the identification of the multiple memory systems of the mammalian brain.

Claim 14 · checked 24 September 2026 · AI-assisted audit

Claim: conscious memory for facts and events depends on the medial temporal lobe, while skills, habits and simple conditioning depend on other structures.

Kind
What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, last paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: declarative memory refers to the kind of memory that is impaired in H.M. and is dependent on the medial temporal lobe

  • Supports

    The legacy of patient H.M. for neuroscienceMultiple Memory Systems, last paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: These include systems that support skill learning, habit learning, simple conditioning, emotional learning, as well as priming and perceptual learning. The structures with special importance for these kinds of memory include the basal ganglia, the cerebellum, the amygdala, and the neocortex.

What this does not establish

A review by the researcher most associated with the framework. The taxonomy is broadly shared; how finely memory divides beyond it is argued.

Later work looked for

Europe PMC, 2009 on, "multiple memory systems": nothing found that abandons the declarative and nondeclarative distinction; how episodic and semantic memory divide is argued and the page no longer states it.

Corrected

24 September 2026. Previously: “That dissociation is the foundation of modern memory research: episodic memory, semantic knowledge, and procedural skill are physically different systems that fail independently.” The cited work separates declarative memory (facts and events together) from skills and other nondeclarative memory. It does not show episodic and semantic memory as physically separate systems that fail independently, which is argued; the sentence now says what the source says.

Claim 15 · checked 24 September 2026 · AI-assisted audit

Specific memories have physical traces that can be manipulated

Claim: Specific memories have physical traces that can be manipulated

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureGain-of-function studies

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: photo-stimulation of tagged engram cells was sufficient to induce freezing ... even though mice had never been shocked in this nontraining context

  • Supports

    Memory engrams: Recalling the past and imagining the futureLoss-of-function studies

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Subsequent studies using diverse methods to permanently or reversibly inactivate allocated or tagged neurons across several brain areas hypothesized to be part of an engram, in many memory tasks, produced comparable results

What this does not establish

In rodents.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Claim 16 · checked 24 September 2026 · AI-assisted audit

Claim: Neurons active during an experience can be genetically tagged and later artificially reactivated.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: artificially reactivating a subset of hippocampal dentate gyrus neurons that were active during a fearful experience (and, therefore, part of a putative engram) induced memory retrieval in the absence of external retrieval cues (gain of function)

What this does not establish

In mice.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Claim 17 · checked 24 September 2026 · AI-assisted audit

Claim: Doing so makes a mouse behave as though it is recalling that experience, in a place where the experience never happened.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureGain-of-function studies

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: photo-stimulation of tagged engram cells was sufficient to induce freezing ... even though mice had never been shocked in this nontraining context

What this does not establish

The behaviour measured is freezing, the conditioned fear response.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Claim 18 · checked 24 September 2026 · AI-assisted audit

Claim: The same techniques can suppress a specific memory or attach a false one.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureLoss-of-function studies

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Subsequent studies using diverse methods to permanently or reversibly inactivate allocated or tagged neurons across several brain areas hypothesized to be part of an engram, in many memory tasks, produced comparable results

  • Supports

    Memory engrams: Recalling the past and imagining the futureMimicry experiments

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Synchronous optogenetic activation of these ensembles while mice were in the homecage was sufficient to induce a false memory

What this does not establish

In mice, for simple conditioned memories such as fear of a context.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Claim 19 · checked 24 September 2026 · AI-assisted audit

Claim: Nearly all of it is rodent work.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureIntroduction, scope

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: The discussion here is limited primarily to rodent experiments examining memory of an explicit experience that probe memory at the level of an engram.

  • Qualifies

    Memory engrams: Recalling the past and imagining the futureIntroduction, scope

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Memory traces, or at least physiological correlates of memory, have been examined in invertebrate species, such as flies (23–27), octopus (28, 29), Aplysia sea slugs (30, 31), honey bee (32), and Hermissenda sea slugs (33).

    The review limits itself “primarily” to rodents and cites work in invertebrates, so the rodent work is nearly all of it rather than all.

What this does not establish

None of the tagging and reactivation experiments described here was done in people.

Corrected

24 September 2026. Previously: “All of it is rodent work.” A universal the source does not make: the Josselyn and Tonegawa review limits itself primarily to rodent experiments and cites engram work in flies and other invertebrates.

Claim 20 · checked 24 September 2026 · AI-assisted audit

Claim: This is as close as neuroscience has come to holding a memory in its hand.

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s judgement of claims 17 to 19; the review itself says the work is beginning to define the engram and that many questions remain.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Outlook

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: The findings from many labs are beginning to define an engram as the basic unit of memory. However, many questions remain.

Claim 21 · checked 24 September 2026 · AI-assisted audit

Recalling a memory can make it unstable

Claim: Recalling a memory can make it unstable

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

What this does not establish

Shown in rats; contested in people (claim 26). The Nature paper was read as an abstract only.

Later work looked for

Europe PMC, 2019 on, reconsolidation reviews: reviews of propranolol and of prediction error as a boundary condition, and Elsey and others 2018 on human studies, contested in people; the rodent result stands. Page qualified.

Corrected

24 September 2026. Previously: “Recalling a memory makes it unstable” Stated as a general law; the cited result is in rats under particular conditions, and the human evidence is contested.

Claim 22 · checked 24 September 2026 · AI-assisted audit

Claim: Retrieving a consolidated fear memory returns it, in rats, to a labile state in which it must be rebuilt to persist.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

What this does not establish

Read as an abstract. Auditory fear conditioning in male rats.

Later work looked for

Europe PMC, 2019 on, reconsolidation reviews: reviews of propranolol and of prediction error as a boundary condition, and Elsey and others 2018 on human studies, contested in people; the rodent result stands. Page qualified.

Corrected

24 September 2026. Previously: “Retrieving a consolidated memory returns it to a labile state” The result is for fear memories in rats; the sentence did not say either.

Claim 23 · checked 24 September 2026 · AI-assisted audit

Claim: Blocking protein synthesis in the amygdala during that window produces amnesia on later tests, whether the memory was a day old or a fortnight.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    Fear memories require protein synthesis in the amygdala for reconsolidation after retrievalabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in animals · Experiment

    The source reads: consolidated fear memories, when reactivated during retrieval, return to a labile state in which infusion of anisomycin shortly after memory reactivation produces amnesia on later tests, regardless of whether reactivation was performed 1 or 14 days after conditioning

  • Supports

    Fear memories require protein synthesis in the amygdala for reconsolidation after retrievalabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026

    The source reads: The lateral and basal nuclei of the amygdala (LBA) are believed to be a site of memory storage in fear learning. Infusion of the protein synthesis inhibitor anisomycin into the LBA shortly after training prevents consolidation of fear memories.

What this does not establish

Read as an abstract. Whether the trace is erased or only made unreachable is not settled by a behavioural test.

Later work looked for

Europe PMC, 2019 on, reconsolidation reviews: reviews of propranolol and of prediction error as a boundary condition, and Elsey and others 2018 on human studies, contested in people; the rodent result stands. Page qualified.

Corrected

24 September 2026. Previously: “leaves rats with no fear response on later tests” The abstract reports amnesia; "no fear response" claimed a completeness the readable source does not state.

Claim 24 · checked 24 September 2026 · AI-assisted audit

Claim: In rats, at least, remembering something can change it.

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s summary of claims 23 and 24.

Corrected

24 September 2026. Previously: “Remembering something changes it.” Generalised a rat result to all remembering.

Claim 25 · checked 24 September 2026 · AI-assisted audit

Claim: Whether the same happens in people is argued: a 2018 review of the human studies finds much that is consistent with it, and too many inconsistent results and rival explanations to conclude it.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

What this does not establish

Read as an abstract only.

Later work looked for

Europe PMC, 2019 on, reconsolidation reviews: reviews of propranolol and of prediction error as a boundary condition, and Elsey and others 2018 on human studies, contested in people; the rodent result stands. Page qualified.

Corrected

24 September 2026. Previously: “” Added. A critical review of human reconsolidation studies says the evidence cannot yet establish it in people, and the section sat under "known".

Claim 26 · checked 24 September 2026 · AI-assisted audit

Human memory is reconstructive and suggestible

Claim: Human memory is reconstructive and suggestible

Kind
What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    The cognitive neuroscience of constructive memory: remembering the past and imagining the futureabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: Episodic memory is widely conceived as a fundamentally constructive, rather than reproductive, process that is prone to various kinds of errors and illusions.

  • Supports

    Reconstruction of automobile destructionExperiment II, Method, Results and Table 10-2

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: One week later, the subjects returned ... There was no broken glass in the accident ... Yes: Smashed 16, Hit 7, Control 6.

What this does not establish

The field-level source was read as an abstract.

Later work looked for

Europe PMC, "Loftus Palmer replication": nothing found by title that overturns the result; the misinformation effect remains standard.

Claim 27 · checked 24 September 2026 · AI-assisted audit

Claim: Changing a single word in a question about a filmed crash (“smashed” versus “hit”) raises the speed witnesses report,

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Reconstruction of automobile destructionExperiment I, Method, and Table 10-1

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: Forty-five students participated in groups of various sizes. Seven films were shown, each depicting a traffic accident. ... Smashed 40.8; Collided 39.3; Bumped 38.1; Hit 34.0; Contacted 31.8.

What this does not establish

Experiment I: 45 students and seven films, mean estimates of 40.8 mph for "smashed" against 34.0 for "hit". The witnesses were students watching films.

Later work looked for

Europe PMC, "Loftus Palmer replication": nothing found by title that overturns the result; the misinformation effect remains standard.

Claim 28 · checked 24 September 2026 · AI-assisted audit

Claim: and a week later it more than doubles the number who say they saw broken glass that was never in the film.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Reconstruction of automobile destructionExperiment II, Method, Results and Table 10-2

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: One week later, the subjects returned ... There was no broken glass in the accident ... Yes: Smashed 16, Hit 7, Control 6.

    Of 50 in each group: 16 against 7 is 2.3 times, which is more than double.

What this does not establish

Experiment II: 16 of 50 said yes after "smashed", 7 of 50 after "hit" and 6 of 50 controls. A yes or no answer, not a detailed recollection.

Later work looked for

Europe PMC, "Loftus Palmer replication": nothing found by title that overturns the result; the misinformation effect remains standard.

Claim 29 · checked 24 September 2026 · AI-assisted audit

Claim: Suggest a childhood event that never happened, with a relative’s account behind it, and in a 2023 replication about a third of people were coded as remembering it.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    Lost in the mall again: a preregistered replication and extension of Loftus and Pickrell (1995)abstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Experiment

    The source reads: based on information provided by an older relative. We replicated the findings of the original study, coding 35% of participants as reporting a false memory for getting lost in a mall in childhood (compared to 25% in the original study).

    35 per cent of participants is within two points of a third (33.3).

  • Supports

    Creating memories for false autobiographical events in childhood: a systematic reviewSummary

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: In memory implantation studies, some recollective experience for the suggested events is induced on average in 47% of participants, but only in 15% are these experiences likely to be rated as full memories.

What this does not establish

Read as an abstract. 123 participants; the 35 per cent is the researchers’ coding of interviews, and how such reports should be coded is itself argued (claim 31).

Later work looked for

Europe PMC and Crossref, 2016 on, false memory implantation: Scoboria and others 2017 (mega-analysis, abstract) classify 30.4 per cent as false memories; Brewin and Andrews 2017 argue the rate of full memories is at most about 15 per cent; Murphy and others 2023 replicate at 35 per cent. Page now reports the dispute.

Corrected

24 September 2026. Previously: “Suggest a childhood event that never happened and about a third of people come to report remembering it.” The figure is one study’s coding, with the suggestion backed by a relative; stated as a general rate it overstated it.

Claim 30 · checked 24 September 2026 · AI-assisted audit

Claim: How many of those amount to a full memory is argued: a systematic review of such studies puts it at about 15 per cent at most.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

What this does not establish

The review predates the 2023 replication. Scoboria and others 2017, pooling eight studies, classified 30.4 per cent as false memories.

Other readings

Scoboria and others (2017) and Murphy and others (2023) code about a third as false memories; Brewin and Andrews argue for stricter criteria and participants’ own ratings.

Later work looked for

Europe PMC and Crossref, 2016 on, false memory implantation: Scoboria and others 2017 (mega-analysis, abstract) classify 30.4 per cent as false memories; Brewin and Andrews 2017 argue the rate of full memories is at most about 15 per cent; Murphy and others 2023 replicate at 35 per cent. Page now reports the dispute.

Corrected

24 September 2026. Previously: “” Added. The rate depends on how a report is coded, and a systematic review argues the rate of full memories is much lower than the headline figure.

Claim 31 · checked 24 September 2026 · AI-assisted audit

Where the account thins out

Claim: Where the account thins out

Kind
Framing. Signposting. It asserts nothing a source could check.

What the trace physically consists of

Claim: What the trace physically consists of

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: The dominant account places memory in patterns of synaptic strength across populations of neurons.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureThe “enduring changes” of an engram

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Guided by Hebb’s influential theory on the critical importance of synaptic plasticity (the increase in synaptic strength between neurons) in memory

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Background

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: many researchers showed that enhanced synaptic strength was correlated with memory

What this does not establish

The review calls Hebb’s theory influential; "dominant" is the page’s word for that.

Claim 34 · checked 24 September 2026 · AI-assisted audit

Claim: Engram studies find changes in the intrinsic excitability of cells working alongside it.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: both increased intrinsic excitability and synaptic plasticity work hand in hand to form engrams

What this does not establish

In rodents.

Later work looked for

Europe PMC, 2021 on, "engram": later work (for example on excitability-based allocation, 2024, and on forgetting as engram plasticity, 2022) extends the rodent findings; none reports the manipulations in people.

Corrected

24 September 2026. Previously: “Alternatives point to the intrinsic excitability of cells,” The review presents excitability as working with synaptic change, not as an alternative to it.

Claim 35 · checked 24 September 2026 · AI-assisted audit

Claim: One hypothesis stores very long-term memories in the pattern of holes in the matrix that wraps neurons,

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    Very long-term memories may be stored in the pattern of holes in the perineuronal netabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Theory · Argument

    The source reads: A hypothesis and the experiments to test it propose that very long-term memories, such as fear conditioning, are stored as the pattern of holes in the perineuronal net (PNN), a specialized ECM that envelops mature neurons and restricts synapse formation.

What this does not establish

A proposal with experiments to test it, not a result. Read as an abstract.

Corrected

24 September 2026. Previously: “to the pattern of holes in the matrix around them,” The source is a hypothesis paper and the sentence now says so.

Claim 36 · checked 24 September 2026 · AI-assisted audit

Claim: and work in mice gives astrocytes a part in forming remote memories.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

What this does not establish

In mice. Astrocytes are shown to help form remote memories, not to store them.

Later work looked for

Europe PMC, 2020 on, astrocytes and memory: found by title only; nothing read that changes the mouse result.

Corrected

24 September 2026. Previously: “and to roles for astrocytes.” The cited paper shows astrocytes contributing to how remote memories form in mice, not an alternative place where memory is kept.

Claim 37 · checked 24 September 2026 · AI-assisted audit

Claim: The synaptic account is well supported and probably incomplete.

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

The page’s judgement, following from claims 34 to 37.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: both increased intrinsic excitability and synaptic plasticity work hand in hand to form engrams

Claim 38 · checked 24 September 2026 · AI-assisted audit

What sleep is doing to it

Claim: What sleep is doing to it

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: Sleep benefits memory,

Kind
What the field holds. The settled view of a field, as a review, a consensus statement or a reference work gives it. Not one study.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    About sleep’s role in memoryAbstract

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: Over more than a century of research has established the fact that sleep benefits the retention of memory.

  • Qualifies

    How robust are sleep-mediated memory benefits?abstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: several key findings supporting these theories could not be replicated or occurred only under certain conditions, suggesting that effects of sleep on memory are smaller, more task-dependent, less SWS-related, less robust and less long-lasting than previously assumed

What this does not establish

The benefit is smaller and less robust than the 2013 review assumed (claim 42).

Later work looked for

Europe PMC, 2021 on, sleep and memory meta-analyses: Cordi and Rasch 2021 report replication failures and smaller effects, and Berres and Erdfelder 2021 (Psychological Bulletin, abstract, as recorded in the why-do-we-sleep register) find a moderate benefit reduced when selective reporting is allowed for. Page qualified.

Corrected

24 September 2026. Previously: “Sleep clearly benefits memory consolidation,” "Clearly" and "consolidation" stated the size of the effect and its mechanism as settled; a 2021 review reports failed replications and a smaller effect.

Claim 40 · checked 24 September 2026 · AI-assisted audit

Claim: and in rats hippocampal activity patterns from waking are replayed during sleep.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    About sleep’s role in memorySection III A

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: exhibited correlated activity while the rat was running along a track to obtain a food reward. During subsequent SWS, the correlation pattern of these place cells was strikingly similar to the pattern observed during the awake performance.

What this does not establish

Recorded in rat place cells.

Later work looked for

Europe PMC, 2013 on, hippocampal replay during sleep: replay remains a standard finding in rodents; nothing that changes it.

Corrected

24 September 2026. Previously: “and hippocampal activity patterns from waking are replayed during sleep.” The replay the source describes was recorded in rats.

Claim 41 · checked 24 September 2026 · AI-assisted audit

Claim: How large the benefit is has been revised down: a 2021 review, one of whose authors wrote the 2013 review this passage cites, reports key findings that could not be replicated and an effect smaller and less robust than was assumed.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    How robust are sleep-mediated memory benefits?abstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: several key findings supporting these theories could not be replicated or occurred only under certain conditions, suggesting that effects of sleep on memory are smaller, more task-dependent, less SWS-related, less robust and less long-lasting than previously assumed

  • Supports

    How robust are sleep-mediated memory benefits?Crossref records for this review and for Rasch and Born 2013

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026

    The source reads: authors Maren Jasmin Cordi, Björn Rasch; Current Opinion in Neurobiology. ... authors Björn Rasch, Jan Born.

  • Context

    How robust are sleep-mediated memory benefits?Crossref record, authors

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026

    Björn Rasch is an author of this review and of Rasch and Born 2013.

What this does not establish

Read as an abstract only. The review covers declarative memory, and argues the benefit is smaller, not absent.

Later work looked for

Europe PMC, 2021 on, sleep and memory meta-analyses: Cordi and Rasch 2021 report replication failures and smaller effects, and Berres and Erdfelder 2021 (Psychological Bulletin, abstract, as recorded in the why-do-we-sleep register) find a moderate benefit reduced when selective reporting is allowed for. Page qualified.

Corrected

24 September 2026. Previously: “” Added at the coordinator’s direction and on reading the source: the page stated the benefit as settled.

Claim 42 · checked 24 September 2026 · AI-assisted audit

Claim: Sleep appears to favour some memories over others, such as those that were emotional, rewarded or flagged as needed later,

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

What this does not establish

A review making the case for selection; some of the studies it cites have had failed replications or conflicting results, which it notes for emotional memory.

Later work looked for

Europe PMC, 2013 on, sleep and selective consolidation: nothing found that settles the selection question; Cordi and Rasch 2021 find effects more task-dependent.

Corrected

24 September 2026. Previously: “Exactly which memories are selected, and by what criteria, is unresolved.” The cited review does name criteria (emotional salience, reward, expected future use); what it calls uncharacterised is the mechanism.

Claim 43 · checked 24 September 2026 · AI-assisted audit

Claim: but how the sleeping brain does the choosing remains largely uncharacterised.

Kind
Open question. Something the page says is not known.
Review
Presented as open. The page says this is unresolved, and the review found that it is.

  • Supports

    Sleep-dependent memory triage: evolving generalization through selective processingSleep-dependent consolidation: A process of discriminatory selection

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Review of the field

    The source reads: The precise neural mechanisms that initially create waking instructional tags, as well as the mechanisms controlling selective “gating” of consolidation during sleep, remain largely uncharacterized

Claim 44 · checked 24 September 2026 · AI-assisted audit

Questions the laboratory cannot reach

Claim: Questions the laboratory cannot reach

Kind
Framing. Signposting. It asserts nothing a source could check.

How a lifetime is organised

Claim: How a lifetime is organised

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: A person can retrieve a specific afternoon from decades ago without any obvious search.

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

An everyday observation the page offers to set up the question, not a finding.

Claim 47 · checked 24 September 2026 · AI-assisted audit

Claim: The mechanisms in the sections above are about how a memory is held;

Kind
This page’s reading. A judgement the page makes from the evidence. Others read it differently.
Review
A judgement, not a fact. Reviewed for whether it is fairly put and follows from the checked claims. No source can confirm it.

A description of the page’s own sections.

Claim 48 · checked 24 September 2026 · AI-assisted audit

Claim: how a lifetime of them is indexed so that one comes back rather than another is a different question, and this page has found no account of it to point at.

Kind
Open question. Something the page says is not known.
Review
Presented as open. The page says this is unresolved, and the review found that it is.

The page says what it has not found rather than that nothing exists.

Claim 49 · checked 24 September 2026 · AI-assisted audit

Why forgetting works the way it does

Claim: Why forgetting works the way it does

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: Forgetting is not simply decay.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The biology of forgetting: a perspectiveIntrinsic forgetting

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: the brain also has the inherent biological capacity to erode memory traces using signaling systems like those used for acquisition and consolidation

  • Context

    The biology of forgetting: a perspectiveIntroduction

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Although forgetting can occur due to failed retrieval of an intact engram, we emphasize active forgetting

Later work looked for

Europe PMC, 2017 on, "active forgetting" and "engram": Ryan and Frankland 2022 (by title) extend the argument that forgetting is regulated; nothing that reverses it.

Claim 51 · checked 24 September 2026 · AI-assisted audit

Claim: Work in flies and mice has found mechanisms that actively erase memory traces,

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    The biology of forgetting: a perspectiveSummary

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Pioneering research studies, beginning with those using Drosophila, have identified several molecular and cellular mechanisms for active forgetting.

  • Supports

    The biology of forgetting: a perspectiveNeurogenesis-based forgetting

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Indeed, increasing neurogenesis after memory formation promotes forgetting in adult mice.

What this does not establish

In fruit flies and rodents.

Later work looked for

Europe PMC, 2017 on, "active forgetting" and "engram": Ryan and Frankland 2022 (by title) extend the argument that forgetting is regulated; nothing that reverses it.

Corrected

24 September 2026. Previously: “It appears to be actively regulated,” The cited abstract (Richards and Frankland) does not carry active regulation; Davis and Zhong’s review does, in flies and rodents, and is now cited.

Claim 52 · checked 24 September 2026 · AI-assisted audit

Claim: and one proposal holds that forgetting helps learning, by clearing outdated detail so that what is kept generalises.

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    The persistence and transience of memoryabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Theory · Review of the field

    The source reads: transience (1) enhances flexibility, by reducing the influence of outdated information on memory-guided decision-making, and (2) prevents overfitting to specific past events, thereby promoting generalization

What this does not establish

A proposal drawing on neurobiology and computation. Read as an abstract only.

Corrected

24 September 2026. Previously: “and in some cases is necessary for learning.” Stated as fact what Richards and Frankland propose; "necessary" was stronger than their "promoting generalization".

Claim 53 · checked 24 September 2026 · AI-assisted audit

Claim: Where the line falls between a memory that is lost and one that is merely inaccessible is not known, and may not be a well-formed question.

Kind
Open question. Something the page says is not known.
Review
Presented as open. The page says this is unresolved, and the review found that it is.

Silent engrams in mice can be reactivated artificially when natural cues fail, and forgetting can be failed retrieval of an intact trace, so the line is hard to draw.

  • Context

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: “silent” engrams were discovered in amnesic mice; artificial reactivation of silent engrams induces memory retrieval, whereas natural cues cannot

  • Context

    The biology of forgetting: a perspectiveIntroduction

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Although forgetting can occur due to failed retrieval of an intact engram, we emphasize active forgetting

Claim 54 · checked 24 September 2026 · AI-assisted audit

What the relationship is between remembering and imagining

Claim: What the relationship is between remembering and imagining

Kind
Framing. Signposting. It asserts nothing a source could check.

Claim: Patients with hippocampal damage, asked to imagine a commonplace scene they have never been in, produce fragments with no setting to hold them.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Patients with hippocampal amnesia cannot imagine new experiencesAbstract; Methods

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: short verbal cues that outlined a range of simple commonplace scenarios ... The patients' imagined experiences lacked spatial coherence, consisting instead of fragmented images in the absence of a holistic representation of the environmental setting.

What this does not establish

Five patients against ten controls.

Later work looked for

Europe PMC, 2011 on, hippocampus and imagining the future: Squire and others 2010 found imagining intact in hippocampal patients, and Addis and Schacter 2011 review the disagreement ("where do we stand?"); page now reports it.

Claim 56 · checked 24 September 2026 · AI-assisted audit

Claim: Four of the five tested that way were impaired; the fifth was not.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Source checked. The cited passage was read, and it says this.

Later work looked for

Europe PMC, 2011 on, hippocampus and imagining the future: Squire and others 2010 found imagining intact in hippocampal patients, and Addis and Schacter 2011 review the disagreement ("where do we stand?"); page now reports it.

Claim 57 · checked 24 September 2026 · AI-assisted audit

Claim: Its authors took this to mean that the same structure builds the past and the possible.

Kind
What scholars argue. A report of what specialists argue, or where they disagree.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Patients with hippocampal amnesia cannot imagine new experiencesDiscussion, first paragraph

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in people · Experiment

    The source reads: the role of the hippocampus extends beyond reliving past experiences, encompassing not only imagining plausible self-relevant future events, but also more generally the construction of fictitious experiences

Later work looked for

Europe PMC, 2011 on, hippocampus and imagining the future: Squire and others 2010 found imagining intact in hippocampal patients, and Addis and Schacter 2011 review the disagreement ("where do we stand?"); page now reports it.

Corrected

24 September 2026. Previously: “The same structure appears to build the past and the possible.” A study of five patients was stated as the finding; it is its authors’ conclusion, and another group disputes it (claim 59).

Claim 58 · checked 24 September 2026 · AI-assisted audit

Claim: Not every study agrees: a 2010 study of five patients with hippocampal damage found their ability to imagine the future intact.

Kind
Experimental result. What an experiment or trial found, under its own conditions. A result in animals, cells or a simulation is not a result in people.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    Role of the hippocampus in remembering the past and imagining the futureabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Experiment

    The source reads: Five patients with bilateral hippocampal damage and one patient with large medial temporal lobe lesions were tested ... The patients with hippocampal damage had intact remote autobiographical memory, modestly impaired recent memory, and an intact ability to imagine the future.

What this does not establish

Read as an abstract. The tasks differ: Hassabis and others asked for imagined scenes, the 2010 study for plausible future episodes.

Later work looked for

Europe PMC, 2011 on, hippocampus and imagining the future: Squire and others 2010 found imagining intact in hippocampal patients, and Addis and Schacter 2011 review the disagreement ("where do we stand?"); page now reports it.

Corrected

24 September 2026. Previously: “” Added. A rival study found imagining intact after hippocampal damage, and the page reported only one side.

24 September 2026. Previously: “Not every study agrees: in 2010 Larry Squire’s group tested five patients with hippocampal damage and found their ability to imagine the future intact.” The abstract that was read names no authors, so the attribution to Squire’s group is not carried by the recorded evidence; the sentence now names the study instead.

Claim 59 · checked 24 September 2026 · AI-assisted audit

Claim: Whether memory is a system for recording what happened, or a system for simulating what could happen that uses the past as raw material, is genuinely open.

Kind
Open question. Something the page says is not known.
Review
Presented as open. The page says this is unresolved, and the review found that it is.

The second option is Schacter and Addis’s constructive episodic simulation hypothesis.

Claim 60 · checked 24 September 2026 · AI-assisted audit

What memory might be for

Claim: What memory might be for

Kind
Framing. Signposting. It asserts nothing a source could check.

Memory is prediction

Claim: Memory is prediction

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    The persistence and transience of memoryabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Theory · Review of the field

    The source reads: the goal of memory is not the transmission of information through time, per se. Rather, the goal of memory is to optimize decision-making.

  • Supports

    The cognitive neuroscience of constructive memory: remembering the past and imagining the futureabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: some types of memory distortions reflect the operation of adaptive processes. An important function of a constructive episodic memory is to allow individuals to simulate or imagine future episodes, happenings and scenarios.

What this does not establish

A proposal, filed under what memory might be for. Both sources were read as abstracts.

Other readings

The traditional view treats memory as a record whose errors are failures; see claim 6.

Claim 62 · checked 24 September 2026 · AI-assisted audit

Claim: If the point of storing the past is to anticipate the future, then reconstruction is not a flaw in the system. It is the system working.

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    The cognitive neuroscience of constructive memory: remembering the past and imagining the futureabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: some types of memory distortions reflect the operation of adaptive processes. An important function of a constructive episodic memory is to allow individuals to simulate or imagine future episodes, happenings and scenarios.

  • Supports

    The persistence and transience of memoryabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Theory · Review of the field

    The source reads: the goal of memory is not the transmission of information through time, per se. Rather, the goal of memory is to optimize decision-making.

What this does not establish

Written as a conditional. Schacter and Addis argue some distortions reflect adaptive processes, not all. Both sources were read as abstracts only.

Claim 63 · checked 24 September 2026 · AI-assisted audit

Claim: Distortion, blending and updating would be expected consequences of a mechanism optimised for usefulness rather than fidelity.

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Partly checked. Only part of the source could be read. What was not read is listed.

  • Supports

    The persistence and transience of memoryabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Theory · Review of the field

    The source reads: the goal of memory is not the transmission of information through time, per se. Rather, the goal of memory is to optimize decision-making.

  • Supports

    The cognitive neuroscience of constructive memory: remembering the past and imagining the futureabstract

    Cited · Link answered, 19 October 2026 · Abstract only, 24 September 2026 · Research in people · Review of the field

    The source reads: some types of memory distortions reflect the operation of adaptive processes. An important function of a constructive episodic memory is to allow individuals to simulate or imagine future episodes, happenings and scenarios.

What this does not establish

A consequence the page draws from the hypothesis; neither source tests it directly. Both sources were read as abstracts only.

Claim 64 · checked 24 September 2026 · AI-assisted audit

The trace is distributed and partly redundant

Claim: The trace is distributed and partly redundant

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: an emerging concept is that a given memory is supported by an engram complex, composed of functionally connected engram cell ensembles dispersed across multiple brain regions

What this does not establish

The review calls the engram complex an emerging concept, supported in mice.

Claim 65 · checked 24 September 2026 · AI-assisted audit

Claim: A single memory may exist as overlapping patterns across multiple regions,

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureStructured abstract, Advances

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: an emerging concept is that a given memory is supported by an engram complex, composed of functionally connected engram cell ensembles dispersed across multiple brain regions

What this does not establish

Supported by mapping studies in mice; not shown in people.

Claim 66 · checked 24 September 2026 · AI-assisted audit

Claim: which would explain why memories degrade gracefully rather than disappearing,

Kind
Hypothesis. A proposed explanation, not an established one.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureIntroduction, on Hebb’s cell assembly

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Theory · Review of the field

    The source reads: destruction of a fraction of assembly cells would not necessarily produce catastrophic failure of the entire representation (but rather gracefully degrade the representation)

What this does not establish

A property Hebb hypothesised for a cell assembly; the review reports it as a hypothesis.

Claim 67 · checked 24 September 2026 · AI-assisted audit

Claim: and why decades of lesion experiments in rats never found a place where a specific memory was kept.

Kind
Historical claim. A statement about the past that historical evidence can test.
Review
Source checked. The cited passage was read, and it says this.

  • Supports

    Memory engrams: Recalling the past and imagining the futureIntroduction, on Lashley

    Cited · Link answered, 19 October 2026 · Read in full, 24 September 2026 · Research in animals · Review of the field

    The source reads: Lashley trained rats over many days to solve a maze ... Although the amount of cortical tissue removed correlated with overall memory impairment, the location of the lesion did not. After more than 30 years of searching, Lashley failed to find an engram

Corrected

24 September 2026. Previously: “and why no one has found a place where a specific memory is kept.” The engram work in the page’s own second section locates parts of specific memories in mice; what failed to find a single place was Lashley’s lesion programme, which the review describes.

Claim 68 · checked 24 September 2026 · AI-assisted audit

What was read