Time scales of memory, learning, and plasticity

Time scales of memory, learning, and plasticity Tetzlaff Kolodziejski Markelic Wörgötter

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Time scales of memory, learning, and plasticity 2012 Biological Cybernetics 10.1007/s00422-012-0529-z Tetzlaff2012-time-scales-of-memory-learning-and-plasticit Tetzlaff2012-time-scales-of-memory-learning-and-plasticit.txt, the project's staged copy e5f2a8b86d75e02785bfceaed386176754d22671 not-redistributable neuroscience

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0 spans located by searching the stored text for the quote's exact words, allowing any whitespace between them mechanism Quotation withheld because this record is not cleared for redistribution. time scales of memory, learning, and synaptic plasticity Quotation withheld because this record is not cleared for redistribution. review review Quotation withheld because this record is not cleared for redistribution. mechanisms Forgetting on finite, graded storage times acts as an implicit compression algorithm, holding down both the capacity needed and the time to retrieve an item Quotation withheld because this record is not cleared for redistribution. mechanisms New memories overwrite and interfere with old ones, which lowers the network's capacity demand but destroys important items - the cost that multiple time scales exist to avoid Quotation withheld because this record is not cleared for redistribution. mechanisms Hebbian potentiation feeds back on itself - a strengthened synapse drives the postsynaptic neuron harder, which strengthens it further - producing runaway weight growth unless a counteracting mechanism is present Quotation withheld because this record is not cleared for redistribution. mechanisms An organism evolves a given memory time scale only if its lifespan and environment exert evolutionary pressure for correlations at that scale Quotation withheld because this record is not cleared for redistribution. mechanisms Spike-triggered calcium influx into the presynaptic terminal raises release probability (facilitation) while use depletes the vesicle pool (depression), giving synapses a seconds-long memory Quotation withheld because this record is not cleared for redistribution. The review is selective rather than exhaustive; only key findings are discussed for each link. what this limits: the review's coverage: TO AVOID THIS, ONLY KEY FINDINGS ARE DISCUSSED Quotation withheld because this record is not cleared for redistribution. The mapping from physiological mechanism to behaviour is not established, so the links presented are possibilities rather than established correspondences. what this limits: every mechanism-to-behaviour link the review draws: BECAUSE IT IS NOT CLEAR WHICH MECHANISM IS RESPONSIBLE FOR WHICH BEHAVIOR, WE DISCUSSED POSSIBLE LINKS Quotation withheld because this record is not cleared for redistribution. Only links with existing experimental or modelling support are treated; missing links are flagged as open questions rather than covered. what this limits: the set of links the review treats at all: UP TO THIS POINT WE HAVE ONLY DISCUSSED LINKS FOR WHICH THERE IS ALREADY EXPERIMENTAL SUPPORT OR THEORETICAL MODELING Quotation withheld because this record is not cleared for redistribution. The review's two neighbouring memory categories are given non-overlapping time ranges. what this limits: any use of 'time scale' across these memory terms: working memory is given a range of milliseconds to minutes and short-term memory one of minutes to days, so the expression names different spans for adjacent categories Quotation withheld because this record is not cleared for redistribution. The ordering between the two categories is stated to be unresolved and posed as a question. what this limits: any account of memory transfer drawn from this review: the interaction between short- and long-term memory is said to remain unclear, and whether an item must pass through short-term memory first is asked rather than answered Quotation withheld because this record is not cleared for redistribution. A construct used throughout the learning-algorithm literature has no established physiology for its longer form. what this limits: any physiological reading of eligibility traces: they are used in many learning-algorithm approaches to bridge time gaps, and the authors state the physiological basis of longer traces is unclear Quotation withheld because this record is not cleared for redistribution. working memory working memory Quotation withheld because this record is not cleared for redistribution. short-term memory short-term memory Quotation withheld because this record is not cleared for redistribution. long-term memory long-term memory Quotation withheld because this record is not cleared for redistribution. eligibility traces eligibility traces Quotation withheld because this record is not cleared for redistribution. time scale time scale Quotation withheld because this record is not cleared for redistribution. consolidation → retrieval THE TWO CANNOT BE SEPARATED IN THIS STUDY - the DESIGN form of the negative relation / No edge type can express it: all eight assert that a relation HOLDS. Recorded here because a confounding statement BOUNDS WHAT THE PAPER'S OWN RESULTS CAN MEAN, and it lives in a methods paragraph where nothing downstream will find it. A memory deficit cannot be attributed to either of the two processes the field distinguishes - so the distinction survives in the vocabulary while being unusable on the data. Quotation withheld because this record is not cleared for redistribution. a time scale - THREE DIFFERENT SPANS UNDER ONE EXPRESSION: working memory milliseconds to minutes, short-term memory minutes to days, long-term memory up to what the authors put in scare quotes as 'infinity'; the phrase that organises the whole review denotes a different quantity in each of its three sections Quotation withheld because this record is not cleared for redistribution. long-term memory's upper bound - IN THE AUTHORS' OWN SCARE QUOTES: given as up to 'infinity', with the immediate qualification that it is still under debate how items can be stored for such a long time, so the widest value in the review is the one marked as least settled Quotation withheld because this record is not cleared for redistribution. an eligibility trace - A MODELLING DEVICE WITHOUT ITS PHYSIOLOGY: named in 1943 and used in many learning-algorithm approaches to bridge time gaps, while the physiological basis of the longer traces is stated to be unclear, so the algorithms assume a mechanism the review declines to underwrite Quotation withheld because this record is not cleared for redistribution. builds-on → Martin et al. (2000) four criteria for relating plasticity to learning and memory Quotation withheld because this record is not cleared for redistribution. contradicts → Hebb (1949) proposed link between long-term memory and long-term plasticity Quotation withheld because this record is not cleared for redistribution. working memory —contrasted-with→ short-term memory working memory short-term memory differs in: the span each covers: milliseconds to minutes, versus minutes to days · strength of the relation: 1 Quotation withheld because this record is not cleared for redistribution. Working memory spans milliseconds to minutes, while short-term memory stores items over minutes to days. Quotation withheld because this record is not cleared for redistribution. Having different storage time scales could avoid the deletion of important information. Quotation withheld because this record is not cleared for redistribution. Robot experiments show that when different time scales interact, more complex behaviour can be obtained. Quotation withheld because this record is not cleared for redistribution. Caenorhabditis elegans shows synaptic plasticity but no experience-based structural plasticity. WHOSE RESULT THIS IS: Varshney et al. 2011), long time scale] was found - THE EVIDENCE FOR THIS ROW ATTRIBUTES THE WORK TO SOMEBODY ELSE. The cited name is the subject of a result verb and the sentence carries no first-person marker, so the finding, quantity or definition is the CITED author's rather than this record's. The claim is true and the quote is verbatim - what is wrong is whose result the corpus says it is. Nothing edited, nothing withdrawn: the row is marked so a page can name the source. Where the record is a commentary or review, its claim relations layer usually already names the paper being discussed - the record knows at one layer and forgets at another. Quotation withheld because this record is not cleared for redistribution. Of the proposed memory-physiology links, working memory-to-activity and long-term-memory-to-structural-plasticity have experimental support, whereas the classic long-term-memory-to-long-term-plasticity link is still disputed. Quotation withheld because this record is not cleared for redistribution. So far, mimicry cannot be experimentally induced. Quotation withheld because this record is not cleared for redistribution. Rats in enriched environments build significantly more dendritic spines than controls. Quotation withheld because this record is not cleared for redistribution. Adding synaptic scaling with a quadratic weight dependence to a generic plasticity rule can be shown mathematically to stabilise weight development. Quotation withheld because this record is not cleared for redistribution. Structural plasticity is modelled only computationally because no analytical models of network topology change exist yet. Quotation withheld because this record is not cleared for redistribution. Whether the exact human forgetting curve is exponential or a power law remains unsettled. Quotation withheld because this record is not cleared for redistribution. working memory working memory Quotation withheld because this record is not cleared for redistribution. long-term memory long-term memory Quotation withheld because this record is not cleared for redistribution. chunking chunking Quotation withheld because this record is not cleared for redistribution. detectability detectability Quotation withheld because this record is not cleared for redistribution. retrograde alteration retrograde alteration Quotation withheld because this record is not cleared for redistribution. structural plasticity structural plasticity Quotation withheld because this record is not cleared for redistribution. eligibility traces eligibility traces Quotation withheld because this record is not cleared for redistribution. intrinsic plasticity intrinsic plasticity Quotation withheld because this record is not cleared for redistribution. synaptic tagging synaptic tagging Quotation withheld because this record is not cleared for redistribution. reservoir computing reservoir computing Quotation withheld because this record is not cleared for redistribution. synaptic scaling synaptic scaling Quotation withheld because this record is not cleared for redistribution. about 10 days — how quickly the nervous system's storage capacity would be exhausted if every bit of input were stored Quotation withheld because this record is not cleared for redistribution. four and seven — the number of items working memory can hold Quotation withheld because this record is not cleared for redistribution. tens of milliseconds — the time scale of the postsynaptic potential, the shortest memory-like physiological trace Quotation withheld because this record is not cleared for redistribution. μ = 0.01 corresponds to 100 ms — how the alpha-function time-scale parameter maps onto the filter's temporal duration Quotation withheld because this record is not cleared for redistribution. four — the number of criteria Martin et al. proposed for establishing that plasticity underlies learning and memory (detectability, mimicry, anterograde and retrograde alteration) Quotation withheld because this record is not cleared for redistribution. milliseconds to seconds — the time scale of short-term plasticity Quotation withheld because this record is not cleared for redistribution. hours to several days — the time scale on which structural plasticity rewires the network Quotation withheld because this record is not cleared for redistribution.

The full text of this article is not redistributable, so it is not included here. The evidence sentences are withheld with it; the tag layer and its grounding status remain. The article itself is at https://doi.org/10.1007/s00422-012-0529-z.