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[0] Káli S, Dayan P, Off-line replay maintains declarative memories in a model of hippocampal-neocortical interactions.Nat Neurosci 7:3, 286-94 (2004 Mar)

[0] Foster DJ, Wilson MA, Reverse replay of behavioural sequences in hippocampal place cells during the awake state.Nature 440:7084, 680-3 (2006 Mar 30)

[0] Li CS, Padoa-Schioppa C, Bizzi E, Neuronal correlates of motor performance and motor learning in the primary motor cortex of monkeys adapting to an external force field.Neuron 30:2, 593-607 (2001 May)[1] Caminiti R, Johnson PB, Urbano A, Making arm movements within different parts of space: dynamic aspects in the primate motor cortex.J Neurosci 10:7, 2039-58 (1990 Jul)

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ref: -2015 tags: PaRAC1 photoactivatable Rac1 synapse memory optogenetics 2p imaging mouse motor skill learning date: 10-30-2019 20:35 gmt revision:1 [0] [head]

PMID-26352471 Labelling and optical erasure of synaptic memory traces in the motor cortex

  • Idea: use Rac1, which has been shown to induce spine shrinkage, coupled to a light-activated domain to allow for optogenetic manipulation of active synapses.
  • PaRac1 was coupled to a deletion mutant of PSD95, PSD delta 1.2, which concentrates at the postsynaptic site, but cannot bind to postsynaptic proteins, thus minimizing the undesirable effects of PSD-95 overexpression.
    • PSD-95 is rapidly degraded by proteosomes
    • This gives spatial selectivity.
  • They then exploited the dendritic targeting element (DTE) of Arc mRNA which is selectively targeted and translated in activiated dendritic segments in response to synaptic activation in an an NMDA receptor dependent manner.
    • Thereby giving temporal selectivity.
  • Construct is then PSD-PaRac1-DTE; this was tested on hippocampal slice cultures.
  • Improved sparsity and labelling further by driving it with the Arc promoter.
  • Motor learning is impaired in Arc KO mice; hence inferred that the induction of AS-PaRac1 by the Arc promoter would enhance labeling during learning-induced potentiation.
  • Delivered construct via in-utero electroporation.
  • Observed rotarod-induced learning; the PaRac signal decayed after two days, but the spine volume persisted in spines that showed Arc / DTE hence PA labeled activity.
  • Now, since they had a good label, performed rotarod training followed by (at variable delay) light pulses to activate Rac, thereby suppressing recently-active synapses.
    • Observed both a depression of behavioral performance.
    • Controlled with a second task; could selectively impair performance on one of the tasks based on ordering/timing of light activation.
  • The localized probe also allowed them to image the synapse populations active for each task, which were largely non-overlapping.

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ref: -0 tags: shape memory polymers neural interface thiolene date: 12-06-2013 22:55 gmt revision:0 [head]

PMID-23852172 A comparison of polymer substrates for photolithographic processing of flexible bioelectronics

  • Describe the deployment of shape-memory polymers for a neural interface
    • Thiol-ene/acrrylate network (see figures)
    • Noble metals react strongly to the thiols, yielding good adhesion.
  • Cr/Au thin films.
  • Devices change modulus as they absorb water; clever!
  • Transfer by polymerization patterning of electrodes (rather than direct sputtering).
    • This + thiol adhesion still might not be sufficient to prevent micro-cracks.
  • "Neural interfaces fabricated on thiol-ene/acrylate substrates demonstrate long-term fidelity through both in vitro impedance spectroscopy and the recording of driven local field potentials for 8 weeks in the auditory cortex of laboratory rats. "
  • Impedance decreases from 1M @ 1kHz to ~ 100k over the course of 8 weeks. Is this acceptable? Seems like the insulator is degrading (increased capacitance; they do not show phase of impedance)
  • PBS uptake @ 37C:
    • PI seems to have substantial PBS uptake -- 2%
    • PDMS the lowest -- 0.22%
    • PEN (polyethelene napathalate) -- 0.36%
    • Thiol-ene/acrylate 2.19%
  • Big problem is that during photolithographic processing all the shape-memory polymers go through Tg, and become soft/rubbery, making thin metal film adhesion difficult.
    • Wonder if you could pattern more flexible materials, e.g. carbon nanotubes (?)
  • Good paper, many useful references!

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ref: -0 tags: artificial intelligence projection episodic memory reinforcement learning date: 08-15-2012 19:16 gmt revision:0 [head]

Projective simulation for artificial intelligence

  • Agent learns based on memory 'clips' which are combined using some pseudo-bayesian method to trigger actions.
    • These clips are learned from experience / observation.
    • Quote: "..more complex behavior seems to arise when an agent is able to “think for a while” before it “decides what to do next.” This means the agent somehow evaluates a given situation in the light of previous experience, whereby the type of evaluation is different from the execution of a simple reflex circuit"
    • Quote: "Learning is achieved by evaluating past experience, for example by simple reinforcement learning".
  • The forward exploration of learned action-stimulus patterns is seemingly a general problem-solving strategy (my generalization).
  • Pretty simple task:
    • Robot can only move left / right; shows a symbol to indicate which way it (might?) be going.

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ref: -0 tags: hippocampus theta oscillations memory date: 03-18-2012 18:09 gmt revision:0 [head]

PMID-21696996 The hippocampus: hub of brain network communication for memory

  • Their hypothesis: memory encoding is dominated by theta oscillations 6-10 Hz; during inactivity, hippocampal neurons burst synchronously, creating sharp waves, theoretically supporting memory consolidation.
  • (They claim): to date there is no generally accepted theoretical view on memory consolidation.
  • Generally it seems to shift from hippocampus to neocortex, but still, evidence is equivocal. (Other than HM & other human evidence?)
  • Posit a theory based on excitation ramps of reverse-replay, which seems a bit fishy to me (figure 3).
  • Didn't know this: replay in visual and PFC can be so precise that it preserves detailed features of the crosscorrelograms between neurons. [58, 65, 81].

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ref: Deco-2009.05 tags: stochastic dynamics Romo memory computation date: 01-16-2012 18:54 gmt revision:1 [0] [head]

PMID-19428958[0] Stochastic dynamics as a principle of brain function

  • Noise produces a 'probabalistic choice'.
  • Used simulated integrate and fire neurons.
  • justification: "and the taking of probabilistic decisions that on an individual trial may be non-optimal, but that may be adaptive by providing evidence about whether the probability of opportunities is changing in the world". So, a broader optimality in an uncertain world?
  • I'm skimming this, but looks like they largely are focused on frequency discrimination tasks.
  • Lots of text.

____References____

[0] Deco G, Rolls ET, Romo R, Stochastic dynamics as a principle of brain function.Prog Neurobiol 88:1, 1-16 (2009 May)

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ref: PENFIELD-1963.12 tags: Penfield memory stimulation music epilepsy awesome date: 12-29-2011 22:21 gmt revision:4 [3] [2] [1] [0] [head]

PMID-14090522[0] The Brains record of auditory and visual experience -- A final summary and discussion

  • 102 pages. basically, this is a book.
  • Electrical stimulation causes 'hallucinations of things previously seen or heard or experienced.'
    • 'Both the experience and the interpretation are produced by discharge in the temporal cortex and not in other areas'
    • Experiential responses only followed stimulation in the temporal lobe.
  • These tests were done in an effort to locate the source of a seizure.
  • Damn, references the Caliph at Cordova as the first to document epileptic hallucinations (1519!)
    • And Hughlings Jackson (1888)!
  • Extirpation of memories elicited by ustim to an area persist after removal of that area.
  • Performed 1,288 surgeries, 520 of them for seizures in the temporal lobes, 40 of these with experiential responses, and 24 of those with experiential epileptic hallucinations.
    • Many of the patients' epilepsy was caused by ischemia, perhaps developmental; others by glioma..
  • Stimulation of the white matter has never produced an experiential response. Deep stimulation in the amygdala or hippocampus (??) also failed to elicit experiential responses.
  • Talks about 'difficult birth' -- was/is this the cause of some epilepsy? Or has that been discounted?
  • Buncha stuff on human cortical anatomy / topology, which is not so interesting to me.
  • Walker on the chimpanzee (1938) showed that the temporal cortex has no direct connections to the thalamus except posteriorly, where projections are received from nucleus lateralis posterior and pulvinar (visual attention), and within the transverse temporal gyri which receive auditory afferent projections from the medial geniculate body.
    • Also receives large fiber projections from the hippocampus.
  • This is absolutely fascinating. Memories, art, songs (music, so much music -- temporal lobe!), childbirth, counting, childhood molestation, a whole host of experiences were brought forth by electrical stimulation.
    • Case 9. E. Le. This 44-year old woman began to have seizures at age 22 during a pregnancy. The attack pattern was: (1) flushing of face and neck (2) automatism; (3) occasional generalized seizure. During and automatism she was apt to say, "I am alright". Then she would walk about the room and show marked affection toward anyone who happened to be present.
    • Repeated without warning: She said, "Yes, another experience, a different experience." Then she added, "A true experience. This man, Mr. Meerburger, he, oh well, he drinks. Twice his boy has run away. I went to the store once for an ice cream cone and I saw that he was back, and I said 'Hmm, he is back,' and the lady asked me 'What is the matter,' and I didn't know how to explain so I said, 'Well you know Mr. Meerburger drinks.' I thought that was the easiest way but later mother told me, no, and it made it a lot worse."
    • What surprises me is the relative lack of breadth in these --many of the responses to stimulation are quite similar, over a wide range of cortex, many of them very dream-like in features and recall.
      • Their impression: It is often evident that ''each stimulation leaves behind a facilitating influence so that the same response follows each stimulation and this facilitation may cause a given response to follow stimulation at one to three centimeters distance. Illustrated by the case 5, D.F
      • This deserves far more experimentation! E.g. ask the patient to think about something, and see if the same stimulation elicits different memories.
    • Another patient had a series of experiential hallucinations which all involved some aspect of 'grabbing' -- a man grabbing a rifle from a cadet during a parade, a man snatching his hat from the hat-check girl, grabbing a stick from a dog's mouth. In this epileptic, an instance of 'grabbing' was the ictal focus. Amazing.
  • Points out that stimulation must activate a great number of neural circuits, only one specific memory is recalled -- indicating that there is strong inhibition for mutual-exclusion.
  • Non-dominant, non-speech temporal cortex is almost always involved in interpretation: stimulation produces visual experiences, or visual interpretive illusions (change in distance or speed).
    • Stimluation also produces changes in the state-of-mind.
  • Certain sorts of experiences seem absent:
    • The times of making up ones mind
    • Times of carrying out skilled acts, writing messages or adding figures,
    • Eating food
    • Sexual excitement and experience (unless the patients may have self-censored this?)
    • Intense pain or suffering.
    • These things do not involve interpretation, and the focus of attention is not on the way that things are heard or seen.
  • They would remove quite large sections of the temporal lobe!
    • Still, the excision of these areas does not abolish memory: it does not contain a record of the past.
    • Yet stimulation in the temporal lobe recalls memories as nowhere else does.
  • There is a sharp frontier / boundary between auditory and visual temporal cortices and interpretive -- millimeters movement may change phosphenes into recall of a familiar person.
  • Note the comparison between speech cortex (dominant) and interpretive -- stimulation of speech cortex produces no speech, only aphasia, whereas stimulation of non-dominant termporal cortex forces recall.
  • "He who is faithfully analysing many cases of epilepsy is doing far more than studying epilepsy"

____References____

[0] PENFIELD W, PEROT P, THE BRAIN'S RECORD OF AUDITORY AND VISUAL EXPERIENCE. A FINAL SUMMARY AND DISCUSSION.Brain 86no Issue 595-696 (1963 Dec)

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ref: BuzsAki-1996.04 tags: hippocampus neocortex theta gamma consolidation sleep Buzsaki review learning memory date: 12-07-2011 02:31 gmt revision:6 [5] [4] [3] [2] [1] [0] [head]

PMID-8670641[0] The hippocampo-neocortical dialogue.

  • the entorhinal ctx is bidirectionally conneted to nearly all areas of the neocortical mantle.
  • Buzsaki correctly predicts that information gathered during exploration is played back at a faster scale during synchronous population busts during (comnsummatory) behaviors.
  • looks like a good review of the hippocampus, but don't have time to read it now.
  • excellent explanation of the anatomy (with some omissions, click through to read the caption):
  • SPW = sharp waves, 40-120ms in duration. caused by synchronous firing in much of the cortex ; occur 0.02 - 3 times/sec in daily activity & during slow wave sleep.
    • BUzsaki thinks that this may be related to memory consolidation.
  • check the cited-by articles : http://cercor.oxfordjournals.org/cgi/content/abstract/6/2/8
____References____
[0] Buzsaiki G, The hippocampo-neocortical dialogue.Cereb Cortex 6:2, 81-92 (1996 Mar-Apr)

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ref: Shadmehr-1997.01 tags: Shadmehr human long term memory learning motor M1 cortex date: 03-25-2009 15:29 gmt revision:2 [1] [0] [head]

PMID-8987766[0] Functional Stages in the Formation of Human Long-Term Motor Memory

  • We demonstrate that two motor maps may be learned and retained, but only if the training sessions in the tasks are separated by an interval of ~5 hr.
  • Analysis of the after-effects suggests that with a short temporal distance, learning of the second task leads to an unlearning of the internal model for the first.
  • many many citations!

____References____

[0] Shadmehr R, Brashers-Krug T, Functional stages in the formation of human long-term motor memory.J Neurosci 17:1, 409-19 (1997 Jan 1)

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ref: Graves-2001.04 tags: sleep memory REM protein synthesis review date: 03-25-2009 15:23 gmt revision:1 [0] [head]

PMID-11250009[0] Sleep and memory: a molecular perspective.

  • inhibition of protein synthesis is most effective if it occurs at a time post-training when rapid eye movement (REM) sleep is required for memory consolidation
  • The neurochemical changes that occur across sleep/wake states, especially the cholinergic changes that occur in the hippocampus during REM sleep, might provide a mechanism by which sleep modulates specific cellular signaling pathways involved in hippocampus-dependent memory storage.
    • REM sleep could influence the consolidation of hippocampus-dependent long-term memory if it occurs during windows that are sensitive to cholinergic or serotonergic signaling.
    • PKA activation seems important to hippocampal long-term memory
    • NMDA affects PKA through Ca2+ to adenyl cyclase
    • 5-HT_1A receptor negatively coupled to adenyl cyclase (AC)
    • 5-HT concentrations go down in hippocampus during sleep ?

____References____

[0] Graves L, Pack A, Abel T, Sleep and memory: a molecular perspective.Trends Neurosci 24:4, 237-43 (2001 Apr)

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ref: Rasch-2009.04 tags: REM learning procedural memory sleep spindles date: 03-23-2009 18:32 gmt revision:3 [2] [1] [0] [head]

PMID-18836440[0] Pharmacological REM sleep suppression paradoxically improves rather than impairs skill memory

  • surpressed REM sleep with SSRIs or norepinephrine reuptake inhibitor
    • yet tested the subjects after a long wash-out: 32 hours, including 2 nights sleep.
  • did not impair word-pair recognition, and improved finger tapping accuracy.
  • sleep spindles are a feature of non-REM sleep.
  • REM sleep is characterized by an abscence of serotonin and norepinephrine; SSRIs and SNRIs increase the levels of these two neurotransmitters, respectively, at the synaptic cleft.
  • clinical studies of depressed patients show no impairment of skill performance during long-term treatment with these drugs, despite marked REM supression
  • did mirror-tracing and finger-tapping tasks.
  • SSRI supressed REM sleep; SNRI almost completely removed REM.
  • treatment increased accuracy of finger tapping task! esp. for the SNRI.
    • increase in accuracy was positively correlated to the change in spindle density.
  • For the mirror task, there were notable improvements after sleep, but no significant difference between placebo, SSRI, and SNRI groups.
  • paired-word retention task has been shown dependent on SWS; it was not affected by pharmacology.
  • They suggest that perhaps SSRI /SNRI supressed simply the typical measures of REM sleep, and that other factors critical for the associated consolidation were unaffected (e.g. high cholinergic activity).
  • result is consistent with [1]

____References____

[0] Rasch B, Pommer J, Diekelmann S, Born J, Pharmacological REM sleep suppression paradoxically improves rather than impairs skill memory.Nat Neurosci no Volume no Issue no Pages (2008 Oct 5)
[1] Tamaki M, Matsuoka T, Nittono H, Hori T, Fast sleep spindle (13-15 hz) activity correlates with sleep-dependent improvement in visuomotor performance.Sleep 31:2, 204-11 (2008 Feb 1)

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ref: Maquet-2001.11 tags: sleep learning memory Maquet date: 03-20-2009 18:38 gmt revision:1 [0] [head]

PMID-11691982[0] The Role of Sleep in Learning and Memory

  • 8 years ago; presumably much has changed?
  • NREM = SWS; REM = PS (paradoxical sleep)
  • nice table in there! looks as though he was careful in background research on this one; plenty of references.
  • "indeed, stress can also lead to an increase in REM sleep." -- but this may only be related to the presence of new material.
    • however, there is no increase in REM sleep if there is no material to learn.
  • reminder that theta rhythm is seen in the hippocampus in both exploratory activity and in REM sleep.
    • anticipated the presence of replay in the hippocampus
  • spindles allow the entry of Ca+2, which facilitates LTP (?).
  • I should check up on songbird learning (mentioned in the review!).
    • Young zebra finches have to establish the correspondence between vocal production (motor output) and the resulting auditory feedback (sensory).
    • This cannot be done during waking because the bird song arises from tightly time-coded sequence of activity; during sleep, however, motor output can be compared to sensory feedback (so as to capture an inverse model?)
  • PGO (ponto-geniculo-occipital) waves occur immediately before REM sleep. PGO waves are more common in rats after aversive training.
  • ACh increases cortical plasticity in adult mammals; REM sleep is characterized by a high level of ACh and 5-HT (serotonin).
---
  • sleep may not be necessary for recall-based learning, it just may be a goot time for it. Sharp waves and ripples are observed in both quiet waking and SWS.
  • Learning to reach in a force field is consolidated in 5 hours after training. [1]
  • Again mentions the fact that antidipressant drugs, which drastically reduce the amount of REM sleep, do not aversely affect memory.

____References____

[0] Maquet P, The role of sleep in learning and memory.Science 294:5544, 1048-52 (2001 Nov 2)
[1] Shadmehr R, Brashers-Krug T, Functional stages in the formation of human long-term motor memory.J Neurosci 17:1, 409-19 (1997 Jan 1)

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ref: Stickgold-2001.11 tags: review dream sleep REM NREM SWS learning memory replay date: 03-19-2009 17:09 gmt revision:7 [6] [5] [4] [3] [2] [1] [head]

PMID-11691983[0] Sleep, Learning, and Dreams: Off-line Memory Reprocessing

  • sleep can be broadly divided into REM (rapid eye movement) and NREM (no rapid eye movement) sleep, with the REM-NREM cycle lasting 90 minutes in humans.
  • REM seems involved in proper binocular wiring in the visual cortex, development of problem solving skills, and discrimination tasks.
    • REM sleep seems as important as visual experience for wiring binocular vision.
  • REM seems critical for learning procedural memories, but not declarative (by the authors claim that the tasks used in declarative tests are too simple).
    • Depriving rats of REM sleep can impair procedural learning at test points up to a week later.
    • SWS may be better for consolidation of declarative memory.
  • Strongest evidence comes from a visual texture discrimination task, where improvements are only seen after REM sleep.
    • REM has also been shown to have an effect in learning of complex logic games, foreign language acquisition, and after intensive studying.
    • Solving anagrames stronger after being woken up from REM sleep. (!)
  • REM (hypothetically) involves NC -> hippocampus; SWS involves hippocampus -> NC (hence declarative memory). (Buzaki 1996).
    • This may use theta waves, which enhance LTP in the hippocampus; the slow large depolarizations in SWS may facilitate LTP in the cortex.
  • Replay in the rat hippocampus:
    • replay occurs within layer CA1 during SWS for a half hour or so after learning, and in REM after 24 hours.
    • replay shifts from being in-phase with the theta wave activity (e.g. helping LTP) to being out of phase (coinicident with troughs, possibly used to 'erase' memories from the hippocampus?); this is in accord with memories becoming hippocampally independent.
  • ACh levels are at waking levels or higher, and levels of NE (noradrenergic) & 5-HT go near zero.
  • DLPFC (dorsolateral prefrontal cortex) is inhibited during REM sleep - presumably, this results in an inability to allocate attentional resources.
  • ACC (anterior cingulate cortex), MFC (medial frontal cortex), and the amygdala are highly active in REM sleep.
  • if you block correlates of learning - PKA pathwat, zif-268 genes during REM, learning is impaired.
  • In the context of a multilevel system of sleep-dependent memory reprocessing, dreams represent the conscious awareness of complex brain systems involved in the reprocessing of emotions and memories during sleep.
    • the whole section on dreaming is really interesting!

____References____

[0] Stickgold R, Hobson JA, Fosse R, Fosse M, Sleep, learning, and dreams: off-line memory reprocessing.Science 294:5544, 1052-7 (2001 Nov 2)

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ref: KAli-2004.03 tags: hippocampus memory model Dayan replay learning memory date: 03-06-2009 17:53 gmt revision:1 [0] [head]

PMID-14983183[0] Off-line replay maintains declarative memories in a model of hippocampal-neocortical interactions

  • (i'm skimming the article)
  • The neocortex acts as a probabilistic generative model. unsupervised learning extracts categories, tendencies and correlations from the statistics of the inputs into the [synaptic weights].
  • Their hypothesis is that hippocampal replay is required for maintenance of episodic memories; their model and simulations support this.
  • quote: "However, the computational goal of episodic learning is storing individual events rather than discovering statistical structure, seemingly rendering consolidation inappropriate. If initial hippocampal storage of the episode already ensures that it can later be recalled episodically, then, barring practical advantages such as storage capacity (or perhaps efficiency), there seems little point in duplicating this capacity in neocortex." makes sense!

____References____

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ref: Foster-2006.03 tags: hippocampus memory place cells reverse replay Wilson date: 03-06-2009 17:53 gmt revision:1 [0] [head]

PMID-16474382[0] Reverse replay of behavioral sequences in hippocampal place cells during the awake state.

  • wow: they show compressed reverse replay of firing sequences of hippocampal place cells during movement. While the rat is awake, too!
  • recorded up to 128 cells from the rat hippocampus; 4 animals.
  • the replay occurred while the rat was stopped, and lasted a few hundred milliseconds (~300).
  • phenomena appears to be very common, at least for the rats on the novel tracks.
  • replay events were coincident with ripples in the hippocampal EEG, which also occurs during sleep.
    • however, during slow-wave sleep, the replay was forward.
  • they offer a reasonable hypothesis for the reverse replay's function: it is used to propagate value information from the rewarded lcoation backwards along incoming (behavioral) trajectories.
    • quote "awake replay represents efficient use of hard-won experience."

____References____

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ref: Pearlmutter-2009.06 tags: sleep network stability learning memory date: 02-05-2009 19:21 gmt revision:1 [0] [head]

PMID-19191602 A New Hypothesis for Sleep: Tuning for Criticality.

  • Their hypothesis: in the course of learning, the brain's networks move closer to instability, as the process of learning and information storage requires that the network move closer to instability.
    • That is, a perfectly stable network stores no information: output is the same independent of input; a highly unstable network can potentially store a lot of information, or be a very selective or critical system: output is highly sensitive to input.
  • Sleep serves to restore the stability of the network by exposing it to a variety of inputs, checking for runaway activity, and adjusting accordingly. (inhibition / glia? how?)
  • Say that when sleep is not possible, an emergency mechanism must com into play, namely tiredness, to prevent runaway behavior.
  • (From wikipedia:) a potentially serious side-effect of many antipsychotics is that they tend to lower a individual's seizure threshold. Recall that removal of all dopamine can inhibit REM sleep; it's all somehow consistent, but unclear how maintaining network stability and being able to move are related.

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ref: Li-2001.05 tags: Bizzi motor learning force field MIT M1 plasticity memory direction tuning transform date: 09-24-2008 22:49 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-11395017[0] Neuronal correlates of motor performance and motor learning in the primary motor cortex of monkeys adapting to an external force field

  • this is concerned with memory cells, cells that 'remember' or remain permanently changed after learning the force-field.
  • In the above figure, the blue lines (or rather vertices of the blue lines) indicate the firing rate during the movement period (and 200ms before); angular position indicates the target of the movement. The force-field in this case was a curl field where force was proportional to velocity.
  • Preferred direction of the motor cortical units changed when the preferred driection of the EMGs changed
  • evidence of encoding of an internal model in the changes in tuning properties of the cells.
    • this can suppor both online performance and motor learning.
    • but what mechanisms allow the motor cortex to change in this way???
  • also see [1]

____References____

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ref: bookmark-0 tags: memory supermemo leraning psychology Hermann Ebbinghaus date: 05-08-2008 15:25 gmt revision:0 [head]

http://www.wired.com/medtech/health/magazine/16-05/ff_wozniak -- wonderful article, well written. Leaves you with a sense of Piotr Wozniak (SuperMemo's inventor) crazy, slightly surreal, impassioned, purposeful, but self-regressive (and hence fundamentally stationary) life.

  • Quote: SuperMemo was like a genie that granted Wozniak a wish: unprecedented power to remember. But the value of what he remembered depended crucially on what he studied, and what he studied depended on his goals, and the selection of his goals rested upon the efficient acquisition of knowledge, in a regressive function that propelled him relentlessly along the path he had chosen.
  • http://www.wired.com/images/article/magazine/1605/ff_wozniak_graph_f.jpg
  • Quote: This should lead to radically improved intelligence and creativity. The only cost: turning your back on every convention of social life.

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ref: -0 tags: blackfin BF532 memory map date: 11-21-2007 21:18 gmt revision:1 [0] [head]

page 6 on the spec sheet. 55

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ref: notes-0 tags: blackfin BF537 memory map date: 08-01-2007 19:23 gmt revision:0 [head]

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ref: bookmark-0 tags: muscle artifial catalyst nanotubes shape-memory alloy date: 0-0-2006 0:0 revision:0 [head]

http://www.newscientist.com/article/dn8859-methanolpowered-artificial-muscles-start-to-flex.html

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ref: bookmark-0 tags: Linux device_drivers memory virtual_memory PCI address_translation date: 0-0-2006 0:0 revision:0 [head]

http://www.tldp.org/LDP/khg/HyperNews/get/devices/addrxlate.html