scabw Wbacs's List: long-term memory

• Short term memory (STM) and long term memory (LTM) are actually not just different in terms of time, they are different in mechanism, in how they form. LTM relies on actual synaptic changes in the brain over a period of time, meaning that new proteins have to be synthesized, while right now we think that STM relies more on increases or decreases in firing rates of neurons, without permanent changes at the cellular level.
• So if LTM formation means that synapses are changed, it's going to require the synthesis of a lot of new proteins, specifically in the area of the hippocampus, a brain area closely associated with learning and memory.
• Thus, is appears that a novel environment before training is a behavioral "tag" that induces protein synthesis, causing memories formed either immediately after or immediately before to become LTMs. A behavioral "tag" induces physical changes in the brain. And it turns out that this is not just hippocampus-dependant. The authors got similar results when they inactivated the hippocampus during training, meaning that the cortex or other areas may also be involved.
• It means that, if you want to store something in your LTM (anybody got a test coming up?), it might help to associate your learning it with something novel. Of course, you can't go out and ride a roller coaster for each new fact, but sometimes writing a haiku or something silly about what you're learning could be novel enough to help form that memory.

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• The study, published in ‘Neuron’ on 3 August, concludes that introducing completely new facts when learning, significantly improves memory performance.
• Researchers have long suspected that the human brain is particularly attracted to new information and that this might be important for learning.
• Current practice by behavioural psychologists aims to improve memory through repeatedly exposing a person to information – just as we do when we revise for an exam. This study shows that revising is more effective if you mix new facts in with the old. You actually learn better, even though your brain is also tied up with new information.
• We believe that experiencing novelty might, in itself, have an impact on our dopamine levels.
• Even the rare and emotional images did not activate the midbrain. It responded only to new images.
• The second experiment, using fMRI, made some of the images more or less familiar to test how this relativity affected brain activity. It did not – only completely new images produced activity in the midbrain area.
• Only completely new things cause strong activity in the midbrain area.
• Subjects performed best in these tests when new information was combined with familiar information during learning. After a 20 minute delay, subjects’ memory for slightly familiar information was boosted by 19 per cent if it had been mixed with new facts during learning sessions.
• “When we see something new, we see it has a potential for rewarding us in some way. This potential that lies in new things motivates us to explore our environment for rewards. The brain learns that the stimulus, once familiar, has no reward associated with it and so it loses its potential. For this reason, only completely new objects activate the midbrain area and increase our levels of dopamine.”

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• Now, researchers Nico Bunzeck and Emrah Düzel report studies with humans showing that the SN/VTA does respond to novelty as such and this novelty motivates the brain to explore, seeking a reward.
• In this method--as the subject's brains were scanned using functional magnetic resonance imaging--they were shown a series of images of the same face or outdoor scene. However, the researchers randomly intermixed in this series four types of different, or "oddball," faces or scenes. One oddball was simply a different neutral image, one was a different image that required the researchers to press a button, one was an emotional image, and one was a distinctly novel image.
• With this experimental design, the researchers could compare the subjects' response to the different kinds of oddball images to distinguish the brain's reaction to pure novelty itself from the other possible sources of brain activation, such as emotional arousal.
• In a second set of oddball experiments, the researchers sought to determine whether the SN/VTA encodes the magnitude of novelty. In those experiments, the researchers measured activation of the region by images of different levels of familiarity or novelty. In yet other studies, the researchers assessed whether the subjects' memory of familiar images was better when presented along with novel images or very familiar images.
• The researchers found that the SN/VTA does, indeed, respond to novelty, and these response scales according to how novel the image was. They concluded that their data provide evidence for "a functional hippocampal-SN/VTA loop" that is driven by novelty rather than other forms of stimulus salience such as emotional content or the need to respond to an image.
• Also, Bunzeck and Düzel found that novelty enhanced learning in the subjects. "Thus, the human SN/VTA can code absolute stimulus novelty and might contribute to enhanced learning in the context of novelty," they concluded.

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• During acquisition of event-related fMRI, the investigators showed subjects pictures of faces or outdoor scenes embodying different attributes of salience and then measured the SN/VTA response to these different stimuli. A first group of pictures was novel, or never seen before. A second group of pictures was behaviorally relevant, requiring a button press. A third group of pictures was negative and thus presumed to be arousing (i.e., a negative expression in the case of faces, or a car accident in the case of scenes). A fourth group of pictures were distinct but appeared more than once (called “neutral oddballs”). When not viewing one of these pictures, subjects saw a repeated neutral picture for the remaining two-thirds of the trials. Pictures appeared about every 3 s.

  The investigators found that among all pictures, novel pictures most powerfully activated the SN/VTA, as well as parts of the hippocampus and striatum, suggesting that SN/VTA activation responded to novelty rather than other types of salience.
• The investigators also examined whether novelty enhances memory. Hippocampal activation has been associated with encoding memories in fMRI studies (Brewer et al., 1998 and Wagner et al., 1998 A.D. Wagner, D.L. Schacter, M. Rotte, W. Koutstaal, A. Maril, A.M. Dale, B.R. Rosen and R.L. Buckner, Science 281 (1998), pp. 1188–1191. View Record in Scopus | Cited By in Scopus (669)Wagner et al., 1998), and novel pictures activated this region as well as the SN/VTA. This leads to the inference that subjects should show superior memory for novel pictures. In fact, they did not. Instead, as in other research (Ranganath and Rainer, 2003), subjects remembered familiar pictures better than novel pictures. However, in a separate experiment, the investigators found an interesting contextual effect in which familiar pictures interspersed with novel pictures got a transient memory boost, detectable 20 min but not 1 day later. This finding can be contrasted with those of other recent studies which show that reward cues coactivate the SN/VTA and hippocampus, which enhances long-term memory not only for the cues (Wittmann et al., 2005), but also for pictures that follow them (Adcock et al., 2006).
• Together, these findings potentially inform an exciting new body of research that attempts to link motivation and memory. A recent theory postulates that two circuits form a loop, by which novelty can promote memory (Lisman and Grace, 2005). In the first descending circuit, novelty activates the hippocampus, which synapses on the SN/VTA via subcortical pathways that pass through the ventral striatum. A second ascending circuit completes the loop, in which the activated SN/VTA releases dopamine in the hippocampus, promoting memorization of the novel stimulus. The present findings provide partial support for the loop theory. They are consistent with recruitment of the first circuit, in which hippocampus, striatum, and SN/VTA are activated by novelty. However, they are not consistent with recruitment of the second circuit, since novel stimuli were not better remembered. However, there was a transient boost in memory for familiar stimuli in the context of novel stimuli. Since other fMRI studies suggest that reward cues activate this second circuit, which corresponds with enhanced encoding of subsequent stimuli, it may be that novel stimuli themselves are not better remembered but put the brain in a receptive state for remembering what is yet to come (which could be a persisting novel stimulus or something else) (Dayan, 2002 and Knutson and Adcock, 2005 B. Knutson and R.A. Adcock, Neuron 45 (2005), pp. 331–332. Article | PDF (49 K)   | View Record in Scopus | Cited By in Scopus (2)Knutson and Adcock, 2005).

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• When you're trying to learn or memorize something, try tossing some new information into the mix.
• Rehashing the same old information over and over is dullsville for the brain, compared to exploring new information, write Nico Bunzeck, MS, and Emrah Duzel, MD, PhD, in Neuron.

• Behavioral psychology currently aims to boost patients' memory through repetition, as in studying for an exam, Duzel notes in a University College London news release.

   

  But studying appears to be "more effective if you mix new facts in with the old," he says. "You actually learn better, even though your brain is also tied up with new information."

• Participants scored best on those tests when oddball images had been part of the series of pictures.

   

  On the brain scans, the SN/VTA showed more activity when people saw the oddball images, compared to images they'd seen many times or just a few times before.

   

  The SN/VTA makes a chemical called dopamine. Novelty may bring a reward in the form of more dopamine, the researchers suggest.

   

  "We believe that experiencing novelty might, in itself, have an impact on our dopamine levels," Duzel says in the university news release.
• The brain is always looking for a reward, and if it's learned that it won't get rewarded by very familiar information, it takes its chances with novelty, the researchers reason.
• "By beginning to trace links between novelty, reward, and memory, Bunzeck and Duzel have given us a good start toward understanding the motivation that drives explorers and scientists alike," write the editorialists.

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• There are some book publishers and authors who have caught on, though. Novelty learners (probably more boys than girls) tend to like books and subjects pushing limits like Guiness Book of World Records or Believe It or Not, space, black holes, infinity, or science fiction, Amazing Facts / Extreme Facts (for instance, for animals), and funny or a little shocking stuff like you might find in Horrible Histories, Calvin & Hobbes, or Cartoon Guide...

• "These experiments indicate that the hippocampus acts as a sort of comparison device, matching up past and present experience” says Dr Kumaran. "It does not appear to be reacting to novelty as such, but rather to discrepancies between what it expects to see and what it actually sees."
• The results imply that when the hippocampus is prompted by a cue, it recalls a sequence of associated memories, a process that may explain how seeing a particular person's face or listening to a piece of music can trigger the recollection of an entire past experience. Furthermore, the hippocampus would appear to perform a critical comparison between our past and present experiences alerting us to unexpected occurrences in our environment, such as changed layout.

• In this article we develop the concept that the hippocampus and the midbrain dopaminergic neurons of the ventral tegmental area (VTA) form a functional loop. Activation of the loop begins when the hippocampus detects newly arrived information that is not already stored in its long-term memory. The resulting novelty signal is conveyed through the subiculum, accumbens, and ventral pallidum to the VTA where it contributes (along with salience and goal information) to the novelty-dependent firing of these cells. In the upward arm of the loop, dopamine (DA) is released within the hippocampus; this produces an enhancement of LTP and learning. These findings support a model whereby the hippocampal-VTA loop regulates the entry of information into long-term memory.

• the largest effect sizes were obtained by interventions that included systematic drill, repetition, practice, and review.
• the largest effect sizes were obtained by interventions that included systematic drill, repetition, practice, and review.
• the largest effect sizes were obtained by interventions that included systematic drill, repetition, practice, and review.
• Its purpose is to create automaticity, so that the child will know something without having to think about it.

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• Wenn Sie sich etwas merken wollen, dann versuchen die entsprechenden Nervenzellen, sich miteinander zu verbinden. Sie strecken und dehnen sich aus, um gegenseitig in Kontakt zu treten. Dieser Effekt hält aber nur einige Minuten lang an. Danach ziehen sich die Nervenzellen wieder zusammen.
• Egal, ob Sie zehn Minuten oder drei Stunden am Stück lernen, Ihr Gehirn hakt das als einmaliges Lernen ab. Erst wenn Sie wiederholen, wird der Stoff als wichtig erkannt - daher sind zehn Minuten an vier Tagen auch sinnvoller als vierzig Minuten an einem Tag.
• Dennoch ist solch eine auswendige Wiederholung sehr wichtig. Denn wenn Sie etwas auf diese Weise einmal wiederholen, merken Sie es sich genauso gut, als wenn Sie den Text 3- bis 4-mal lesen.
• Setzen Sie die erste Wiederholung genau 8 Stunden nach dem Lernvorgang an. Das bedeutet, am nächsten Morgen, wenn Sie gelernt haben, bevor Sie ins Bett gegangen sind. Oder am Abend, wenn Sie sich gegen Mittag mit Ihrem Text befasst haben.
• Die zweite Wiederholung erfolgt genau nach einem Tag, die dritte genau zwei Tage nach der zweiten Wiederholung.
• Sie werden merken, dass Ihr Text sich nun schon so gut in Ihrem Gehirn verfestigt hat, dass Sie ihm ohne Vorlage wiederholen können.
• "Schuld" daran sind die Lernpausen, die Sie machen. In diesen befasst sich Ihr Unterbewusstsein nämlich weiterhin mit dem Text, es verknüpft neue Informationen mit schon vorhandenen und stellt weitere Nervenverbindungen her. Diese tragen dazu bei, dass sich das Gelernte in Ihrem Gehirn verfestigt.
• Den Zeitabstand für diese Wiederholungen können Sie sich selbst setzten: Sie verdoppeln einfach den vorherigen Abstand der Wiederholung. Die nächste Wiederholung fände dann nach vier Tagen, nach acht, 16, einem Monat, zwei Monaten und so weiter statt.
• Nutzen Sie die Zeit in einer Warteschlange oder beim Sport, und wiederholen Sie Ihren Text im Kopf. Jedes halbe Jahr sollten Sie sich dann eine kurze Wiederholung gönnen

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• Wenn Du Grammatikregeln lernst, ist es sinnlos, sie bloß zu lesen oder wortgetreu auswendig zu können. Eine Regel auswendig können heißt, sie mit eigenen Worten und Beispielen darstellen können.
• einen Überblick verschafft
• Skizze
• Lies die Beispielsätze laut vor, betone dabei das, worauf es ankommt
• eigene Beispielsätze
• schreibe einen Beispielsatz auf ein großes Papier. Hänge das Papier auf und erläutere nun auswendig, sozusagen in einem Vortrag, die Regel
• Damit die Ähnlichkeitshemmung (Interferenz) ausgeschaltet wird, lerne immer nur eine Regel zur Zeit
• Auswendig lernen geht dann am besten, wenn wieder möglichst viele Sinne beteiligt sind

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• It used to be that how well a person learned something was thought to depend upon how long it was kept in short-term memory or the number of times they repeated it to themselves. Research evidence now suggests that neither of these factors plays the critical role. Continuous repetition does not necessarily guarantee that something will be remembered. The key factor in transferring information from short-term to long-term memory is the development of associations between the new information and schemata already available in memory. This, in turn, depends upon two variables: the extent to which the information to be learned relates to an already existing schema, and the level of processing given to the new information.
• Such repetition, or maintenance rehearsal, is effective for maintaining the information in STM, but is an inefficient and often ineffective means of transferring it to LTM.
• If the list were changed to juice, cereal, milk, sugar, bacon, eggs, toast, butter, jelly, and coffee, the task would be much easier because the data would then correspond with an existing schema--items commonly eaten for breakfast. Such a list can be assimilated to your existing store of knowledge with little difficulty, just as the chess master rapidly assimilates the positions of many chessmen.
• Depth of processing is the second important variable in determining how well information is retained. Depth of processing refers to the amount of effort and cognitive capacity employed to process information, and the number and strength of associations that are thereby forged between the data to be learned and knowledge already in memory.
• The following illustrative tasks are listed in order of the depth of mental processing required: say how many letters there are in each word on the list, give a word that rhymes with each word, make a mental image of each word, make up a story that incorporates each word.
• This result holds true regardless of whether the test subjects are informed in advance that the purpose of the experiment is to test them on their memory. Advising test subjects to expect a test makes almost no difference in their performance, presumably because it only leads them to rehearse the information in short-term memory, which is ineffective as compared with other forms of processing.
• By Rote. Material to be learned is repeated verbally with sufficient frequency that it can later be repeated from memory without use of any memory aids. When information is learned by rote, it forms a separate schema not closely interwoven with previously held knowledge. That is, the mental processing adds little by way of elaboration to the new information, and the new information adds little to the elaboration of existing schemata. Learning by rote is a brute force technique. It seems to be the least efficient way of remembering.
• By Assimilation. Information is learned by assimilation when the structure or substance of the information fits into some memory schema already possessed by the learner. The new information is assimilated to or linked to the existing schema and can be retrieved readily by first accessing the existing schema and then reconstructing the new information. Assimilation involves learning by comprehension and is, therefore, a desirable method, but it can only be used to learn information that is somehow related to our previous experience.
• By Using A Mnemonic Device. A mnemonic device is any means of organizing or encoding information for the purpose of making it easier to remember.
• To learn the first grocery list of disconnected words, you would create some structure for linking the words to each other and/or to information already in LTM.
• Any form of processing information in this manner is a more effective aid to retention than rote repetition. Even more effective systems for quickly memorizing lists of names or words have been devised by various memory experts, but these require some study and practice in their use.
• Mnemonic devices are useful for remembering information that does not fit any appropriate conceptual structure or schema already in memory. They work by providing a simple, artificial structure to which the information to be learned is then linked. The mnemonic device supplies the mental "file categories" that ensure retrievability of information. To remember, first recall the mnemonic device, then access the desired information.

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