encoding

Reading information aloud to yourself improves memory

  • A lab experiment finds we remember written information better when we read it aloud, and that this is more due to the self involvement than to the motor aspect of producing the words.

Confirming what many of us have learned through practical experience, a study comparing different strategies of reading or listening has found that you are more likely to remember something if you read it out loud to yourself.

In the study, 75 undergraduate students first spent around 15 minutes being recorded as they read aloud 160 common words. They were not told any reason for this activity. Two weeks later, they attended another short session, in which they were told that they would be given the same words they had read earlier, and they would then be tested on their memory of them. Half of the 160 words were given to them in four learning conditions (20 words in each):

  • reading silently
  • hearing someone else read
  • listening to a recording of oneself reading (taken from the first session)
  • reading aloud.

They were then given a self-paced recognition test involving all 160 words, and had to classify each one as “studied” or “new”.

The expected pattern of performance was consistent with that hypothesized: reading aloud was best, followed by hearing oneself, then hearing another, and finally reading silently. There was not a lot of difference between saying aloud and hearing oneself, however — words that were said aloud were only marginally better remembered than those in which one heard oneself say the word (hit rate of 77% vs 74%). Hearing someone else speak was significantly better than simply reading silently (69% vs 65%) (I know, it doesn’t seem much more different, but the first comparison didn’t reach statistical significance, and the second did, just). Much clearer was the comparison between those conditions with a self-referential component (reading aloud, hearing yourself) vs conditions with no such component — here the difference was very clearly significant. This was supported by the results of an unplanned comparison between the hear-self and hear-other conditions, which also produced a significant difference.

These results are consistent with previous research, though the differences are smaller than previous. It seems likely that this might be due to the necessity for participants to have previously experienced the words in the earlier session (obviously it would have been much better to have a substantially longer period between the sessions; I assume logistical issues were behind this choice).

In any case, the findings do support the idea that reading aloud helps memory through all three of its ‘extra’ components:

  • the motor aspect in producing the word
  • the auditory aspect in hearing the word
  • the self-referential aspect of being associated with one self.

Notably, this study suggests that it is the third of these (self-referential) that is the most important aspect, with the motor aspect being least important.

https://www.eurekalert.org/pub_releases/2017-12/uow-sfr113017.php

Reference: 

tags memworks: 

Topics: 

tags strategies: 

Gist memory may be why false memories are more common in older adults

  • Gist processing appears to play a strong role in false memories.
  • Older adults rely on gist memory more.
  • Older adults find it harder to recall specific sensory details that would help confirm whether a memory is true.

Do older adults forget as much as they think, or is it rather that they ‘misremember’?

A small study adds to evidence that gist memory plays an important role in false memories at any age, but older adults are more susceptible to misremembering because of their greater use of gist memory.

Gist memory is about remembering the broad story, not the details. We use schemas a lot. Schemas are concepts we build over time for events and experiences, in order to relieve the cognitive load. They allow us to respond and process faster. We build schemas for such things as going to the dentist, going to a restaurant, attending a lecture, and so on. Schemas are very useful, reminding us what to expect and what to do in situations we have experienced before. But they are also responsible for errors of perception and memory — we see and remember what we expect to see.

As we get older, we do of course build up more and firmer schemas, making it harder to really see with fresh eyes. Which means it’s harder for us to notice the details, and easier for us to misremember what we saw.

A small study involving 20 older adults (mean age 75) had participants look at 26 different pictures of common scenes (such as a farmyard, a bathroom) for about 10 seconds, and asked them to remember as much as they could about the scenes. Later, they were shown 300 pictures of objects that were either in the scene, related to the scene (but not actually in the scene), or not commonly associated to the scene, and were required to say whether or not the objects were in the picture. Brain activity was monitored during these tests. Performance was also compared with that produced in a previous identical study, involving 22 young adults (mean age 23).

As expected and as is typical, there was a higher hit rate for schematic items and a higher rate of false memories for schematically related lures (items that belong to the schema but didn’t appear in the picture). True memories activated the typical retrieval network (medial prefrontal cortex, hippocampus/parahippocampal gyrus, inferior parietal lobe, right middle temporal gyrus, and left fusiform gyrus).

Activity in some of these regions (frontal-parietal regions, left hippocampus, right MTG, and left fusiform) distinguished hits from false alarms, supporting the idea that it’s more demanding to retrieve true memories than illusory ones. This contrasts with younger adults who in this and previous research have displayed the opposite pattern. The finding is consistent, however, with the theory that older adults tend to engage frontal resources at an earlier level of difficulty.

Older adults also displayed greater activation in the medial prefrontal cortex for both schematic and non-schematic hits than young adults did.

While true memories activated the typical retrieval network, and there were different patterns of activity for schematic vs non-schematic hits, there was no distinctive pattern of activity for retrieving false memories. However, there was increased activity in the middle frontal gyrus, middle temporal gyrus, and hippocampus/parahippocampal gyrus as a function of the rate of false memories.

Imaging also revealed that, like younger adults, older adults also engage the ventromedial prefrontal cortex when retrieving schematic information, and that they do so to a greater extent. Activation patterns also support the role of the mediotemporal lobe (MTL), and the posterior hippocampus/parahippocampal gyrus in particular, in determining true memories from false. Note that schematic information is not part of this region’s concern, and there was no consistent difference in activation in this region for schematic vs non-schematic hits. But older adults showed this shift within the hippocampus, with much of the activity moving to a more posterior region.

Sensory details are also important for distinguishing between true and false memories, but, apart from activity in the left fusiform gyrus, older adults — unlike younger adults — did not show any differential activation in the occipital cortex. This finding is consistent with previous research, and supports the conclusion that older adults don’t experience the recapitulation of sensory details in the same way that younger adults do. This, of course, adds to the difficulty they have in distinguishing true and false memories.

Older adults also showed differential activation of the right MTG, involved in gist processing, for true memories. Again, this is not found in younger adults, and supports the idea that older adults depend more on schematic gist information to assess whether a memory is true.

However, in older adults, increased activation of both the MTL and the MTG is seen as rates of false alarms increase, indicating that both gist and episodic memory contribute to their false memories. This is also in line with previous research, suggesting that memories of specific events and details can (incorrectly) provide support for false memories that are consistent with such events.

Older adults, unlike young adults, failed to show differential activity in the retrieval network for targets and lures (items that fit in with the schema, but were not in fact present in the image).

What does all this mean? Here’s what’s important:

  • older adults tend to use schema information more when trying to remember
  • older adults find it harder to recall specific sensory details that would help confirm a memory’s veracity
  • at all ages, gist processing appears to play a strong role in false memories
  • memory of specific (true) details can be used to endorse related (but false) details.

What can you do about any of this? One approach would be to make an effort to recall specific sensory details of an event rather than relying on the easier generic event that comes to mind first. So, for example, if you’re asked to go to the store to pick up orange juice, tomatoes and muesli, you might end up with more familiar items — a sort of default position, as it were, because you can’t quite remember what you were asked. If you make an effort to remember the occasion of being told — where you were, how the other person looked, what time of day it was, other things you talked about, etc — you might be able to bring the actual items to mind. A lot of the time, we simply don’t make the effort, because we don’t think we can remember.

https://www.eurekalert.org/pub_releases/2018-03/ps-fdg032118.php

Reference: 

Topics: 

tags problems: 

tags development: 

tags memworks: 

Eye movements get re-enacted when we remember

  • An imaging and eye-tracking study has shown that the brain uses eye movements to help us recall remembered images.

A small study has tested the eminent Donald Hebb’s hypothesis that visual imagery results from the reactivation of neural activity associated with viewing images, and that the re-enactment of eye-movement patterns helps both imagery and neural reactivation.

In the study, 16 young adults (aged 20-28) were shown a set of 14 distinct images for a few seconds each. They were asked to remember as many details of the picture as possible so they could visualize it later on. They were then cued to mentally visualize the images within an empty rectangular box shown on the screen.

Brain imaging and eye-tracking technology revealed that the same pattern of eye movements and brain activation occurred when the image was learned and when it was recalled. During recall, however, the patterns were compressed (which is consistent with our experience of remembering, where memories take a much shorter time than the original experiences).

Our understanding of memory is that it’s constructive — when we remember, we reconstruct the memory from separate bits of information in our database. This finding suggests that eye movements might be like a blueprint to help the brain piece together the bits in the right way.

https://www.eurekalert.org/pub_releases/2018-02/bcfg-cga021318.php

Reference: 

tags memworks: 

Topics: 

Drawing best encoding strategy

  • Even quick and not particularly skilled sketches make simple information significantly more likely to be remembered, probably because drawing incorporates several factors that are known to improve memorability.

In a series of experiments involving college students, drawing pictures was found to be the best strategy for remembering lists of words.

The basic experiment involved students being given a list of simple, easily drawn words, for each of which they had 40 seconds to either draw the word, or write it out repeatedly. Following a filler task (classifying musical tones), they were given 60 seconds to then recall as many words as possible. Variations of the experiment had students draw the words repeatedly, list physical characteristics, create mental images, view pictures of the objects, or add visual details to the written letters (such as shading or other doodles).

In all variations, there was a positive drawing effect, with participants often recalling more than twice as many drawn than written words.

Importantly, the quality of the drawings didn’t seem to matter, nor did the time given, with even a very brief 4 seconds being enough. This challenges the usual explanation for drawing benefits: that it simply reflects the greater time spent with the material.

Participants were rated on their ability to form vivid mental images (measured using the VVIQ), and questioned about their drawing history. Neither of these factors had any reliable effect.

The experimental comparisons challenge various theories about why drawing is beneficial:

  • that it processes the information more deeply (when participants in the written word condition listed semantic characteristics of the word, thus processing it more deeply, the results were no better than simply writing out the word repeatedly, and drawing was still significantly better)
  • that it evokes mental imagery (when some students were told to mentally visualize the object, their recall was intermediate between the write and draw conditions)
  • that it simply reflects the fact that pictures are remembered better (when some students were shown a picture of the target word during the encoding time, their recall performance was not significantly better than that of the students writing the words)

The researchers suggest that it is a combination of factors that work together to produce a greater effect than the sum of each. These factors include mental imagery, elaboration, the motor action, and the creation of a picture. Drawing brings all these factors together to create a stronger and more integrated memory code.

http://www.eurekalert.org/pub_releases/2016-04/uow-ntr042116.php

Reference: 

[4245] Wammes JD, Meade ME, Fernandes MA. The drawing effect: Evidence for reliable and robust memory benefits in free recall. The Quarterly Journal of Experimental Psychology [Internet]. 2016 ;69(9):1752 - 1776. Available from: http://dx.doi.org/10.1080/17470218.2015.1094494

Source: 

tags memworks: 

tags study: 

Topics: 

tags strategies: 

Improve learning with co-occurring novelty

  • An animal study shows that following learning with a novel experience makes the learning stronger.
  • A human study shows that giving information positive associations improves your memory for future experiences with similar information.

We know that the neurotransmitter dopamine is involved in making strong memories. Now a mouse study helps us get more specific — and suggests how we can help ourselves learn.

The study, involving 120 mice, found that mice tasked with remembering where food had been hidden did better if they had been given a novel experience (exploring an unfamiliar floor surface) 30 minutes after being trained to remember the food location.

This memory improvement also occurred when the novel experience was replaced by the selective activation of dopamine-carrying neurons in the locus coeruleus that go to the hippocampus. The locus coeruleus is located in the brain stem and involved in several functions that affect emotion, anxiety levels, sleep patterns, and memory. The dopamine-carrying neurons in the locus coeruleus appear to be especially sensitive to environmental novelty.

In other words, if we’re given attention-grabbing experiences that trigger these LC neurons carrying dopamine to the hippocampus at around the time of learning, our memories will be stronger.

Now we already know that emotion helps memory, but what this new study tells us is that, as witness to the mice simply being given a new environment to explore, these dopamine-triggering experiences don’t have to be dramatic. It’s suggested that it could be as simple as playing a new video game during a quick break while studying for an exam, or playing tennis right after trying to memorize a big speech.

Remember that we’re designed to respond to novelty, to pay it more attention — and, it seems, that attention is extended to more mundane events that occur closely in time.

Emotionally positive situations boost memory for similar future events

In a similar vein, a human study has found that the benefits of reward extend forward in time.

In the study, volunteers were shown images from two categories (objects and animals), and were financially rewarded for one of these categories. As expected, they remembered images associated with a reward better. In a second session, however, they were shown new images of animals and objects without any reward. Participants still remembered the previously positively-associated category better.

Now, this doesn’t seem in any way surprising, but the interesting thing is that this benefit wasn’t seen immediately, but only after 24 hours — that is, after participants had slept and consolidated the learning.

Previous research has shown similar results when semantically related information has been paired with negative, that is, aversive stimuli.

https://www.eurekalert.org/pub_releases/2016-09/usmc-rim090716.php

http://www.eurekalert.org/pub_releases/2016-06/ibri-eps061516.php

Reference: 

Source: 

tags memworks: 

Topics: 

tags strategies: 

Digital media may be changing how you think

  • Reading from a screen may encourage users to focus on concrete details rather than more abstract thinking.

Four studies involving a total of more than 300 younger adults (20-24) have looked at information processing on different forms of media. They found that digital platforms such as tablets and laptops for reading may make you more inclined to focus on concrete details rather than interpreting information more abstractly.

As much as possible, the material was presented on the different media in identical format.

In the first study, 76 students were randomly assigned to complete the Behavior Identification Form on either an iPad or a print-out. The Form assesses an individual's current preference for concrete or abstract thinking. Respondents have to choose one of two descriptions for a particular behavior — e.g., for “making a list”, the choice of description is between “getting organized” or “writing things down”. The form presents 25 items.

There was a marked difference between those filling out the form on the iPad vs on a physical print-out, with non-digital users showing a significantly higher preference for abstract descriptions than digital users (mean of 18.56 vs 13.75).

In the other three studies, the digital format was always a PDF on a laptop. In the first of these, 81 students read a short story by David Sedaris, then answered 24 multichoice questions on it, of which half were abstract and half concrete. Digital readers scored significantly lower on abstract questions (48% vs 66%), and higher on concrete questions (73% vs 58%).

In the next study, 60 students studied a table of information about four, fictitious Japanese car models for two minutes, before being required to select the superior model. While one model was objectively superior in regard to the attributes and attribute rating, the amount of detail means (as previous research has shown) that those employing a top-down “gist” processing do better than those using a bottom-up, detail-oriented approach. On this problem, 66% of the non-digital readers correctly chose the superior model, compared to 43% of the digital readers.

In the final study, 119 students performed the same task as in the preceding study, but all viewed the table on a laptop. Before viewing the table, however, some were assigned to one of two priming activities: a high-level task aimed at activating more abstract thinking (thinking about why they might pursue a health goal), or a low-level task aimed at activating more concrete thinking (thinking about how to pursue the same goal).

Being primed to think more abstractly did seem to help these digital users, with 48% of this group correctly answering the car judgment problem, compared to only 25% of those given the concrete priming activity, and 30% of the control group.

I note that the performance of the control group is substantially below the performance of the digital users in the previous study, although there was no apparent change in the methodology. However, this was not noted or explained in the paper, so I don't know why this was. It does lead me not to put too much weight on this idea that priming can help.

However, the findings do support the view that reading on digital devices does encourage a more concrete style of thinking, reinforcing the idea that we are inclined to process information more shallowly when we read it from a screen.

Of course, this is, as the researchers point out, not an indictment. Sometimes, this is the best way to approach certain tasks. But what it does suggest is that we need to consider what sort of processing is desirable, and modify our strategy accordingly. For example, you may find it helpful to print out material that requires a high level of abstract thinking, particularly if your degree of expertise in the subject means that it carries a high cognitive load.

http://www.eurekalert.org/pub_releases/2016-05/dc-dmm050516.php

Reference: 

Kaufman, G., & Flanagan, M. (2016). High-Low Split : Divergent Cognitive Construal Levels Triggered by Digital and Non-digital Platforms. Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 1–5. doi:10.1145/2858036.2858550 http://dl.acm.org/citation.cfm?doid=2858036.2858550

Topics: 

tags study: 

tags memworks: 

tags strategies: 

Being overweight linked to poorer memory

  • A study of younger adults adds to evidence that higher BMI is associated with poorer cognition, and points to a specific impairment in memory integration.

A small study involving 50 younger adults (18-35; average age 24) has found that those with a higher BMI performed significantly worse on a computerised memory test called the “Treasure Hunt Task”.

The task involved moving food items around complex scenes (e.g., a desert with palm trees), hiding them in various locations, and indicating afterward where and when they had hidden them. The test was designed to disentangle object, location, and temporal order memory, and the ability to integrate those separate bits of information.

Those with higher BMI were poorer at all aspects of this task. There was no difference, however, in reaction times, or time taken at encoding. In other words, they weren't slower, or less careful when they were learning. Analysis of the errors made indicated that the problem was not with spatial memory, but rather with the binding of the various elements into one coherent memory.

The results could suggest that overweight people are less able to vividly relive details of past events. This in turn might make it harder for them to keep track of what they'd eaten, perhaps making overeating more likely.

The 50 participants included 27 with BMI below 25, 24 with BMI 25-30 (overweight), and 8 with BMI over 30 (obese). 72% were female. None were diagnosed diabetics. However, the researchers didn't take other health conditions which often co-occur with obesity, such as hypertension and sleep apnea, into account.

This is a preliminary study only, and further research is needed to validate its findings. However, it's significant in that it adds to growing evidence that the cognitive impairments that accompany obesity are present early in adult life and are not driven by diabetes.

The finding is also consistent with previous research linking obesity with dysfunction of the hippocampus and the frontal lobe.

http://www.eurekalert.org/pub_releases/2016-02/uoc-bol022616.php

https://www.theguardian.com/science/neurophilosophy/2016/mar/03/obesity-linked-to-memory-deficits

Reference: 

[4183] Cheke LG, Simons JS, Clayton NS. Higher body mass index is associated with episodic memory deficits in young adults. The Quarterly Journal of Experimental Psychology [Internet]. 2015 :1 - 12. Available from: http://dx.doi.org/10.1080/17470218.2015.1099163

Source: 

tags lifestyle: 

tags problems: 

Topics: 

tags memworks: 

Concrete thinking may reduce the power of traumatic memories

  • Focusing on concrete details when experiencing a traumatic event may, oddly enough, protect you more from the power of those memories, than if you tried to distance yourself from what you are experiencing.

Can you help protect yourself from the memory of traumatic events? A new study suggests that, by concentrating on concrete details as you live through the event, you can reduce the number of intrusive memories later experienced.

The study, aimed particularly at those who deliberately expose themselves to the risk of PTSD (e.g., emergency workers, military personnel, journalists in conflict zones), involved 50 volunteers who rated their mood before watching several films with traumatic scenes. After the first film, they rated their feelings. For the next four films, half the participants were asked to consider abstract questions, such as why such situations happened. The other half were asked to consider concrete questions, such as what they could see and hear and what needed to be done from that point. Afterward, they gave another rating on their mood. Finally, they were asked to watch a final film in the same way as they had practiced, rating feelings of distress and horror as they had for the first film.

The volunteers were then given a diary to record intrusive memories of anything they had seen in the films for the next week.

Both groups, unsurprisingly, saw their mood decline after the films, but those who had been practicing concrete thinking were less affected, and also experienced less intense feelings of distress and horror when watching the final film. Abstract thinkers experienced nearly twice as many intrusive memories in the following week.

The study follows previous findings that emergency workers who adopted an abstract processing approach showed poorer coping, and that those who processed negative events using abstract thinking experienced a longer period of low mood, compared to those using concrete thinking.

Further study to confirm this finding is of course needed in real-life situations, but this does suggest a strategy that people who regularly experience trauma could try. It is particularly intriguing because, on the face of it, it would seem like quite the wrong strategy. Distancing yourself from the trauma you're experiencing, trying to see it as something less real, seems a more obvious coping strategy. This study suggests it is exactly the wrong thing to do.

It also seems likely that this tendency to use concrete or abstract processing may reflect a more general trait. Self-reported proneness to intrusive memories in everyday life was significantly correlated with intrusive memories of the films. Perhaps we should all think about the way we view the world, and those of us who tend to take a more abstract approach should try paying more attention to concrete details. This is, after all, something I've been recommending in the context of fighting sensory impairment and age-related cognitive decline!

Abstract thinking certainly has its place, but as I've said before, we need flexibility. Effective cognitive management is about tailoring your style of thinking to the task's demands.

http://www.eurekalert.org/pub_releases/2016-05/uoo-tdc050516.php

Reference: 

tags memworks: 

Topics: 

tags problems: 

Individuals vary in how they remember events

  • Individuals vary in how vividly they remember the past. A new study links this to differences in brain activity which may reflect a stable trait.
  • The finding also has implications for assessments of age-related cognitive decline.

A study involving 66 healthy young adults (average age 24) has revealed that different individuals have distinct brain connectivity patterns that are associated with different ways of experiencing and remembering the past.

The participants completed an online questionnaire on how well they remember autobiographical events and facts, then had their brains scanned. Brain scans found that those with richly-detailed autobiographical memories had higher mediotemporal lobe connectivity to regions at the back of the brain involved in visual perception, whereas those tending to recall the past in a factual manner showed higher mediotemporal lobe connectivity to prefrontal regions involved in organization and reasoning.

The finding supports the idea that those with superior autobiographical memory have a greater ability or tendency to reinstate rich images and perceptual details, and that this appears to be a stable personality trait.

The finding also raises interesting questions about age-related cognitive decline. Many people first recognize cognitive decline in their increasing difficulty retrieving the details of events. But this may be something that is far more obvious and significant to people who are used to retrieving richly-detailed memories. Those who rely on a factual approach may be less susceptible.

http://www.eurekalert.org/pub_releases/2015-12/bcfg-wiy121015.php

Full text available at http://www.sciencedirect.com/science/article/pii/S0010945215003834

Reference: 

Source: 

tags memworks: 

Topics: 

tags problems: 

Memory capacity of brain 10 times more than thought

  • New measurements have exploded the previous estimates of the human brain's memory capacity, and also help explain how neurons have such computational power when their energy use is so low.

The question of the brain's capacity usually brings up remarks that the human brain contains about 100 billion neurons. If each one has, say, 1,000 or more connections to other neurons, this produces some 100 trillion connections in which our memory can be held. These connections are between synapses, which change in strength and size when activated. These changes are a critical part of the memory code. In fact, synaptic strength is analogous to the 1s and 0s that computers use to encode information.

But, here's the thing: unlike the binary code of computers, there are more than two sizes available to synapses. On the basis of the not-very-precise tools researchers had available, they had come up with three sizes: small, medium and large. They also had calculated that the difference between the smallest and largest was a factor of 60.

Here is where the new work comes in, because new techniques have enabled researchers to now see that synapses have far more options open to them. Synapses can, it seems, vary by as little as 8%, creating a possible 26 different sizes available, which corresponds to storing 4.7 bits of information at each synapse, as opposed to one or two.

Despite the precision that this 8% speaks to, hippocampal synapses are notoriously unreliable, with signals typically activating the next neuron only 10-20% of the time. But this seeming unreliability is a feature not a bug. It means a single spike isn't going to do the job; what's needed is a stable change in synaptic strength, which comes from repeated and averaged inputs. Synapses are constantly adjusting, averaging out their success and failure rates over time.

The researchers calculate that, for the smallest synapses, about 1,500 events cause a change in their size/ability (20 minutes), while for the largest synapses, only a couple hundred signaling events (1 to 2 minutes) cause a change. In other words, every 2 to 20 minutes, your synapses are going up or down to the next size, in response to the signals they're receiving.

Based on this new information, the new estimate is that the brain can hold at least a petabyte of information, about as much as the World Wide Web currently holds. This is ten times more than previously estimated.

At the moment, only hippocampal neurons have been investigated. More work is needed to determine whether the same is true across the brain.

In the meantime, the work has given us a better notion of how memories are encoded in the brain, increased the potential capacity of the human brain, and offers a new way of thinking about information networks that may enable engineers to build better, more energy-efficient, computers.

http://www.eurekalert.org/pub_releases/2016-01/si-mco012016.php

http://www.scientificamerican.com/article/new-estimate-boosts-the-human-brain-s-memory-capacity-10-fold/

Full text at http://elifesciences.org/content/4/e10778v2

Reference: 

tags memworks: 

Topics: 

Pages

Subscribe to RSS - encoding