Strategies

Frequent multitaskers are the worst at it

March, 2013

A survey of college students found that those who scored highest in multitasking ability were also least likely to multitask, while those who scored lowest were most likely to engage in it.

I’ve reported often on the perils of multitasking. Here is yet another one, with an intriguing new finding: it seems that the people who multitask the most are those least capable of doing so!

The study surveyed 310 undergraduate psychology students to find their actual multitasking ability, perceived multitasking ability, cell phone use while driving, use of a wide array of electronic media, and personality traits such as impulsivity and sensation-seeking.

Those who scored in the top quarter on a test of multitasking ability tended not to multitask. Some 70% of participants thought they were above average at multitasking, and perceived multitasking ability (rather than actual) was associated with multitasking. Those with high levels of impulsivity and sensation-seeking were also more likely to multitask (with the exception of using a cellphone while driving, which wasn’t related to impulsivity, though it was related to sensation seeking).

The findings suggest that those who multitask don’t do so because they are good at multitasking, but because they are poor at focusing on one task.

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Memory for Facebook posts better than that of faces and books

February, 2013

Gossipy content and informal language may lie behind people's better recall of Facebook posts compared to memory for human faces or sentences from books.

Online social networking, such as Facebook, is hugely popular. A series of experiments has explored the intriguing question of whether our memories are particularly ‘tuned’ to remember the sort of information shared on such sites.

The first experiment involved 32 college students (27 female), who were asked to study either 100 randomly chosen Facebook posts, or 100 sentences randomly chosen from books on Amazon. After the study period (which involved each sentence being presented for 3 seconds), the students were given a self-paced recognition test, in which the 100 study sentences were mixed with another 100 sentences from the same source, with participants responding with a number expressing their confidence that they had (or had not) seen the sentence before (e.g., ‘1’ would indicate they were completely confident that they hadn’t seen it before, ‘20’ that they were totally confident that they had).

Recognition of Facebook posts was significantly better than recognition of sentences from books (an average of 85% correct vs 76%). The ‘Facebook advantage’ remained even when only posts with more normal surface-level characteristics were analyzed (i.e., all posts containing irregularities of spelling and typography were removed).

In the next experiment, involving 16 students (11 female), Facebook posts (a new set) were compared with neutral faces. Again, memory for Facebook posts was substantially better than that for faces. This is quite remarkable, since humans have a particular expertise for faces and tend to score highly on recognition tests for them.

One advantage the Facebook posts might have is in eliciting social thinking. The researchers attempted to test this by comparing the learning achieved when people were asked to count the words of each sentence or post, against the learning achieved when they were asked to think of someone they knew (real or fictional) who could have composed such a sentence / post. This experiment involved 64 students (41 female).

The deeper encoding encouraged by the latter strategy did improve memory for the texts, but it did so equally. The fact that it helped Facebook posts as much as it did book sentences argues against the idea that the Facebook advantage rests on social elaboration (because if so, encouraging them to be socially elaborated would have little extra effect).

Another advantage the Facebook posts might have over book sentences is that they were generally complete in themselves, making sense in a way that randomly chosen sentences from books would not. Other possibilities have to do with the gossipy nature of Facebook posts, and the informal language used. To test these theories, 180 students (138 female) were shown text from two CNN twitter feeds: Breaking News and Entertainment News. Texts included headlines, sentences, and comments.

Texts from Entertainment News were remembered significantly better than those from Breaking News (supporting the gossip advantage). Headlines were remembered significantly better than random sentences (supporting the completeness argument), but comments were remembered best of all (supporting the informality theory) — although the benefit of comments over headlines was much greater for Breaking News than Entertainment News (perhaps reflecting the effort the Entertainment News people put into making catchy headlines?).

It seems then, that three factors contribute to the greater memorability of Facebook posts: the completeness of ideas; the gossipy content; the casually generated language.

You’ll have noticed I made a special point of noting the gender imbalance in the participant pools. Given gender differences in language and social interaction, it’s a shame that the participants were so heavily skewed, and I would like this replicated with males before generalizing. However, the evidence for the advantage of more informal language is, at least, less likely to be skewed by gender.

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Correcting misinformation isn’t just a matter of providing the correct information

February, 2013

A study emphasizes the importance of establishing source credibility when trying to correct false information.

I’ve discussed before how hard it is to correct false knowledge. This is not only a problem for the classroom — the preconceptions students bring to a topic, and the difficulty of replacing them with the correct information — but, in these days of so much misinformation in the media and on the web, an everyday problem.

An internet study involving 574 adults presented them with an article discussing the issue of electronic health records (EHRs). They were then shown another article on the subject, supposedly from a "political blog". This text included several false statements about who was allowed access to these records (for example, that hospital administrators, health insurance companies, employers, and government officials had unrestricted access).

For some participants, this article was annotated so that the false statements were clearly marked, and directions explained that an independent fact-checking organization had found these factual errors. Other participants completed an unrelated three-minute task at the end of reading the text before being presented with the same corrections, while a third group was not advised of the inaccuracies at all (until being debriefed).

After reading the text, participants were given a questionnaire, where they listed everything they had learned about EHRs from the text, rated their feelings about each item, and marked on a 7-point scale how easy it would be for specific groups to access the records. They were also asked to judge the credibility of the fact-checking message.

Those who received the immediate corrections were significantly more accurate than those who received the delayed corrections, and both were significantly more accurate than those receiving no corrections — so at least we know that correcting false information does make a difference! More depressingly, however, the difference between any of the groups, although significant, was small — i.e., correcting false statements makes a difference, but not much of one.

Part of the problem lies, it appears, in people’s preconceptions. A breakdown by participant’s feelings on the issue revealed that the immediate correction was significantly more effective for those who were ‘for’ EHRs (note that the corrections agreed with their beliefs). Indeed, for those unfavorably disposed, the immediate corrections may as well have been no corrections at all.

But, intriguingly, predisposition only made a difference when the correction was immediate, not when it was delayed.

Mapping these results against participants’ responses to the question of credibility revealed that those unfavorably disposed (and therefore prone to believing the false claims in the text) assigned little credibility to the corrections.

Why should this, perfectly understandable, difference apply only when corrections were immediate? The researchers suggest that, by putting the corrections in direct competition with the false statements, more emphasis is put on their relative credibility — assessments of which tend to be biased by existing attitudes.

The findings suggest it is naïve to expect that it is enough to simply tell people something is false, if they have a will to believe it. It also suggests the best approach to correcting false knowledge is to emphasize the credibility of the corrector.

Of course, this study used politically charged information, about which people are likely to have decided opinions. But the results are a reminder that, as the researcher says: "Humans aren't vessels into which you can just pour accurate information. Correcting misperceptions is really a persuasion task.”

This is true even when the information is something as ‘factual’ as the cause of the seasons! Even teachers should take on board this idea that, when new information doesn’t fit in with a student’s world-view, then credibility of the source/authority (the teacher!) is paramount.

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Garrett, R., & Weeks, B. (2013). The Promise and Peril of Real-Time Corrections to Political Misperceptions. Proceedings of the Computer Supported Cooperative Work and Social Computing conference. Retrieved from http://wp.comm.ohio-state.edu/misperceptions/wp-content/uploads/2012/07/...

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Intensive training helps seniors with long-term aphasia

February, 2013

A six-week specific language therapy program not only improved chronic aphasic’s ability to name objects, but produced durable changes in brain activity that continued to bring benefits post-training.

Here’s an encouraging study for all those who think that, because of age or physical damage, they must resign themselves to whatever cognitive impairment or decline they have suffered. In this study, older adults who had suffered from aphasia for a long time nevertheless improved their language function after six weeks of intensive training.

The study involved nine seniors with chronic aphasia and 10 age-matched controls. Those with aphasia were given six weeks of intensive and specific language therapy, after which they showed significantly better performance at naming objects. Brain scans revealed that the training had not only stimulated language circuits, but also integrated the default mode network (the circuits used when our brain is in its ‘resting state’ — i.e., not thinking about anything in particular), producing brain activity that was similar to that of the healthy controls.

Moreover, these new circuits continued to be active after training, with participants continuing to improve.

Previous research has implicated abnormal functioning of the default mode network in other cognitive disorders.

Although it didn’t reach significance, there was a trend suggesting that the level of integration of the default mode network prior to therapy predicted the outcome of the training.

The findings are especially relevant to the many seniors who no longer receive treatment for stroke damage they may have had for many years. They also add to the growing evidence for the importance of the default mode network. Changes in the integration of the default mode network with other circuits have also been implicated in age-related cognitive decline and Alzheimer’s.

Interestingly, some research suggests that meditation may help improve the coherence of brainwaves that overlap the default mode network. Meditation, already shown to be helpful for improving concentration and focus, may be of greater benefit for fighting age-related cognitive decline than we realize!

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Checklists dramatically reduce errors in operating room crises

February, 2013

A simulated study of life-threatening surgical crises has found that using a checklist reduced the omission of critical steps from 23% to 6%.

I reported recently on how easily and quickly we can get derailed from a chain of thought (or action). In similar vein, here’s another study that shows how easy it is to omit important steps in an emergency, even when you’re an expert — which is why I’m a great fan of checklists.

Checklists have been shown to dramatically decrease the chances of an error, in areas such as flying and medicine. However, while surgeons may use checklists as a matter of routine (a study a few years ago found that the use of routine checklists before surgery substantially reduced the chances of a serious complication — we can hope that everyone’s now on board with that!), there’s a widespread belief in medicine that operating room crises are too complex for a checklist to be useful. A new study contradicts that belief.

The study involved 17 operating room teams (anesthesia staff, operating room nurses, surgical technologists, a surgeon), who participated in 106 simulated surgical crisis scenarios in a simulated operating room. Each team was randomized to manage half of the scenarios with a set of crisis checklists and the remaining scenarios from memory alone.

When checklists were used, the teams were 74% less likely to miss critical steps. That is, without a checklist, nearly a quarter (23%) of the steps were omitted (an alarming figure!), while with a checklist, only 6% of the steps were omitted on average. Every team performed better when the checklists were available.

After experiencing these situations, almost all (97%) participants said they would want these checklists used if they experienced such a crisis if they were a patient.

It’s comforting to know that airline pilots do have checklists to use in emergency situations. Now we must hope that hospitals come on board with this as well (up-to-date checklists and implementation materials can be found at www.projectcheck.org/crisis).

For the rest of us, the study serves as a reminder that, however practiced we may think we are, forgetting steps in an action plan is only too common, and checklists are an excellent means of dealing with this — in emergency and out.

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Self-imagination helps memory in both healthy and memory-impaired

December, 2012

A small study involving patients with TBI has found that the best learning strategies are ones that call on the self-schema rather than episodic memory, and the best involves self-imagination.

Sometime ago, I reported on a study showing that older adults could improve their memory for a future task (remembering to regularly test their blood sugar) by picturing themselves going through the process. Imagination has been shown to be a useful strategy in improving memory (and also motor skills). A new study extends and confirms previous findings, by testing free recall and comparing self-imagination to more traditional strategies.

The study involved 15 patients with acquired brain injury who had impaired memory and 15 healthy controls. Participants memorized five lists of 24 adjectives that described personality traits, using a different strategy for each list. The five strategies were:

  • think of a word that rhymes with the trait (baseline),
  • think of a definition for the trait (semantic elaboration),
  • think about how the trait describes you (semantic self-referential processing),
  • think of a time when you acted out the trait (episodic self-referential processing), or
  • imagine acting out the trait (self-imagining).

For both groups, self-imagination produced the highest rates of free recall of the list (an average of 9.3 for the memory-impaired, compared to 3.2 using the baseline strategy; 8.1 vs 3.2 for the controls — note that the controls were given all 24 items in one list, while the memory-impaired were given 4 lists of 6 items).

Additionally, those with impaired memory did better using semantic self-referential processing than episodic self-referential processing (7.3 vs 5.7). In contrast, the controls did much the same in both conditions. This adds to the evidence that patients with brain injury often have a particular problem with episodic memory (knowledge about specific events). Episodic memory is also particularly affected in Alzheimer’s, as well as in normal aging and depression.

It’s also worth noting that all the strategies that involved the self were more effective than the two strategies that didn’t, for both groups (also, semantic elaboration was better than the baseline strategy).

The researchers suggest self-imagination (and semantic self-referential processing) might be of particular benefit for memory-impaired patients, by encouraging them to use information they can more easily access (information about their own personality traits, identity roles, and lifetime periods — what is termed the self-schema), and that future research should explore ways in which self-imagination could be used to support everyday memory tasks, such as learning new skills and remembering recent events.

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Meditation can produce enduring changes in emotional processing

December, 2012

A new study provides more evidence that meditation changes the brain, and different types of meditation produce different effects.

More evidence that even an 8-week meditation training program can have measurable effects on the brain comes from an imaging study. Moreover, the type of meditation makes a difference to how the brain changes.

The study involved 36 participants from three different 8-week courses: mindful meditation, compassion meditation, and health education (control group). The courses involved only two hours class time each week, with meditation students encouraged to meditate for an average 20 minutes a day outside class. There was a great deal of individual variability in the total amount of meditation done by the end of the course (210-1491 minutes for the mindful attention training course; 190-905 minutes for the compassion training course).

Participants’ brains were scanned three weeks before the courses began, and three weeks after the end. During each brain scan, the volunteers viewed 108 images of people in situations that were either emotionally positive, negative or neutral.

In the mindful attention group, the second brain scan showed a decrease in activation in the right amygdala in response to all images, supporting the idea that meditation can improve emotional stability and response to stress. In the compassion meditation group, right amygdala activity also decreased in response to positive or neutral images, but, among those who reported practicing compassion meditation most frequently, right amygdala activity tended to increase in response to negative images. No significant changes were seen in the control group or in the left amygdala of any participant.

The findings support the idea that meditation can be effective in improving emotional control, and that compassion meditation can indeed increase compassionate feelings. Increased amygdala activation was also correlated with decreased depression scores in the compassion meditation group, which suggests that having more compassion towards others may also be beneficial for oneself.

The findings also support the idea that the changes brought about by meditation endure beyond the meditative state, and that the changes can start to occur quite quickly.

These findings are all consistent with other recent research.

One point is worth emphasizing, in the light of the difficulty in developing a training program that improves working memory rather than simply improving the task being practiced. These findings suggest that, unlike most cognitive training programs, meditation training might produce learning that is process-specific rather than stimulus- or task-specific, giving it perhaps a wider generality than most cognitive training.

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Learning another language boosts white matter

November, 2012

Foreign language learning increases the white matter in the language network and the bridge joining the hemispheres, perhaps helping explain why bilinguals have better executive control.

In my last report, I discussed a finding that intensive foreign language learning ‘grew’ the size of certain brain regions. This growth reflects gray matter increase. Another recent study looks at a different aspect: white matter.

In the study, monthly brain scans were taken of 27 college students, of whom 11 were taking an intensive nine-month Chinese language course. These brain scans were specifically aimed at tracking white matter changes in the students’ brains.

Significant changes were indeed observed in the brains of the language learners. To the researchers’ surprise, however, the biggest changes were observed in an area not previously considered part of the language network: the white matter tracts that cross the corpus callosum, the main bridge between the hemispheres. (I’m not quite sure why they were surprised, since a previous study had found that bilinguals showed higher white matter integrity in the corpus callosum.)

Significant changes were also observed within the left-hemisphere language network and in the right temporal lobe. The rate of increase in white matter was linear, showing a steady progression with each passing month.

The researchers suggest that plasticity in the adult brain may differ from that seen in children’s brains. While children’s brains change mainly through the pruning of unwanted connections and the death of unwanted cells, adult brains may rely mainly on neurogenesis and myelinogenesis.

The growth of new myelin is a process that is still largely mysterious, but it’s suggested that activity at the axons (the extensions of neurons that carry the electrical signals) might trigger increases in the size, density, or number of oligodendrocytes (the cells responsible for the myelin sheaths). This process is thought to be mediated by astrocytes, and in recent years we have begun to realize that astrocytes, long regarded as mere ‘support cells’, are in fact quite important for learning and memory. Just how important is something researchers are still working on.

The finding of changes between the frontal hemispheres and caudate nuclei is consistent with a previously-expressed idea that language learning requires the development of a network to control switching between languages.

Does the development of such a network enhance the task-switching facility in working memory? Previous research has found that bilinguals tend to have better executive control than monolinguals, and it has been suggested that the experience of managing two (or more) languages reorganizes certain brain networks, creating a more effective basis for executive control.

As in the previous study, the language studied was very different from the students’ native language, and they had no previous experience of it. The level of intensity was of course much less.

I do wonder if the fact that the language being studied was Mandarin Chinese limits the generality of these findings. Because of the pictorial nature of the written language, Chinese has been shown to involve a wider network of regions than European languages.

Nevertheless, the findings add to the evidence that adult brains retain the capacity to reorganize themselves, and add to growing evidence that we should be paying more attention to white matter changes.

Reference: 

[3143] Schlegel AA, Rudelson JJ, Tse PU. White Matter Structure Changes as Adults Learn a Second Language. Journal of Cognitive Neuroscience [Internet]. 2012 ;24(8):1664 - 1670. Available from: http://dx.doi.org/10.1162/jocn_a_00240

Bialystok, E., Craik, F. I. M., & Luk, G. (2012). Bilingualism: consequences for mind and brain. Trends in Cognitive Sciences, 16(4), 240–250. doi:10.1016/j.tics.2012.03.001

Luk, G. et al. (2011) Lifelong bilingualism maintains white matter integrity in older adults. J. Neurosci. 31, 16808–16813

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Growing the brain with a new language

November, 2012

A new study adds to the growing evidence for the cognitive benefits of learning a new language, and hints at why some people might be better at this than others.

A small Swedish brain imaging study adds to the evidence for the cognitive benefits of learning a new language by investigating the brain changes in students undergoing a highly intensive language course.

The study involved an unusual group: conscripts in the Swedish Armed Forces Interpreter Academy. These young people, selected for their talent for languages, undergo an intensive course to allow them to learn a completely novel language (Egyptian Arabic, Russian or Dari) fluently within ten months. This requires them to acquire new vocabulary at a rate of 300-500 words every week.

Brain scans were taken of 14 right-handed volunteers from this group (6 women; 8 men), and 17 controls that were matched for age, years of education, intelligence, and emotional stability. The controls were medical and cognitive science students. The scans were taken before the start of the course/semester, and three months later.

The brain scans revealed that the language students showed significantly greater changes in several specific regions. These regions included three areas in the left hemisphere: the dorsal middle frontal gyrus, the inferior frontal gyrus, and the superior temporal gyrus. These regions all grew significantly. There was also some, more selective and smaller, growth in the middle frontal gyrus and inferior frontal gyrus in the right hemisphere. The hippocampus also grew significantly more for the interpreters compared to the controls, and this effect was greater in the right hippocampus.

Among the interpreters, language proficiency was related to increases in the right hippocampus and left superior temporal gyrus. Increases in the left middle frontal gyrus were related to teacher ratings of effort — those who put in the greatest effort (regardless of result) showed the greatest increase in this area.

In other words, both learning, and the effort put into learning, had different effects on brain development.

The main point, however, is that language learning in particular is having this effect. Bear in mind that the medical and cognitive science students are also presumably putting in similar levels of effort into their studies, and yet no such significant brain growth was observed.

Of course, there is no denying that the level of intensity with which the interpreters are acquiring a new language is extremely unusual, and it cannot be ruled out that it is this intensity, rather than the particular subject matter, that is crucial for this brain growth.

Neither can it be ruled out that the differences between the groups are rooted in the individuals selected for the interpreter group. The young people chosen for the intensive training at the interpreter academy were chosen on the basis of their talent for languages. Although brain scans showed no differences between the groups at baseline, we cannot rule out the possibility that such intensive training only benefited them because they possessed this potential for growth.

A final caveat is that the soldiers all underwent basic military training before beginning the course — three months of intense physical exercise. Physical exercise is, of course, usually very beneficial for the brain.

Nevertheless, we must give due weight to the fact that the brain scans of the two groups were comparable at baseline, and the changes discussed occurred specifically during this three-month learning period. Moreover, there is growing evidence that learning a new language is indeed ‘special’, if only because it involves such a complex network of processes and brain regions.

Given that people vary in their ‘talent’ for foreign language learning, and that learning a new language does tend to become harder as we get older, it is worth noting the link between growth of the hippocampus and superior temporal gyrus and language proficiency. The STG is involved in acoustic-phonetic processes, while the hippocampus is presumably vital for the encoding of new words into long-term memory.

Interestingly, previous research with children has suggested that the ability to learn new words is greatly affected by working memory span — specifically, by how much information they can hold in that part of working memory called phonological short-term memory. While this is less important for adults learning another language, it remains important for one particular category of new words: words that have no ready association to known words. Given the languages being studied by these Swedish interpreters, it seems likely that much if not all of their new vocabulary would fall into this category.

I wonder if the link with STG is more significant in this study, because the languages are so different from the students’ native language? I also wonder if, and to what extent, you might be able to improve your phonological short-term memory with this sort of intensive practice.

In this regard, it’s worth noting that a previous study found that language proficiency correlated with growth in the left inferior frontal gyrus in a group of English-speaking exchange students learning German in Switzerland. Is this difference because the training was less intensive? because the students had prior knowledge of German? because German and English are closely related in vocabulary? (I’m picking the last.)

The researchers point out that hippocampal plasticity might also be a critical factor in determining an individual’s facility for learning a new language. Such plasticity does, of course, tend to erode with age — but this can be largely counteracted if you keep your hippocampus limber (as it were).

All these are interesting speculations, but the main point is clear: the findings add to the growing evidence that bilingualism and foreign language learning have particular benefits for the brain, and for protecting against cognitive decline.

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Rest briefly after learning

October, 2012

A small study with older adults provides support for the idea that learning is helped if you follow it with a few minutes ‘wakeful rest’.

Back in 2010, I briefly reported on a study suggesting that a few minutes of ‘quiet time’ could help you consolidate new information. A new study provides more support for this idea.

In the first experiment, 14 older adults (aged 61-81) were told a short story, with instructions to remember as many details as possible. Immediately afterward, they were asked to describe what happened in the story. Ten minutes then elapsed, during which they either rested quietly (with eyes closed in a darkened room), or played a spot-the-difference game on the computer (comparing pairs of pictures). This task was chosen because it was non-verbal and sufficiently different from the story task to not directly compete for cognitive resources.

This first learning phase was followed by five minutes of playing the spot-the-difference game (for all participants) and then a second learning phase, in which the process was repeated with a second story, and participants experienced the other activity during the delay period (e.g., rest if they had previously played the game).

Some 30 minutes after the first story presentation (15 minutes after the second), participants were unexpectedly asked to once again recall as many details as they could from the stories. A further recall test was also given one week later.

Recall on the first delayed test (at the end of both learning phases) was significantly better for stories that had been followed by wakeful resting rather than a game. While recall declined at the same rate for both story conditions, the benefits of wakeful resting were maintained at the test one week later.

In a second experiment, the researchers looked at whether these benefits would still occur if there was no repetition (i.e., no delayed recall test at the time, only at a week). Nineteen older adults (61-87) participated.

As expected, in the absence of the short-delay retrieval test, recall at a week was slightly diminished. Nevertheless, recall for stories that had been followed by rest was still significantly better than recall for stories followed by the game.

It’s worth noting that, in a post-session interview, only 3 participants (of the 33 total) reported thinking about the story during the period of wakeful rest. One participant fell asleep. Twelve participants reported thinking about the stories at least once during the week, but there was no difference between these participants’ scores and those who didn’t think about them.

These findings support the idea that a quiet period of reflection after new learning helps the memories be consolidated. While the absence of interfering information may underlie this, the researchers did select the game specifically to interfere as little as possible with the story task. Moreover, the use of the same task as a ‘filler’ between the two learning phases was also designed to equalize any interference it might engender.

The weight of the evidence, therefore, is that ten minutes of wakeful resting aided memory by providing the mental space in which to consolidate the memory. Moreover, the fact that so few participants actively thought about the stories during that rest indicates that such consolidation is automatic and doesn’t require deliberate rehearsal.

The study did, of course, only involve older adults. I hope we will see a larger study with a wider participant pool.

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