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multitasking

Interruptions impact the quality of creative work

Submitted by Fiona McPherson on

In 2013 I reported how a 3-second interruption while doing a task doubled the rate of sequence errors, while a 4s one tripled it. A new study has attempted to measure just how much ongoing interruptions can negatively affect the quality of a complex creative task.

Media multitasking and academic achievement

Submitted by Fiona McPherson on

Three recent studies point to the impact of social media and multiple device use on learning and cognitive control.

College students take years to learn to manage their social media so it doesn't impact their grades

A survey of 1,649 college students has found that freshmen average a total of two hours a day on Facebook, of which over an hour is spent also doing schoolwork, and that time spent on Facebook had a negative impact on their grade point average. For sophomores and juniors, only time spent using Facebook while doing schoolwork affected their GPA.

Frequent multitaskers are the worst at 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.

When multitasking is more of a problem

I’ve reported, often, on the evidence that multitasking is a problem, something we’re not really designed to do well (with the exception of a few fortunate individuals), and that the problem is rooted in our extremely limited working memory capacity. I’ve also talked about how ‘working memory’ is a bit of a misnomer, given that we probably have several ‘working memories’, for different modalities.

How meditation may improve multitasking and attention

Meditation may improve multitasking

I recently reported that developing skill at video action games doesn’t seem to improve general multitasking ability, but perhaps another approach might be more successful. Meditation has, of course, been garnering growing evidence that it can help improve attentional control. A new study extends that research to multitasking in a realistic work setting.

Multitasking

Older news items (pre-2010) brought over from the old website

Improving your multitasking skills

Teaching older brains to regain youthful skills

Researchers have succeeded in training seniors to multitask at the same level as younger adults. Over the course of two weeks, both younger and older subjects learned to identify a letter flashed quickly in the middle of a computer screen and simultaneously localize the position of a spot flashed quickly in the periphery as well as they could perform either task on its own. The older adults did take longer than the younger adults to reach the same level of performance, but they did reach it.

Richards, E., Bennett, P. J., & Sekuler, A. B. (2006). Age related differences in learning with the useful field of view. Vision Research, 46(25), 4217-4231. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/17027061

http://www.eurekalert.org/pub_releases/2006-10/mu-yct100206.php

Age and individual differences

Teen's ability to multi-task develops late in adolescence

A study involving adolescents between 9 and 20 years old has found that the ability to multi-task continues to develop through adolescence. The ability to use recall-guided action to remember single pieces of spatial information (such as looking at the location of a dot on a computer screen, then, after a delay, indicating where the dot had been) developed until ages 11 to 12, while the ability to remember multiple units of information in the correct sequence developed until ages 13 to 15. Tasks in which participants had to search for hidden items in a manner requiring a high level of multi-tasking and strategic thinking continued to develop until ages 16 to 17. "These findings have important implications for parents and teachers who might expect too much in the way of strategic or self-organized thinking, especially from older teenagers."

Luciana, M., Conklin, H. M., Hooper, C. J., & Yarger, R. S. (2005). The Development of Nonverbal Working Memory and Executive Control Processes in Adolescents. Child Development, 76(3), 697-712.

http://www.eurekalert.org/pub_releases/2005-05/sfri-tat051205.php

About multitasking

Stress disrupts task-switching, but the brain can bounce back

A new neuroimaging study involving 20 male M.D. candidates in the middle of preparing for their board exams has found that they had a harder time shifting their attention from one task to another after a month of stress than other healthy young men who were not under stress. The finding replicates what has been found in rat studies, and similarly correlates with impaired function in an area of the prefrontal cortex that is involved in attention. However, the brains recovered their function within a month of the end of the stressful period.

Liston, C., McEwen, B. S., & Casey, B. J. (2009). Psychosocial stress reversibly disrupts prefrontal processing and attentional control. Proceedings of the National Academy of Sciences, 106(3), 912-917. Retrieved from http://www.pnas.org/content/106/3/912.abstract

Full text available at http://www.pnas.org/content/106/3/912.abstract
http://www.eurekalert.org/pub_releases/2009-01/ru-sdh012709.php

Asymmetrical brains let fish multitask

A fish study provides support for a theory that lateralized brains allow animals to better handle multiple activities, explaining why vertebrate brains evolved to function asymmetrically. The minnow study found that nonlateralized minnows were as good as those bred to be lateralized (enabling it to favor one or other eye) at catching shrimp. However, when the minnows also had to look out for a sunfish (a minnow predator), the nonlateralized minnows took nearly twice as long to catch 10 shrimp as the lateralized fish.

Dadda, M., & Bisazza, A. (2006). Does brain asymmetry allow efficient performance of simultaneous tasks? Animal Behaviour, 72(3), 523-529. Retrieved from http://www.sciencedirect.com/science/article/B6W9W-4K716CB-4/2/5ce85e51f001dbef0ad8bb1b37361351

http://sciencenow.sciencemag.org/cgi/content/full/2006/623/2?etoc

How much can your mind keep track of?

A recent study has tried a new take on measuring how much a person can keep track of. It's difficult to measure the limits of processing capacity because most people automatically break down large complex problems into small, manageable chunks. To keep people from doing this, therefore, researchers created problems the test subjects wouldn’t be familiar with. 30 academics were presented with incomplete verbal descriptions of statistical interactions between fictitious variables, with an accompanying set of graphs that represented the interactions. It was found that, as the problems got more complex, participants performed less well and were less confident. They were significantly less able to accurately solve the problems involving four-way interactions than the ones involving three-way interactions, and were completely incapable of solving problems with five-way interactions. The researchers concluded that we cannot process more than four variables at a time (and at that, four is a strain).

Halford, G. S., Baker, R., McCredden, J. E., & Bain, J. D. (2005). How many variables can humans process? Psychological Science: A Journal of the American Psychological Society APS, 16(1), 70-76. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15660854

http://www.eurekalert.org/pub_releases/2005-03/aps-hmc030805.php

We weren't made to multitask

A new imaging study supports the view that we can’t perform two tasks at once, rather, the tasks must wait their turn — queuing up for their turn at processing.

Jiang, Y., Saxe, R., & Kanwisher, N. (2004). Functional magnetic resonance imaging provides new constraints on theories of the psychological refractory period. Psychological Science: A Journal of the American Psychological Society APS, 15(6), 390-396. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15147492

http://www.eurekalert.org/pub_releases/2004-06/aps-wwm060704.php

Why multitasking is a problem

Talking, walking and driving with cell phone users

Another cellphone-multitasking study! Compared with people walking alone, in pairs, or listening to their ipod, cell phone users were the group most prone to oblivious behavior: only 25% of them noticed a unicycling clown passing them on the street, compared to 51% of single individuals, 61% of music player users, and 71% of people in pairs. In fact, cell phone users even had problems walking — walking more slowly, changing direction more often, being prone to weaving, and acknowledging other people more rarely.

Hyman, I.E.Jr, Boss, S. M., Wise, B. M., McKenzie, K. E., & Caggiano, J. M. (2009). Did you see the unicycling clown? Inattentional blindness while walking and talking on a cell phone. Applied Cognitive Psychology, 9999(9999), n/a. doi: 10.1002/acp.1638.

http://www.eurekalert.org/pub_releases/2009-10/w-tuc101909.php

Chronic media multitasking correlated with poor attention

Media multitasking — keeping tabs on email, texts, IM chat, the web — is routine among young people in particular. We know that humans can’t really multitask very successfully — that what we do is switch tracks, and every time we do that there’s a cost, in terms of your efficiency at the task. But what about long-term costs of chronic multitasking? A study that selected 19 students who multitasked the most and 22 who multitasked least, from a pool of 262 students, found those who multitasked least performed better on three cognitive tests that are thought to reflect ability to ignore distracting information, ability to organize things in working memory, and ability to switch between tasks. The findings can’t answer whether chronic media multitasking reduces these abilities, or whether people who are poor at these skills are more likely to succumb to chronic media multitasking, but they do demonstrate that chronic media multitasking is associated with this particular information processing style.

Ophir, E., Nass, C., & Wagner, A. D. (2009). From the Cover: Cognitive control in media multitaskers. Proceedings of the National Academy of Sciences, 106(37), 15583-15587. Retrieved from http://www.pnas.org/content/early/2009/08/21/0903620106.abstract

http://www.wired.com/wiredscience/2009/08/multitasking/

Cell phone ringtones can pose major distraction, impair recall

Cell phones ringing during a concert is not simply irritating. It appears that in a classroom, a cell phone left to ring for 30 seconds significantly affected the students’ recall for the information presented just prior to and during the ringing. The effect was even greater when the phone’s owner rummaged frantically through her bag. Ringtones that are popular songs were even greater distractions. However, with repeated trials, people could be trained to reduce the negative effects; being warned about the distracting effects also helped people be less affected.

Shelton, J. T., Elliott, E. M., Eaves, S. D., & Exner, A. L. (2009). The distracting effects of a ringing cell phone: An investigation of the laboratory and the classroom setting. Journal of Environmental Psychology, 29(4), 513-521. Retrieved from http://www.sciencedirect.com/science/article/B6WJ8-4VVR204-1/2/280d2689142592e312ee38600103ff4d

http://www.eurekalert.org/pub_releases/2009-06/wuis-cpr060209.php

Police with higher multitasking abilities less likely to shoot unarmed persons

In a study in which police officers watched a video of an officer-involved shooting that resulted in the death of the officer before participating in a computer-based simulation where they were required to make split-second decisions whether to shoot or not to shoot someone, based on slides showing a person holding either a gun or a harmless object like a cell phone, it was found that among those more stressed by the video, those with a lower working memory capacity were more likely to shoot unarmed people. Working memory capacity was not a significant factor for those who did not show heightened negative emotionality in response to the video.

Kleider, H. M., Parrott, D. J., & King, T. Z. (2009). Shooting behaviour: How working memory and negative emotionality influence police officer shoot decisions. Applied Cognitive Psychology, 9999(9999), n/a - n/a. Retrieved from http://dx.doi.org/10.1002/acp.1580

http://www.eurekalert.org/pub_releases/2009-03/gsu-pwh033009.php

Switchboard in the brain helps us learn and remember at the same time

It’s very common that we are required to both process new information while simultaneously recalling old information, as in conversation we are paying attention to what the other person is saying while preparing our own reply. A new study confirms what has been theorized: that there is a bottleneck in our memory system preventing us from doing both simultaneously. Moreover, the study provides evidence that a specific region in the left prefrontal cortex can resolve the bottleneck, possibly by allowing rapid switching between learning and remembering. This is supported by earlier findings that patients with damage to this area have problems in rapidly adapting to new situations and tend to persevere in old rules. The same region is also affected in older adults.

Huijbers, W., Pennartz, C. M., Cabeza, R., & Daselaar, S. M. (2009). When Learning and Remembering Compete: A Functional MRI Study. PLoS Biol, 7(1), e1000011 - e1000011. Retrieved from http://dx.doi.org/10.1371/journal.pbio.1000011

Full text is available at http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.1000011
http://www.eurekalert.org/pub_releases/2009-01/plos-sit010909.php

Neural bottleneck found that thwarts multi-tasking

An imaging study has revealed just why we can’t do two things at once. The bottleneck appears to occur at the lateral frontal and prefrontal cortex and the superior frontal cortex. Both areas are known to play a critical role in cognitive control. These brain regions responded to tasks irrespective of the senses involved, and could be seen to 'queue' neural activity — that is, a response to the second task was postponed until the response to the first was completed. Such queuing occurred when two tasks were presented within 300 milliseconds of each other, but not when the time gap was longer.

Dux, P. E., Ivanoff, J., Asplund, C. L., & Marois, R. (2006). Isolation of a Central Bottleneck of Information Processing with Time-Resolved fMRI. Neuron, 52(6), 1109-1120. Retrieved from http://www.cell.com/neuron/abstract/S0896-6273(06)00903-2

http://www.eurekalert.org/pub_releases/2007-01/vu-nbf011807.php

How multitasking impedes learning

A number of studies have come out in recent years demonstrating that the human brain can’t really do two things at once, and that when we do attempt to do so, performance is impaired. A new imaging study provides evidence that we tend to use a less efficient means of learning when distracted by another task. In the study, 14 younger adults (in their twenties) learned a simple classification task by trial-and-error. For one set of the cards, they also had to keep a running mental count of high tones that they heard while learning the classification task. Imaging revealed that different brain regions were used for learning depending on whether the participants were distracted by the other task or not — the hippocampus was involved in the single-task learning, but not in the dual-task, when the striatum (a region implicated in procedural and habit learning) was active. Although the ability of the participants to learn didn’t appear to be affected at the time, the distraction did reduce the participants' subsequent knowledge about the task during a follow-up session. In particular, on the task learned with the distraction, participants could not extrapolate from what they had learned.

Foerde, K., Knowlton, B. J., & Poldrack, R. A. (2006). Modulation of competing memory systems by distraction. Proceedings of the National Academy of Sciences, 103(31), 11778-11783. Retrieved from http://www.pnas.org/content/103/31/11778.abstract

http://www.sciencedaily.com/releases/2006/07/060726083302.htm

Doing two things at once

Confirmation of what many of us know, and many more try to deny - you can't do two complex tasks simultaneously as well as you could do either one alone. Previous research has showed that when a single area of the brain, like the visual cortex, has to do two things at once, like tracking two objects, there is less brain activation than occurs when it watches one thing at a time. This new study sought to find out whether something similar happened when two highly independent tasks, carried out in very different parts of the brain, were done concurrently. The two tasks used were language comprehension (carried out in the temporal lobe), and mental rotation (carried out in the parietal lobe). The language task alone activated 37 voxels of brain tissue. The mental rotation task alone also activated 37 voxels. But when both tasks were done at the same time, only 42 voxels were activated, rather than the sum of the two (74). While overall accuracy did not suffer, each task took longer to perform.

Just, M. A., Carpenter, P. A., Keller, T. A., Emery, L., Zajac, H., & Thulborn, K. R. (2001). Interdependence of Nonoverlapping Cortical Systems in Dual Cognitive Tasks. NeuroImage, 14(2), 417-426. Retrieved from http://www.sciencedirect.com/science/article/pii/S1053811901908262

http://www.nytimes.com/2001/07/31/health/anatomy/31BRAI.html

The costs of multitasking

Technology increasingly tempts people to do more than one thing (and increasingly, more than one complicated thing) at a time. New scientific studies reveal the hidden costs of multitasking. In a study that looked at the amounts of time lost when people switched repeatedly between two tasks of varying complexity and familiarity, it was found that for all types of tasks, subjects lost time when they had to switch from one task to another, and time costs increased with the complexity of the tasks, so it took significantly longer to switch between more complex tasks. Time costs also were greater when subjects switched to tasks that were relatively unfamiliar. They got "up to speed" faster when they switched to tasks they knew better. These results suggest that executive control involves two distinct, complementary stages: goal shifting ("I want to do this now instead of that") and rule activation ("I'm turning off the rules for that and turning on the rules for this").

Rubinstein, J. S., Meyer, D. E., & Evans, J. E. (2001). Executive Control of Cognitive Processes in Task Switching,. Journal of Experimental Psychology: Human Perception and Performance, 27(4), 763-797. Retrieved from http://www.sciencedirect.com/science/article/B6X08-46FMVFX-N/2/0be000ab7547347baabc95ade3eca37b

http://www.apa.org/journals/xhp/press_releases/august_2001/xhp274763.html

Brain's halves compete for attention

Claus Hilgetag, of Boston University, and his colleagues fired focused magnetic pulses through healthy subjects' skulls for 10 minutes to induce 'hemispatial neglect'. This condition, involving damage to one side of the brain, leaves patients unaware of objects in the opposite half of their visual field (which sends messages to the damaged half of the brain). The subjects showed the traditional symptoms of hemispatial neglect. They were worse at detecting objects opposite to the numb side of their brain, and worse still if there was also an object in the functioning half of the visual field. Yet numbed subjects were better at spotting objects with the unaffected half of their brains. This behavior confirms the idea that activity in one half of the brain usually eclipses that in the opposite half. The finding supports the idea that mental activity is a tussle between the brain's many different areas.

Hilgetag, C. C., Theoret, H., & Pascual-Leone, A. (2001). Enhanced visual spatial attention ipsilateral to rTMS-induced ’virtual lesions’ of human parietal cortex. Nat Neurosci, 4(9), 953-957. Retrieved from http://dx.doi.org/10.1038/nn0901-953

http://www.nature.com/nsu/010830/010830-5.html

Multitasking and driving

Why cell phones and driving don't mix

A host of studies have come out in recent years demonstrating that multitasking impairs performance and talking on a cell phone while driving a car is a bad idea. A new study helps explain why. In two different experiments, subjects were found to be four times more distracted while preparing to speak or speaking than when they were listening. The researcher expects the effect to be even stronger in real-life conversation. It was also found that subjects could complete the visual task in front of them more easily when the projected voice also was in front. This suggests that it may be easier to have all things that require attention in the same space.

Almor, A. (2008). Why Does Language Interfere with Vision-Based Tasks? Experimental Psychology (formerly "Zeitschrift Für Experimentelle Psychologie"), 55(4), 260-268. Retrieved from http://www.psycontent.com/content/827305l337wn25k5/?p=1a1dc47219514daea8f7989c35a2a045&pi=5

http://www.sciencedaily.com/releases/2008/05/080531084958.htm

Talking on a cellphone while driving as bad as drinking

Yet another study has come out rubbing it in that multitasking comes with a cost, and most particularly, that you shouldn’t do anything else while driving. This study demonstrates — shockingly — that drivers are actually worse off when using a cell phone than when legally drunk. The study had 40 volunteers use a driving simulator under 4 different conditions: once while legally intoxicated, once while talking on a hands-free cell phone, once while talking on a hand-held cell phone, and once with no distractions. There were differences in behavior —drunk drivers were more aggressive, tailgated more, and hit the brake pedal harder; cell phone drivers (whether hands-free and hand-held ) took longer to hit the brakes, and got in more accidents. But in both cases drivers were significantly impaired.

Strayer, D. L., Drews, F. A., & Crouch, D. J. (2006). A Comparison of the Cell Phone Driver and the Drunk Driver. Human Factors: The Journal of the Human Factors and Ergonomics Society, 48(2), 381-391. Retrieved from http://hfs.sagepub.com/cgi/content/abstract/48/2/381

http://www.sciencentral.com/articles/view.htm3?article_id=218392815
http://www.eurekalert.org/pub_releases/2006-06/uou-doc062306.php
http://www.guardian.co.uk/mobile/article/0,,1809549,00.html

Performing even easy tasks impairs driving

In yet another demonstration that driving is impaired when doing anything else, a simulator study has found that students following a lead car and instructed to brake as soon as they saw the illumination of the lead car's brake lights, responded slower when required to respond to a concurrent easy task, where a stimulus - either a light flash in the lead car's rear window or an auditory tone - was randomly presented once or twice and participants had to indicate the stimulus' frequency. The finding suggests that even using a hands-free device doesn’t make it okay to talk on a cell phone while driving.

Levy, J., Pashler, H., & Boer, E. (2006). Central interference in driving: is there any stopping the psychological refractory period? Psychological Science: A Journal of the American Psychological Society APS, 17(3), 228-235. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/16507063

http://www.psychologicalscience.org/media/releases/2006/pr060303.cfm

Talking and listening impairs your ability to drive safely

A study involving almost 100 students driving virtual cars has provided evidence that people have greater difficultly maintaining a fixed speed when performing tasks that simulated conversing on a mobile phone. Both speaking and listening were equally distracting.

Kubose, T. T., Bock, K., Dell, G. S., Garnsey, S. M., Kramer, A. F., & Mayhugh, J. (2006). The effects of speech production and speech comprehension on simulated driving performance. Applied Cognitive Psychology, 20(1), 43-63. Retrieved from http://dx.doi.org/10.1002/acp.1164

http://www.eurekalert.org/pub_releases/2005-08/jws-cpu082205.php

Cell phone users drive like seniors

Another study on the evils of multitasking, in particular, of talking on a cellphone while driving. This one has a nice spin — the study found that when young motorists talk on cell phones, they drive like elderly people, moving and reacting more slowly and increasing their risk of accidents. Specifically, when 18- to 25-year-olds were placed in a driving simulator and talked on a cellular phone, they reacted to brake lights from a car in front of them as slowly as 65- to 74-year-olds who were not using a cell phone. Although elderly drivers became even slower to react to brake lights when they spoke on a cell phone, they were not as badly affected as had been expected. An earlier study by the same researchers found that motorists who talk on cell phones are more impaired than drunken drivers with blood alcohol levels exceeding 0.08.

Strayer, D. L., & Drew, F. A. (2004). Profiles in Driver Distraction: Effects of Cell Phone Conversations on Younger and Older Drivers. Human Factors: The Journal of the Human Factors and Ergonomics Society, 46(4), 640-649. Retrieved from http://hfs.sagepub.com/cgi/content/abstract/46/4/640

http://www.eurekalert.org/pub_releases/2005-02/uou-cpu020105.php

Complex mental tasks interfere with drivers' ability to detect visual targets

The researchers studied 12 adults who drove for about four hours on the highway north from Madrid. During the journey, drivers listened to recorded audio messages with either abstract or concrete information (acquisition task), and later were required to freely generate a reproduction of what they had just listened to (production task). Although the more receptive tasks – listening and learning -- had little or no effect on performance, there were significant differences in almost all of the measures of attention when drivers had to reproduce the content of the audio message they had just heard. Drivers also performed other tasks, either live or by phone. One was mental calculus (mentally changing between Euros and Spanish pesetas) either with an experimenter in the car, talking to the driver, or with the driver speaking by hands-free phone. One was a memory task (giving detailed information about where they were and what they were doing at a given day and time). Both tasks significantly impacted on the driver's ability to detect visual targets. In the experimental variation that examined the impact of hands-free phone conversation, message complexity made the difference. The relative safety of low-demand phone conversation -- if hands-free and voice-operated --appeared to be about the same as that of live conversation. The findings also confirm that the risk of internal distraction (one’s own thoughts) is at least as relevant as external distraction.

Goldarecena, M.A.R. & González, L.M.N. 2003. Mental Workload While Driving: Effects on Visual Search, Discrimination and Decision Making. Journal of Experimental Psychology: Applied, 9(2)

http://www.eurekalert.org/pub_releases/2003-06/apa-mcm062403.php

Why multitasking is more difficult with age

Comparison of young adults (mean age 24.5) and older adults (mean age 69.1) in a visual memory test involving multitasking has pinpointed the greater problems older adults have with multitasking. The study involved participants viewing a natural scene and maintaining it in mind for 14.4 seconds. In the middle of the maintenance period, an image of a face popped up and participants were asked to determine its sex and age. They were then asked to recall the original scene.

Older adults have better implicit memory

A study involving 125 younger (average age 19) and older (average age 69) adults has revealed that while younger adults showed better explicit learning, older adults were better at implicit learning. Implicit memory is our unconscious memory, which influences behavior without our awareness.