By Craig Weatherby
Some folks take pride in their multitasking habit, seeing it as a badge of modernity, diligence, and efficiency.
But growing evidence – including distressing data from a new study – further undermines the idea that multitasking aids efficiency or productivity.
For example, in 2009 Stanford University scientists found that switching repeatedly among tasks was counterproductive … see “Multitaskers May Pay a Big Performance Price”.
Last year, researchers from New York City’s Weill Cornell Medical Center performed an evidence review and came to a similar conclusion:
“Multitasking is … rarely as successful as its proponents believe … overuse or misuse of personal electronic devices promotes cognitive overload … and lowers performance at all ages ...” (Weksler ME, Weksler BB 2012)
Practice can make multitasking less damaging to performance … but such training rarely happens in real-word settings (Dux PE et al. 2009).
Now, a new study from the University of Utah indicates that the people who multitask the most – including talking on a cell phone while driving – are the worst at it.
“We showed that people who multitask the most are those who appear to be the least capable of multitasking effectively,” said senior author and psychology Professor David Sanbonmatsu (UU 2013).
Co-author and psychology Professor David Strayer, added, “The people who are most likely to multitask harbor the illusion they are better than average at it, when in fact they are no better than average and often worse.” (UU 2013)
Dr. Sanbonmatsu highlighted their most disturbing finding: “What is alarming is that people who talk on cells phones while driving tend to be the people least able to multitask well.” (UU 2013)
What the study showed
The study authors recruited 310 undergraduate psychology students – 176 women and 134 men (Sanbonmatsu DM et al. 2013).
The student volunteers performed a battery of tests and questionnaires intended to measure several things:
Actual multitasking ability
Cell phone use while driving
Perceived multitasking ability
Use of a wide array of electronic media Personality traits such as impulsivity and sensation-seeking.
After analyzing the results, the author reported these key findings:
Those most capable of multitasking effectively were not the volunteers who were most likely to engage in multiple tasks simultaneously.
People who score high on a test of actual multitasking ability tend not to multitask and are better able to focus attention on the task at hand.
- The more people multitask, the more they lack the actual ability to multitask, and their self-perceived ability was significantly inflated.
People with high levels of impulsivity and sensation-seeking reported more multitasking.
- People who engage in multitasking are less able to block distractions and focus on a singular task.
Study participants reported spending 13 percent of their driving time talking on a cell phone … and the U.S. government estimates that one in 10 drivers are on the phone at any given time.
The researchers came to a logical conclusion regarding phone-talking while driving: “The negative relation between cellular communication while driving and multitasking ability appears to further bolster arguments for legislation limiting the use of cell phones while operating a motor vehicle.” (UU 2013)
Who multitasks and why?
“The people who multitask the most tend to be impulsive, sensation-seeking, [and] overconfident of their multitasking abilities, and they tend to be less capable of multitasking,” said Dr. Strayer (UU 2013).
And as Dr. Sanbonmatsu said, the 25 percent of the people who performed best on the test of multitasking ability “are the people who are least likely to multitask and are most likely to do one thing at a time.” (UU 2013)
In contrast, the 70 percent of participants who said they were above-average at multitasking were more likely to multitask.
“One of the main reasons people multitask is because they think they are good at it,” Sanbonmatsu said. “But our study suggests people rarely are as good at multitasking as they think they are.” (UU 2013)
Multitasking – including cell phone use while driving – correlated significantly with sensation-seeking.
This suggests that some people multitask because it is more stimulating, interesting and challenging, and less boring – even if it may hurt their overall performance.
Media multitasking – except cell phone use while driving – correlated significantly with impulsivity, particularly the inability to concentrate and acting without thinking.
Impulsive people tend to be more reward-oriented and more apt to take risks, so they may be less sensitive to the costs of multitasking, the researchers said.
The study (Sanbonmatsu DM et al. 2013) was funded by the American Automobile Association Foundation for Traffic Safety.
Dux PE, Tombu MN, Harrison S, Rogers BP, Tong F, Marois R. Training improves multitasking performance by increasing the speed of information processing in human prefrontal cortex. Neuron. 2009 Jul 16;63(1):127-38.
Gorlick A. Media multitaskers pay mental price, Stanford study shows. Stanford Report, August 24, 2009. Accessed at http://news.stanford.edu/news/2009/august24/multitask-research-study-082409.html
Klingberg T. Limitations in information processing in the human brain: neuroimaging of dual task performance and working memory tasks. Prog Brain Res. 2000;126:95-102. Review.
Meyer D, Kieras D. Multitasking and Task Switching. Accessed at http://www.umich.edu/~bcalab/multitasking.html Ophir E, Nass C, Wagner AD. Cognitive control in media multitaskers. Proc Natl Acad Sci U S A. 2009 Aug 24. [Epub ahead of print] doi:10.1073/pnas.0903620106. Accessed at http://www.pnas.org/content/early/2009/08/21/0903620106.abstract
Ruthruff E, Johnston JC, Van Selst M, Whitsell S, Remington R. Vanishing dual-task interference after practice: has the bottleneck been eliminated or is it merely latent? J Exp Psychol Hum Percept Perform. 2003 Apr;29(2):280-9.
Sanbonmatsu DM, Strayer DL, Medeiros-Ward N, Watson JM. (2013) Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking. PLoS ONE 8(1): e54402. doi:10.1371/journal.pone.0054402. Accessed at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0054402
Sigman M, Dehaene S. Brain mechanisms of serial and parallel processing during dual-task performance. J Neurosci. 2008 Jul 23;28(30):7585-98. doi: 10.1523/JNEUROSCI.0948-08.2008.
Szameitat AJ, Lepsien J, von Cramon DY, Sterr A, Schubert T. Task-order coordination in dual-task performance and the lateral prefrontal cortex: an event-related fMRI study. Psychol Res. 2006 Nov;70(6):541-52. Epub 2005 Sep 2.
University of Utah (UU). Frequent Multitaskers Are Bad at It. January 23, 2013. Accessed at http://unews.utah.edu/news_releases/frequent-mulitaskers-are-bad-at-it/