Drivers who believe they are skilled at multitasking – such as taking a phone call while on the road – actually are the least likely to be capable of safely doing so, a new study reveals. In fact, drivers who multitask may be inclined to do so because they have difficult focusing closely on even a single task.

Senior authors David Sanbonmatsu, Ph.D., and David Strayer, Ph.D., both psychology professors at the University of Utah, say their new study suggests drivers should not harbor the illusion that they are better than average at multitasking while driving. Citing humorist Garrison Keillor’s catchphrase about kids in Keillor’s fictitious hometown, Strayer said people who use cell phones while driving “all think they live in Lake Wobegon, where everybody is above average. But it’s a statistical impossibility.”

“One of the main reasons people multitask is because they think they are good at it,” Sanbonmatsu explained. “But our study suggests people rarely are as good at multitasking as they think they are.”

Fractured Focus

The study ran 310 undergraduate psychology students through a battery of tests and questionnaires to measure 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. Key findings include:

  • Drivers most capable of multitasking effectively are not those who are most likely to engage in multiple tasks simultaneously. Instead, people who score high on a test of actual multitasking ability tend not to multitask because they are better able to focus attention on the task at hand.
  • The more people multitask by talking on cell phones while driving or by using multiple media at once, the more they lack the actual ability to multitask, and their perceived multitasking ability “was found to be significantly inflated.” In fact, 70 percent of participants thought they were above average at multitasking, which is statistically impossible.
  • People with high levels of impulsivity and sensation-seeking reported more multitasking, with one exception: People who talk on cell phones while driving tend not to be impulsive, indicating that cell phone use is a deliberate choice.
  • The research suggests that people who engage in multitasking often do so not because they have the ability, but “because they are less able to block out distractions and focus on a singular task.”

“If you have people who are multitasking a lot, you might come to the conclusion they are good at multitasking,” Strayer said. “In fact, the more likely they are to do it, the more likely they are to be bad at it.”

The researchers concluded that the study “appears to further bolster arguments for legislation limiting the use of cell phones while operating a motor vehicle.”

Sanbonmatsu and Strayer conducted the study with University of Utah co-authors Jason Watson, an associate professor of psychology, and Nathan Medeiros-Ward, a doctoral student in psychology. The study was funded by the American Automobile Association Foundation for Traffic Safety and was published Jan. 23 in PLOS ONE, an online journal of the Public Library of Science.