97.5% Can't Drive Safely While Using Cell Phones
Braking Time Slowed, Memory Waned When Drivers Used Cell Phones; Only a Small Percentage of 'Supertaskers' Were Successful
March 31, 2010 -- Driving while talking on a cell phone is extremely
hazardous for most people, and only a tiny fraction of “supertaskers” can do
both simultaneously without any ill effect, a new study says.
University of Utah psychologists found that only 2.5% of people they studied
could successfully drive and use a cell phone at the same time. Most people --
97.5% -- aren’t able to drive like they should if they’re talking on a cell
phone, researchers say.
The findings don’t mean that supertaskers are smarter than most folks, but
probably that genetic factors are at play, making some people better able to do
two or more things at once, one of the study authors, Dave Strayer, PhD, tells
“We were excited to find this small group of people with extraordinary
multitasking ability,” Strayer says. “We hope comparing them with the rest of
us will help us better understand how the brain coordinates multitasking.”
Co-author James Watson, PhD, says they used the term “supertasker” to
describe multitasking ability. He says the odds are “overwhelmingly against”
most people being multitaskers -- “about as good as your chances of flipping a
coin and getting five heads in a row.”
The researchers analyzed the performance of 200 participants over a single
task -- driving a simulated car on a virtual freeway. Then the same people got
behind the wheel and were assigned a second, demanding activity -- a cell phone
conversation that involved them memorizing words and solving math problems.
Watson and Strayer measured performance of the participants in four areas --
braking reaction time, following distance, memory, and ability to solve the
Results showed that for most people in the group, performance suffered
across the board when they drove while talking on a hands-free cell phone.
It took most people 20% longer to hit the brakes and increased
following distances 30%, meaning they failed to keep pace in the simulator with
virtual traffic. Also, their memory performance dropped 11% and their ability
to do the math fell 3%.
But for a few, it was all a snap. They displayed no change in normal braking
times, following distances, or math ability, and memory actually improved 3%,
the researchers say.
The findings are published in the journal Psychonomic Bulletin and
The researchers say the results were in line with Strayer’s previous studies
showing that driving performance routinely declines when people talk on cell
phones, even to the point of being on a par with the impairment seen in drunken
Yet the supertaskers managed just fine.
The Study of Supertaskers
Watson and Strayer have collected brain scan data (by functional magnetic
resonance imaging) on all participants and hope to get a better understanding
of brain differences that might explain why a few people can multitask while