SALT LAKE CITY, March 29 (UPI) -- Many think they can multitask, but only 2.5 percent of the population can successfully do two things at the same time, U.S. researchers suggest.
Psychologists Jason Watson and David Strayer of the University of Utah assessed the performance of 200 subjects during simulated freeway driving and a second time during simulated freeway driving while having a cellphone conversation using a hands-free cellphone that involved memorizing words and solving math problems.
When supertaskers talked while driving they had no change in brake time, following distances or doing math problems. Memory improved 3 percent, the researchers found.
The 97.5 percent who are not supertaskers and talked on a cellphone while driving took 20 percent longer to hit the brakes, following distances increased 30 percent, memory performance declined 11 percent and the ability to do math problems declined 3 percent.
"According to cognitive theory, these individuals ought not to exist," Watson says in a statement.
"Yet, clearly they do, so we use the supertasker term as a convenient way to describe their exceptional multitasking ability. Given the number of individuals who routinely talk on the phone while driving, one would have hoped that there would be a greater percentage of supertaskers."
The findings are published in the journal Psychonomic Bulletin and Review.
