The people who multitask the most are the ones who are worst at it.
That is the surprising conclusion of researchers at Stanford University, who found multitaskers are more easily distracted and less able to ignore irrelevant information than people who do less multitasking.
The researchers studied 262 college undergraduates, dividing them into high and low multitasking groups and comparing such things as memory, ability to switch from one task to another and being able to focus on a task. Their findings are reported in Tuesday's edition of Proceedings of the National Academy of Sciences.
When it came to such essential abilities, people who did a lot of multitasking didn't score as well as others.
Still to be answered is why the folks who are worst at multitasking are the ones doing it the most.
In the study, the researchers first had to figure out who are the heavy and light multitaskers. They gave the students a form listing a variety of media such as print, television, computer-based video, music, computer games, telephone voice or text, and so forth.
The students were asked, for each form of media, which other forms they used at the same time always, often, sometimes or never. The result ranged from an average of about 1.5 media items at the low end to more than four among heavy multitaskers.
Then they tested the abilities of students in the various groups.
For example, ability to ignore irrelevant information was tested by showing them a group of red and blue rectangles, blanking them out, and then showing them again and asking if any of the red ones had moved.
The test required ignoring the blue rectangles. The researchers thought people who do a lot of multitasking would be better at it.
But they're not. They're worse. They're much worse. The high media multitaskers couldn't ignore the blue rectangles. They couldn't ignore stuff that doesn't matter.
Perhaps the multitaskers can take in the information and organize it better? Nope.
They are worse at that, too.
OK, maybe they have bigger memories. But that is not the case either.
Finally, researchers tested ability to switch from one task to another by classifying a letter as a vowel or consonant, or a number as even or odd. The high multitaskers took longer to make the switch from one task to the other.