Half a decade ago I noted here a New York Times report on the myth of multitasking. The topic resurfaced on 30 August in Ruth Pennebaker's "The Mediocre Multitasker":

Last week, researchers at Stanford University published a study showing that the most persistent multitaskers perform badly in a variety of tasks. They don't focus as well as non-multitaskers. They're more distractible. They're weaker at shifting from one task to another and at organizing information. They are, as a matter of fact, worse at multitasking than people who don't ordinarily multitask.

After a bit of cheerfully humorous gloating Pennebaker shares comments from the authors:

"Multitaskers were just lousy at everything," said Clifford I. Nass, a professor of communication at Stanford and one of the study's investigators. "It was a complete and total shock to me."

Initially suspecting that multitaskers possessed some rare and enviable qualities that helped them process simultaneous channels of information, Professor Nass had been "in awe of them," he said, acknowledging that he himself is "dreadful" at multitasking. "I was sure they had some secret ability. But it turns out that high multitaskers are suckers for irrelevancy."

...

Eyal Ophir, the study's lead investigator and a researcher at Stanford's Communication Between Humans and Interactive Media Lab, said: "We kept looking for multitaskers' advantages in this study. But we kept finding only disadvantages. We thought multitaskers were very much in control of information. It turns out, they were just getting it all confused."

The abstract of the article itself is at [1]. Comrade Paul Heller points out "The Myth of Multitasking" in The New Atlantis (Christine Rosen, Spring 2008) which begins with the insightful:

In one of the many letters he wrote to his son in the 1740s, Lord Chesterfield offered the following advice: "There is time enough for everything in the course of the day, if you do but one thing at once, but there is not time enough in the year, if you will do two things at a time." To Chesterfield, singular focus was not merely a practical way to structure one's time; it was a mark of intelligence. "This steady and undissipated attention to one object, is a sure mark of a superior genius; as hurry, bustle, and agitation, are the never-failing symptoms of a weak and frivolous mind."

_{^z - 2009-09-01}