Does Multitasking Make Us Less Productive?

With an ever-rising number of demands on our daily attention, most of us are performing several tasks at once. But does multitasking improve our productivity, or does it actually get in the way of accomplishing tasks?

The quickening pace of business in recent years already made it seem as if those who couldn't handle a tidal wave of work would be left behind. Add to that the number of jobs lost over the past year and half, and it's clear that layoff survivors are swamped with more tasks than ever before.

As a result, many workers turn to multitasking in an attempt to tackle several duties simultaneously. Technology reinforces this tendency, with employees concurrently answering e-mail, searching the Web and taking phone calls, sometimes all on the same device.

However, researchers at Stanford University have concluded that multitasking may actually impede productivity, reducing the quality of our work and the rate at which we accomplish it. Their study, published in the Proceedings of the National Academy of Sciences in August, found that people who divide their efforts between multiple tasks pay less attention, have poorer control over their memory and experience more difficulty switching from one job to another than those who focus on completing one task at a time.

The Stanford University study tested a group of 100 students composed of both "high multitaskers," who regularly use four or more media simultaneously, and "low multitaskers," who engage with no more than two media at a time.

"Results showed that heavy media multitaskers are more susceptible to interference from irrelevant environmental stimuli and from irrelevant representations in memory. This led to the surprising result that heavy media multitaskers performed worse on a test of task-switching ability, likely due to reduced ability to filter out interference from the irrelevant task set," the study explained.

"We were shocked to find out that the high multitaskers did worse than the low multitaskers in all three basic aspects of successful multitasking," Clifford Nass, a communication professor and one of the study's authors, said in a Web Worker Daily report.

The three areas in which non-multitaskers excelled: 1) the ability to focus on relevant information while ignoring irrelevancies, 2) keeping information organized within the brain and 3) the amount of time necessary to mentally switch between multiple tasks.

Although many people assume that those who multitask successfully must have a great deal of control over how they direct their thoughts, the Stanford research team found that this is usually not the case.

"We kept looking for what they're better at, and we didn't find it," Eyal Ophir, a researcher in Stanford's Communication Between Humans and Interactive Media Lab and the study's lead author, said in an announcement of the findings. "They couldn't help thinking about the task they weren't doing. The high multitaskers are always drawing from all the information in front of them. They can't keep things separate in their minds," Ophir added.

Heavy multitaskers generally displayed slower response times to changing conditions, usually because they became more easily distracted by unrelated information or stimuli, which was then stored in their short-term memory, later interfering with their ability to recall pertinent details.

"There are some possibly frightening implications of the study. If it's not very reversible, then the way the culture has become might be pushing us all to become more and more distractible and less and less able to focus over sustained periods of time," Gary Aston-Jones, professor of neuroscience at the Medical University of South Carolina, told

Given the climbing unemployment rate and increasing average productivity in the United States, it stands to reason that fewer workers are handling more responsibilities, and many them are likely multitasking in an effort to keep up their output. The problem is that, if true multitasking is impossible, then workers who attempt to multitask are actually slowing themselves down.

"Multitasking is shifting focus from one task to another in rapid succession. It gives the illusion that we're simultaneously tasking, but we're really not. It's like playing tennis with three balls," Edward M. Hallowell, psychiatrist and author, told the New York Times.

A 2007 report on information technology and its effect on worker productivity highlighted the importance of keeping multitasking at a low level, claiming that "productivity is greatest for small amounts of multitasking but beyond an optimum, multitasking is associated with declining project completion rates and revenue generation."

When confronted with a daunting quantity of work, perhaps it is better to avoid trying to tackle multiple tasks simultaneously, instead focusing on assignments one at a time. This strategy might turn out to be a more effective way to manage a heavy workload, and it will certainly be gentler on the nerves.


Multitasking Terror

Worker Productivity Soars in Third Quarter


Cognitive Control in Media Multitaskers

by Eyal Ophir, Clifford Nass and Anthony D. Wagner

Proceedings of the National Academy of Sciences, Aug. 24, 2009

Does Multitasking Make You More Productive?

by Karen Leland

Web Worker Daily, Nov. 2, 2009

Media Multitaskers Pay Mental Price, Stanford Study Shows

by Adam Gorlick

Stanford University, Aug. 24, 2009

Drop That BlackBerry! Multitasking May Be Harmful

by Theresa Tamkins, Aug. 24, 2009

Multitasking Can Make You Lose ... Um ... Focus

by Alina Tugend

The New York Times, Oct. 24, 2008

Information, Technology and Information Worker Productivity

by Sinan Aral, Erik Brynjolfsson and Marshall W. Van Alstyne

The National Bureau of Economic Research, June 2007

All Topics