For years, people have been saying that kids who excel at multitasking–juggling a variety of activities at one time, such as doing homework while participating in an online chat–have an advantage over kids who don’t. Now a new study says that while doing multiple tasks at once may appear to be more efficient, it can actually be more time-consuming and less healthy.

Researchers at the Federal Aviation Administration (FAA) and the University of Michigan reached that conclusion by studying four groups of young adults who participated in a series of experiments.

The students alternated between performing the same task repeatedly and performing a number of different tasks. The activities ranged from complicated tasks, such as solving a math problem, to easier and more familiar tasks, such as identifying a geometric shape. A participant’s performance speed was measured as the tasks were carried out.

The researchers found that the capacity for multitasking in humans is limited. The study showed participants lost time in performance speed when switching tasks and they lost more time as the task became more complex.

The study was published in the August issue of the Journal of Experimental Psychology: Human Perception and Performance, an American Psychological Association publication. Its implications may have a significant impact on a younger generation that has become adept at jumping among eMail, word processing, and a variety of school subjects.

“It seems multitasking is becoming more prevalent … We are doing more and more with computers, and the nature of the computer is to be able to switch back and forth among applications frequently,” said Dr. Joshua S. Rubinstein, an engineering research psychologist with the FAA and one of the report’s authors. “I’d say it is both technology and economy that are driving multitasking.”

But according to Rubinstein, the study shows that when students are switching back and forth rather than concentrating on one task at a time they will be less efficient, learn the material more slowly, and be more likely to make errors.

That’s because when people switch from one activity to another–from surfing the internet to chatting on a cell phone, for instance–they are using different areas of the brain. Switching from one part of the brain to another can take very small amounts of time (called the “switching-cost”). Those small time fragments add up in the long run.

A number of experts have begun to voice concern about the level of task-switching expected of students in so-called “digital schools.”

“I fear…we’re raising a whole generation of kids who will be so addicted to the thrill of multitasking that as they grow older we’ll see this huge communal sacrifice of some of the qualities we hold dear, like patience and tranquility,” said David Shenk, author of Datasmog: Surviving the Information Glut, in a New York Times interview. “Restlessness will triumph over all.”

Although there has been little research on the psychological implications of long-term multitasking, the issue is gaining more attention, especially among behavioral scientists and educators.

“You have to be able to task effectively before you can multitask effectively,” Dr. Jane M. Healy told the New York Times. Healy is an educational psychologist and author of Failure to Connect: How Computers Affect Our Children’s Minds, and What We Can Do About It. “I think the piece we’re missing with today’s kids is to stick with one thing … and be effective at it.”

Researchers believe multitasking may hold the potential for health-related problems as well. “There’s more frustration and mental exhaustion from switching back and forth,” said Rubinstein. That may lead to a higher level of stress among students. “On the other hand, some may claim that it makes working less monotonous–we haven’t looked at that.”

Anecdotally, Rubinstein says there appears to be a tradeoff “between doing things well and being constantly stimulated. … However, if the future will demand multitasking, maybe students need to get used to doing it.”

In fact, given the high demand for multitasking in our increasingly digital world, some people believe educators should teach this skill to kids.

“Even if it is less efficient, that may be the world they are walking into,” Rubinstein said. “It’s a tough question: How do you train kids–to do things well or to fit into a society that requires constant stimulation?”

Links:

Journal of Experimental Psychology: Human Perception and Performance
http://www.apa.org/journals/xhp.html

Federal Aviation Administration
http://www.faa.gov

University of Michigan
http://www.umich.edu