“To do two things at once is to do neither.”
Publilius Syrus, Roman slave, first century B.C.

We’ve all heard the woes of students who start their homework after dinner and are still going strong at midnight. But are they truly working nonstop or are they getting distracted along the way? Does the computer that was switched on for research also display instant messages? Email? Facebook? If so, two hours of work can easily stretch into six.

While many people brag about their ability to multi-task or switch-task, it turns out that none of us, kids included, perform well when interrupted. That’s because our brains can only focus on one item at a time. In this age of tweets, texting, and social networking, the interruptions fly nonstop. We may be able to walk and talk at the same time, but when it comes to paying attention, our brains have limits.

But what about those who insist they’re wired for multitasking? Stanford researchers decided to find out what gives these folks their edge. What gift do they have that the rest of us inefficient, single-taskers are missing? “We kept looking for what they’re better at, and we didn’t find it,” said Eyal Ophir, the study’s lead author. In fact, they found that multitaskers pay a mental price, and in some cases perform worse than non-multitaskers, People who are regularly bombarded with several streams of electronic information do not pay attention, control their memory or switch from one job to another as well as those who prefer to complete one task at a time.

Other task-switching research shows that doing more really means doing less. Dr. John Medina, author of Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School, explains that the part of our brain responsible for switching activities, what he calls the “attentional spotlight,” works as a sequential processor. This means, it can only focus on one task at a time. He claims that a person who is interrupted takes 50% longer to complete a task and makes 50% more errors. He shared the following anecdote, which may hit a little too close to home for many of today’s parents:

“Recently, I agreed to help the high-school son of a friend of mine with some homework, and I don’t think I will ever forget the experience. Eric had been working for about a half-hour on his laptop when I was ushered to his room. An iPod was dangling from his neck, the earbuds cranking out Tom Petty, Bob Dylan, and Green Day as his left hand reflexively tapped the backbeat. The laptop had at least 11 windows open, including two IM screens carrying simultaneous conversations with MySpace friends. Another window was busy downloading an image from Google. The window behind it had the results of some graphic he was altering for MySpace friend No. 2, and the one behind that held an old Pong game paused mid-ping. Buried in the middle of this activity was a word-processing program holding the contents of the paper for which I was to provide assistance. ‘The music helps me concentrate,’ Eric declared, taking a call on his cell phone.”

The task-switching problem is not limited to students. Workplace studies indicate that performing several duties at once reduces employee productivity. University of Michigan researcher David Meyer, Ph.D. [pdf], explains that in work settings, 20-40 percent of potential efficiency is lost due to task switching by workers “who are banging away on word processors at the same time they have to answer phones and talk to their co-workers or bosses.” Researchers at the University of California at Irvine found that workers returning to a task took an average of 23 minutes and 15 seconds to recover from interruptions and displayed significantly higher levels of stress, frustration, and mental effort.

Multitasking has also been shown to adversely affect how people learn. An article in The New Atlantis points to Russell Poldrack, a psychology professor at the University of California, Los Angeles, who found “that even if you learn while multitasking, that learning is less flexible and more specialized, so you cannot retrieve the information as easily.” Poldrack’s research demonstrates that people use different areas of the brain for learning and storing new information when they are distracted: brain scans of people who are distracted or multitasking show activity in the striatum, a region of the brain involved in learning new skills; brain scans of people who are not distracted show activity in the hippocampus, a region involved in storing and recalling information.

The solution for students who want to learn the lost art of paying attention is to focus on the task at hand. Turn off the distractions, make a plan, and concentrate on one activity at a time. Then reward yourself by powering back up. When done well, you’ll spend less overall time on your work, learn more, and have plenty of time leftover for fun.