STEVE INSKEEP, host:
It is Thursday morning, which is when we take a look at your health. And this morning we'll be looking at multitasking, something that's addictive, but maybe not that healthy. When we do several tasks at once, we can feel amazingly productive. But scientists say usually we are not. And today, NPR's Jon Hamilton continues his look at the human brain when it tries to do too much, too fast.
Mr. ZACH WEINBERG (Student, Bethesda-Chevy Chase High School, Maryland): And it's just an ugly, ugly problem.
JON HAMILTON: Forget Gen X and Gen Y. This is Generation M, M as in multitasking.
Mr. WEINBERG: All right, she just responded. She says, I'm ever so happy.
HAMILTON: Zach Weinberg is a member of this generation. He's also a junior at the Bethesda-Chevy Chase High School in suburban Maryland.
Mr. WEINBERG: Our conversation is not going anywhere.
HAMILTON: It's a school night, so Zach is camped in front of his computer.
Mr. WEINBERG: I have two open windows with people that I've been talking to. Up at the top, smaller, I've got my iTunes, so I can control what song is playing. And off in the corner, I've also got a game where you switch letters around to make words...
HAMILTON: Zach's manages to squeeze in some homework, too.
Mr. WEINBERG: And so if I start out with the problem of negative Y squared plus Y squared is equal to 81. Y squared plus Y squared - it's not good. All right now. Back to Alex, he says...
HAMILTON: Zach has just heard from Alex Donesky, the friend and classmate whose text message is sitting in one of the open windows on his computer. Alex is at his house nearby also doing homework.
Mr. ALEX DONESKY (Student, Bethesda-Chevy High School, Maryland): (French spoken)
HAMILTON: His French assignment is in one corner of his computer screen. That makes it easy for him to click over to Facebook, Google, instant messaging, and music from his favorite band "Fall of Troy."
(Soundbite of music)
Mr. DONESKY: (French spoken)
HAMILTON: Alex pauses every couple of minutes to answer messages from Zach, and says Zach...
Mr. WEINBERG: I'm so happy that we don't have school till 11:30 tomorrow. I think I'll sit in Barnes and Nobles and work with Alyssa(ph)...
HAMILTON: Zach is writing to Alex about a theater project. Anyway, back at his house, Alex is not impressed.
Mr. DONESKY: That is extremely lame.
HAMILTON: And a few seconds later, back to Zach.
Mr. WEINGBERG: That is extremely lame.
HAMILTON: For the record, Alex and Zach are good students. And obviously they're good multitaskers, too. Alex's mom, Barbara Donesky, says she's dazzled by the skill her son has developed.
Ms. BARBARA DONESKY: When we ask him to show us something on the computer, I can't believe the speed of which he sort of clicks around, clicks around, clicks around and makes something happen.
HAMILTON: But she's afraid Alex is losing out on other skills.
Ms. DONESKY: I mean, I want him to be able to concentrate. I want him to be able to focus. I mean, it's my personal belief that all these things just fragment your ability to concentrate. And I see it in myself, you know, since I've started emailing and using the computer very regularly.
HAMILTON: Although, there's not much data yet on teens, scientists say she has reason to be worried. David Meyer at the University of Michigan has spent the past few decades studying multitasking mostly in adults.
Dr. DAVID MEYER (Professor of Psychology, University of Michigan): For tasks that are at all complicated, no matter how good you have become at multitasking, you're still going to suffer hits against your performance. You will be worse compared to if you were actually concentrating from start to finish on the task.
HAMILTON: Multitasking causes a kind of brownout in the brain. Meyer says all the lights go dim because there just isn't enough power to go around.
Mr. DONESKY: Rafael...
HAMILTON: When Alex clicks on a message, his brain starts losing the connections it was using for his French assignment. The pathway to Robespierre is fading fast. The path to les artistes is not so clear anymore.
Mr. DONESKY: (French spoken)
HAMILTON: To restore those connections, researcher David Meyer says Alex will have to repeat much of the thought process that created them in the first place. The technical name for creating or recreating these neural pathways is spreading activation. It involves building connections step by step. Meyer says it's similar to what we do when we free associate.
Dr. MEYER: I say to you, what do you think of when I say the word apple to you? And you start vibing on apple. Oh, apple's a fruit. It fell on Newton's head. Newton was a physicist. He invented the first theory of gravity. And on and on we go.
HAMILTON: When we're interrupted, getting those connections back can take a few seconds or many hours.
Dr. MEYER: It goes on subconsciously, and eventually, if I'm lucky, I get back up to speed with what it was I was thinking about before.
Mr. WEINBERG: Back to the math. Where was I?
HAMILTON: Zach Weinberg, one of our high school students, concedes that multitasking might make him less efficient. But he maintains that in small doses it can help him stay alert, like when he listens to this music and does a math problem at the same time.
Mr. WEINBERG: If I had only one thing, I'd drift off a little bit. But if there's something else going on in the background that I can just sort of block out, I feel that I can concentrate on something more. Whereas if it's just perfectly quiet and I'm only doing one thing, it's harder for me to concentrate.
HAMILTON: Scientists say Zach has a point. Studies show it's pretty easy for us to keep music in the background when we focus on something else. But when something in the background forces itself into your consciousness, you do get distracted, like when you hear that chime telling you an instant message has arrived.
Mr. WEINBERG: But most people learn to get used to that distraction, to know when to give in to it and when to say no, I've got to work, and I'm not going to give into this.
HAMILTON: Saying no to distractions depends in part on being able to control your impulses, something that's not fully developed in a teenager's brain. And Zach's friend Alex Donesky says it's not easy for him. He says it's hard to give your full attention to any one thing when you used to monitoring a screen full of options.
Mr. DONESKY: You're teaching yourself to give, like, 10 percent to each little icon on the screen and then click away when there's a moment's pause.
HAMILTON: In fact, David Meyer the neuroscientist says our brains can get hooked.
Dr. MEYER: They get antsy. They start fidgeting. They literally need a fix of multitasking.
HAMILTON: There's not much research specifically on the addictive nature of multitasking, but Meyer says it's a lot like playing videogames or sky diving. We all get a buzz from novelty and variety. Meyer says he likes to watch a ballgame and read the paper and listen to the radio all at the same time.
Dr. MEYER: I suspect that if you put electrodes into appropriate parts of my brain when I go home and engage in these various kinds of information reception activities all at the same time, I will be feeling good about it.
HAMILTON: That's probably because the brain is releasing dopamine, which brings pleasure and reinforces our desire to do the same thing again. But of course when the stakes get higher, multitasking can stress you out.
Dr. MEYER: The brain areas that you would see light up and the neurotransmitters that would be getting released would be quite different if I was an air traffic controller trying to land a whole bunch of planes at La Guardia Airport. I wouldn't be having pleasure in that.
HAMILTON: For teenagers like Zach Weinberg and Alex Donesky, the experience of multitasking falls somewhere between the rush of skydiving and the anxiety of landing planes. Regardless, Alex says, it's all they know.
Mr. WEINBERG: Even for me right now, and I haven't been exposed to it that long, it's already natural to multitask, like, in these ways. When it becomes, like, your will is - your heart is in that place where you're just conditioned to it, that's how you're going to keep going.
HAMILTON: Even, he says, when you don't want to. Jon Hamilton, NPR News.
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