TECHNOLOGY has given us many gifts, among them dozens of new ways to grab our attention. It’s hard to talk to a friend without your phone buzzing at least once. Odds are high you will check your Twitter feed or Facebook wall while reading this article. Just try to type a memo at work without having an e-mail pop up that ruins your train of thought.

But what constitutes distraction? Does the mere possibility that a phone call or e-mail will soon arrive drain your brain power? And does distraction matter — do interruptions make us dumber? Quite a bit, according to new research by Carnegie Mellon University’s Human-Computer Interaction Lab.

There’s a lot of debate among brain researchers about the impact of gadgets on our brains. Most discussion has focused on the deleterious effect of multitasking. Early results show what most of us know implicitly: if you do two things at once, both efforts suffer.

In fact, multitasking is a misnomer. In most situations, the person juggling e-mail, text messaging, Facebook and a meeting is really doing something called “rapid toggling between tasks,” and is engaged in constant context switching.