That's because the concept of multitasking has been researched by Stanford University recently. Their findings are creating quite a stir! People who multi-task a lot are awful at it, while those who do not multi-task can do it much better. Exactly opposite of what you'd think.
The shocking discovery of this research is that [high multitaskers] are lousy at everything that's necessary for multitasking. The irony here is that when you ask the low multitaskers, they all think they're much worse at multitasking and the high multitaskers think they're gifted at it.
The full research findings are here. Interesting food for thought. Perhaps this exists because the process of multi-tasking appears to be easier than it actually is, or perhaps the more you do it, the more your skills deteriorate.
Or perhaps, the study itself is flawed. Cathy Davidson takes it to task for poor research design, basically saying the test measures your ability to focus on one item when others are interfering. But multi-tasking is not solely a skill of blocking external stimuli, but rather keeping track of multiple stimuli.
Two thoughts. One is we need to examine this cognitive ability more closely in schools. We have all used the rhetoric that "digital natives can multi-task". We need full analysis of whether they can multi-task well, or if they just multi-task a lot. Similar to saying my son does cartwheels all the time, but that doesn't mean he's good at them. If we are going to design instruction with multiple tasks running concurrently, we better know as educators that it truly leads to better learning and not just trust the rhetoric.
Second thought, and I'm taking this from the most mind-stretching blog currently in my reader. Jack Uldrich at Unlearning 101 argues that while the results of the research are open for debate, one separate thought ist standing out. That being those who don't multi-task think they are lousy at it, and those who do multi-task think they are gifted at it. He labels this as over-confidence, one of the most important things we need to "unlearn" in order to be successful.
I like the way Uldrich articulates this:
If you are a multi-tasker, I am not suggesting that you unlearn the skill -- only how proficient you believe you are at the skill. (Preferably, I'm hoping you'll unlearn your over-confidence before you slam into the side of my car at some intersection because you were texting a friend while at the same time checking out the latest Tweet from Shaq.)
More on unlearning: Unlearning as a 21st Century Skill