University of California, San Francisco neuroscientist Adam Gazzaley
and California State University, Dominguez Hills professor emeritus Larry Rosen explain in their book "The Distracted Mind: Ancient Brains in a High Tech World" why people have trouble multitasking, and specifically why one's productivity output is lowered when keeping up with emails
, for example. Lesley McClurg writes via KQED Science: When you engage in one task at a time, the prefrontal cortex works in harmony with other parts of the brain, but when you toss in another task it forces the left and right sides of the brain to work independently. The process of splitting our attention usually leads to mistakes. In other words, each time our eyes glance away from our computer monitor to sneak a peak at a text message, the brain takes in new information, which reduces our primary focus. We think the mind can juggle two or three activities successfully at once, but Gazzaley says we woefully overestimate our ability to multitask.
In regard to answering emails, McClurg writes: Gazzaley stresses that our tendency to respond immediately to emails and texts hinders high-level thinking. If you're working on a project and you stop to answer an email, the research shows, it will take you nearly a half-hour to get back on task. "When a focused stream of thought is interrupted it needs to be reset," explains Gazzaley. "You can't just press a button and switch back to it. You have to re-engage those thought processes, and recreate all the elements of what you were engaged in. That takes time, and frequently one interruption leads to another." In other words, repetitively switching tasks lowers performance and productivity because your brain can only fully and efficiently focus on one thing at a time. Plus, mounting evidence shows that multitasking could impair the brain's cognitive abilities. Stanford researchers studied the minds of people who regularly engage in several digital communication streams at once. They found that high-tech jugglers struggle to pay attention, recall information, or complete one task at a time. And the habit of multitasking could lower your score on an IQ test, according to researchers at the University of London.
The saving grace is that we don't need to ditch technology as "there's a time and place for multitasking," according to Gazzaley. "If you're in the midst of a mundane task that just has to get done, it's probably not detrimental to have your phone nearby or a bunch of tabs open. The distractions may reduce boredom and help you stay engaged. But if you're finishing a business plan, or a high-level writing project, then it's a good idea to set yourself up to stay focused."