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We've all done it. Making breakfast while checking email. Paying bills while having a serious conversation with your significant other. And the most infamous one: driving while talking on a cell phone. It saves time, right? Getting two things done at once is better than just getting one thing done. Or is it?
Research shows that multitasking takes a toll on your mental energy, especially if the tasks are difficult ones. Apparently, the human brain is not designed to be able to do two or more things at once. A study showed that people are much slower when switching between tasks than they are when repeating the same task. Even when given more time between tasks, people were not as efficient when task-switching as when task-repeating. The brain can adjust to a new task, but the old task is still competing for mental energy with the new task. For example, driving while talking on a cell phone can get difficult when someone cuts you off in traffic. If you were mostly focused on your phone conversation, you would have to switch tasks to slam on the brakes. Switching back to the conversation after regaining your driving composure can be difficult - "What was he talking about??"
Multitasking involves two distinct stages: one is goal shifting and the other is rule activation. Goal shifting consists of deciding to focus on another task than the one you are currently focused on. Rule activation consists of turning off the "rules" for one task and turning on the "rules" for another. Going back to our driving example, not only would you have to consciously decide to return to the conversation after the traffic incident, but you would also have to think, "Ok, now that I can return to the gas pedal, I need to concentrate on what my friend was saying and answer him back." Navigating these two stages within your brain can actually take up as much as 40% of your productive time.
So what does all this mean in terms of daily life? Understanding that multitasking can put a serious strain on your mental energy can make a difference in your life. Instead of trying to cram everything into 5 minutes, take your time and do only one thing at a time. It may actually save you time and energy!
