There is a common belief that you can do multiple things at once and be more productive. The problem is that your brain can not focus on more than one thing at once, unless they are tasks that require very little thinking. For instance you can chew gum while you work, however your brain can not simultaneously focus on multiple complex tasks at the same time. Instead your brain must switch its attention from one thing to another, and every time you do this your brain undergoes a process that takes a fractions of a second or more.
According to the book Brain Rules by John Medina
Multitasking, when it comes to paying attention is a myth. The brain naturally focuses on sequentially, one at a time. This attentional ability is not capable of multitasking…To put it bluntly. Research shows that we can’t multitask. We are biologically incapable of processing attention rich inputs simultaneously.
Every time you switch tasks, your brain must undergo a specific process called rule activation. When your brain wants to start a new task, your anterior prefrontal cortex activates and sends out a two part message. The two parts include a search query to find the neurons responsible for doing the task, and a command to arouse the specific neurons once discovered. When you need to switch your attention to something else your brain must disengage from the current task, then activate the anterior prefrontal cortex, which sends out a new message to find the neurons you need for the next task and activate them. This process takes several tenths of a second.
“Studies show that a person who is interrupted takes 50% longer to accomplish a task. Not only that, he or she makes up to 50% more errors.”
-Brain Rules
Some evidence that shows how bad we are at multitasking is the awful driving performance of people who drive while talking on their cell phone.
According to Brain Rules “Cellphone talkers are a half second slower to hit the brakes in emergencies, slower to return to normal speed after an emergency, and more wild in their following distance behind the vehicle in front of them. In a half second a driver going 70 miles per hour travels 51 feet…50% of the visual cues spotted by attentive drivers are missed by cell phone talkers…they get in more wrecks than anyone except very drunk drivers.”
So if you are serious about getting more done, turn off the email alerts and close your email, close the internet browser windows you are not using, and limit unscheduled co-worker interruptions. You’ll be more productive and probably less stressed by not trying to do a million things at once.