You may be surprised to learn that there is really no such thing as mentally multitasking. The human brain can only hold one conscious thought at a time.
Common use of the word “multi-task” actually has two distinct meanings: The first is physically doing two things at the same time, hopefully neither of which requires too much attention. For example, you may sometimes drive and talk on the phone simultaneously. This may not cause too much problem if the conversation is relatively light, you’re on familiar roads, and the traffic isn’t heavy.
However, if the road conditions get difficult, or the conversation gets intense, many people find themselves abandoning one task in order to focus their attention on the other (ever find yourself turning down the radio, or telling your caller you have to hang up, when you’re lost, or when the traffic suddenly gets heavy? Also note: using a cell phone while driving, whether it’s hand-held or hands-free, delays a driver’s reactions as much as having a blood alcohol concentration at the legal limit of .08 percent!)
More commonly, we use “multi-task” to describe the behavior of switching our attention rapidly back and forth between two tasks. Our thoughts can change so fast that it seems like we’re thinking about things simultaneously, but the process is actually called “cognitive switching.”
Studies have shown that either physically multi-tasking, or cognitive switching (mental “multi-tasking”) both increases the amount of time it takes to do a task, and also decreases the quality with which that task is done.
A study published by the American Psychological Association concluded that the ability to switch between tasks, which they term, “mental flexibility” generally peaks in the 20s and then decreases with age. The extent to which it decreases depends upon the type of tasks being performed. However, the findings of this study indicate that mental flexibility decreases an average of 30.9% from a person in their 40s to a person in their 70s.
For example, this could explain John McCain’s admitted “computer illiteracy” during the 2008 elections. Fluent use of a computer requires the ability to rapidly switch focus between the task the computer is needed for (sending an email, for example) and the task of operating the computer. Those who are not well-versed in computer use would find it difficult to do both of these things together.
Given all this, you may think that my advice to you would be to “never multitask.” Actually, I’m a big fan of multitasking. The key is the same as my primary belief: control your attention, control your life. As long as I have chosen when to multitask, instead of doing it out of habit.
For example, I think it’s fine to combine tasks that don’t require too much mental energy, such as catching up with a girlfriend by phone while I empty the dishwasher or fold the laundry. Neither of these things requires much concentration and the consequences of distraction are minor (I might have to ask my friend to repeat something, or put the dishes in the wrong cabinet.)
If I am driving down the highway and I answer the phone, out of habit, simply because it rings, I did not decide. I inadvertently relinquished control over the situation.
Do you skim your email while you’re on the phone, simply because it’s in front of you? Do you leave your email client open, with messages automatically downloading, all day, even while you’re trying to do other things? These are examples of sabotaging your own attention, rather than supporting it. You’ve created a situation where multitasking is the likely result, despite the fact that you intended to focus. You did not decide. You relinquished control.
If studies prove that multitasking causes you to take longer and perform worse, yet you find yourself routinely multitasking, this probably means that what you are putting out into the world is really only a fraction of your true talents, skills, and abilities. Now it’s up to you to decide if that’s ok with you or not.
I think multitasking has its time and place: the time and place you choose to engage in it. Other times, I suggest you choose to indulge your focus. You never know what kind of amazing things might happen!