Category:

this little exercise to see why:

* * *

Time yourself while you recite the first two lines of this nursery

rhyme:

How long did it take to say these eleven words? About four seconds?

Now time yourself while you count to eleven.

Four seconds again? So, it takes about eight seconds to recite the

two lines of verse and then count to eleven.

Now time yourself as you close your eyes and alternate between

saying the words of the nursery rhyme and the numbers. That is:

"Mary-one, had-two, a-three," and so on.

How long does this take? Around sixteen to twenty seconds?

* * *

The additional time it takes to alternate between the words of the nursery rhyme and the numbers one to eleven is the so-called switching cost. It takes more time because you have to keep in mind where you are in the alternating sequence of words and numbers while also fighting the tendency to complete the sequence you have just left. That is, if you say the word "little" you automatically want to say "lamb" next, rather than "four." Much of the switching cost

results from what's known as the "inhibition of return"—the mental focus needed to stop the mind from sliding backward into the previous task. Inhibiting one task and starting another—many times in succession, for hour after hour—consumes time and mental energy. Such multitasking might feel like you are doing many things at once in parallel, whereas in reality you are simply jumping from one task to another very inefficiently. And the more complex the task, the more inefficient the switching becomes. According to some studies, it can take around twenty minutes to refocus on a complex task after an interruption—and sometimes far longer. Repeated switching has a more insidious consequence, too. As each day progresses, and the weeks move into years, your mind can become shallower and shallower. Your attention span begins to erode. Your mind starts behaving like a skipping stone, bouncing off the surface of a pond. You may become better at switching, but less efficient at focusing on the tasks that you switch to. And because you can hold less and less in your mind, you need to switch more often, which means that you slow down

even more as all the different priorities compete for the diminishing space of your mind.

There's an emotional cost, too. Because you are focusing your finite mental energy on the difficult task of switching, rather than working, such interruptions make you feel irritable and short-tempered. It can feel like you actually need that little burst of angry energy to switch back to the task that was interrupted. And it's stressful. These changes can become hardwired into your brain, so that you end up being quicker to anger and slower to laugh.

Nor are these problems confined solely to work. Looking after family and keeping a home running smoothly were once considered major tasks in themselves. Now, often out of necessity, they have been squeezed to the margins. This, in turn, means that maintaining a social life is far more difficult and having some genuine free time can seem all but impossible. Even if you do manage to find a little time for yourself, it might be interrupted by the arrival of an email from your boss, an alert from your calendar, or perhaps a ping from a social media or auction site. Even something as simple as picking up the phone to check the time can mean being confronted with a long list of alerts, banners, and notifications. Each one grabs a moment of your life—then trying to ignore or suppress them snatches away the next.

None of these is a difficulty in itself, but they can all combine to become a major problem when you have too much to do and not enough time to do it all. In this way, they can add to feelings of being swamped and overwhelmed. And it's hardly surprising, then, that you can end up feeling increasingly frazzled and on the edge of burning out.

Although such a state is distressing and exhausting, something extra is needed to turn it into clinical-level anxiety, stress, or depression. It's called entanglement; it's when you become so trapped and enmeshed in difficulty that you cannot see a way out, no matter how hard you try. It's when you begin to overthink and to brood, becoming wrapped up in negativity. But it's not the "negative" feelings themselves that are the problem—they are symptoms; rather, it's the way that they become entangled with each other to deepen and prolong your suffering that is the root of your difficulties. Each one nestles in and supports the others. They can become so intertwined that one sad thought triggers the next, and the next, and the next, in a vicious downward spiral, dragging down with them your feelings, your body's energy levels, and your motivation to do the things that might support and nourish you.