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Kids are often reprimanded for day-dreaming in school, so many of us grow up believing that day-dreaming, or mind-wandering, is something to be guarded against if we want to do well in life.
It’s a no-brainer—or is it?
No doubt about it: There are numerous situations when attending to what is being said, watching how something is done, or thinking about the words we are reading and what they mean is essential if we want to learn something new, or understand what someone is telling us, perhaps opening us up to their feelings and our ability to empathize.
Yet every one of us is also prey to zoning out. Some studies have suggested that for most of us, our minds wander off somewhere else for almost half of our waking hours. This suggests that mind-wandering must have some evolutionary significance, or some benefit.
Until quite recently, neuroscientists thought that the electrical activity in the brain in its resting state—observed by techniques such as EEG (electroencephalography)—for example, when we are sitting quietly with our eyes closed allowing our minds to wander aimlessly, was simply background neural noise. Neuroscientists refer to this slow voltage fluctuation, with a frequency of 8 to 13 cycles per second, as the “alpha wave." When the eyes are open and the brain focused, the alpha wave is suppressed by a faster “beta wave."
Various imaging techniques have also been used to see where in the brain the blood flow is greatest. This was assumed to point to locations in the brain that were currently most active, and correlated with an individual’s engagement on a specific task. However, studies over the past 15 years have shown that blood flow to the resting brain isn’t much lower than when it is focused and engaged in a specific task. Indeed, wider regions of the brain are active when the brain is “idling” than when it is focused on a task. These brain regions active when the brain is “resting” were dubbed the “default-mode network” in 2001 by neurologist Marcus Raichle from Washington University.
In his engaging 2014 book, The Wandering Mind: What the Brain Does When You’re Not Looking, Michael Corballis suggests thinking of the brain like a small town, where people mill about, getting on with their everyday lives. This is the “default-mode network” of the town. When a big event happens, such as a football game, many people flock to the field, becoming focused on a specific activity, while the rest of the town—the default-mode network—grows quiet.
Perhaps the trick with our minds, as with many other things in life, is balance: There is a time for focus and a time for mind-wandering. We can control, to some extent, when our minds wander, and there are many situations where this is advantageous. The most obvious of these is being creative; without time to daydream, many wonderful novels would never be written, nor artworks completed. We can daydream about a holiday we had last summer, and, just as easily, about a holiday we want to have next summer. Dreaming during sleep, and some types of hallucinations, are also forms of mind-wandering—generally not under our control and often hard to recall.
Of course, a lot of mind-wandering is negative and intrusive, and difficult to tame. Ruminating about things that have made us miserable and things we are worried about is something we could do without. The more serious the worry, the more likely it is to wander intrusively into our thoughts when we are desperately trying to focus on some other, more useful or pleasant activity. Some therapists suggest that worriers should put aside 15 minutes at the same time every day—perhaps early evening—specifically for worrying. They can spend this entire time actively worrying, and when it's over, they are free to stop, and move on to another activity. In a sense, this is forcing negative mind-wandering out of the default-mode network and onto the playing field for an intense workout. It doesn’t work for everyone, or for every problem that worries us, but it could be worth a try.
I have always sought out times when I can concentrate on mind-wandering, preferably lying on an isolated, sunny beach on a remote island, pretending to read, but in truth, making stuff up in a meandering sort of way. Walking along the beach, looking at the waves, and saying "hullo" to the rare birds that seem to know I’m no threat to them is an even stronger stimulus for my mind to go wandering off on tangents, some of which later (probably on another walk) might develop into a new idea or plot twist for a book. (If you think I am day-dreaming about this remote island, check out the photos on my author website. I enjoy mind-wandering so much that I have now made my home there…)
For those of you who harbor guilty feelings about your time-wasting/day-dreaming proclivities, take heart from a study discussed by Corballis in his book: Jonathan Schooler and his colleagues from the University of California at Santa Barbara asked students to read the opening chapters of War and Peace for 45 minutes and to press a key whenever they caught themselves zoning out. On average, students zoned out 5.4 times. Students were also interrupted six times at random intervals to see if they were on task, and lo and behold, on average each student was caught zoning out an extra 1.2 times. Much of the time we’re not even aware our minds are wandering.
But there is a joyful finding in the follow-up to this study: The students whose minds wandered most also scored best on a range of measures of creativity.
