The Importance of Mind-Wandering

When people are immersed in monotony, they automatically lapse into a very special form of brain activity: mind-wandering. In a culture obsessed with efficiency, mind-wandering is often derided as a lazy habit, the kind of thinking we rely on when we don't really want to think. In recent years, however, neuroscience has dramatically revised our views of mind-wandering.

It’s easy to underestimate boredom. The mental condition, after all, is defined by its lack of stimulation; it’s the mind at its most apathetic. This is why the poet Joseph Brodsky described boredom as a “psychological Sahara,” a cognitive desert “that starts right in your bedroom and spurns the horizon.” The hands of the clock seem to stop; the stream of consciousness slows to a drip. We want to be anywhere but here.

However, as Brodsky also noted, boredom and its synonyms can also become a crucial tool of creativity. "Boredom is your window," the poet declared. "Once this window opens, don't try to shut it; on the contrary, throw it wide open."

Brodsky was right. The secret isn’t boredom per se: It’s how boredom makes us think. When people are immersed in monotony, they automatically lapse into a very special form of brain activity: mind-wandering. In a culture obsessed with efficiency, mind-wandering is often derided as a lazy habit, the kind of thinking we rely on when we don't really want to think. (Freud regarded mind-wandering as an example of “infantile” thinking.) It's a sign of procrastination, not productivity.

In recent years, however, neuroscience has dramatically revised our views of mind-wandering. For one thing, it turns out that the mind wanders a ridiculous amount. Last year, the Harvard psychologists Daniel Gilbert and Matthew A. Killingsworth published a fascinating paper in Science documenting our penchant for disappearing down the rabbit hole of our own mind. The scientists developed an iPhone app that contacted 2,250 volunteers at random intervals, asking them about their current activity and levels of happiness. It turns out that people were engaged in mind-wandering 46.9 percent of the time. In fact, the only activity in which their minds were not constantly wandering was love making. They were able to focus for that.

What's happening inside the brain when the mind wanders? A lot. In 2009, a team led by Kalina Christoff of UBC and Jonathan Schooler of UCSB used "experience sampling" inside an fMRI machine to capture the brain in the midst of a daydream. (This condition is easy to induce: After subjects were given an extremely tedious task, they started to mind-wander within seconds.) Although it's been known for nearly a decade that mind wandering is a metabolically intense process -- your cortex consumes lots of energy when thinking to itself -- this study further helped to clarify the sequence of mental events:

Activation in medial prefrontal default network regions was observed both in association with subjective self-reports of mind wandering and an independent behavioral measure (performance errors on the concurrent task). In addition to default network activation, mind wandering was associated with executive network recruitment, a finding predicted by behavioral theories of off-task thought and its relation to executive resources. Finally, neural recruitment in both default and executive network regions was strongest when subjects were unaware of their own mind wandering, suggesting that mind wandering is most pronounced when it lacks meta-awareness. The observed parallel recruitment of executive and default network regions—two brain systems that so far have been assumed to work in opposition—suggests that mind wandering may evoke a unique mental state that may allow otherwise opposing networks to work in cooperation.

Two things worth noting here. The first is the reference to the default network. The name is literal: We daydream so easily and effortlessly that it appears to be our default mode of thought. The second is the simultaneous activation in executive and default regions, suggesting that mind wandering isn't quite as mindless as we'd long imagined. (That's why it seems to require so much executive activity.) Instead, a daydream seems to exist in the liminal space between sleep dreaming and focused attentiveness, in which we are still awake but not really present.

Last week, a team of Austrian scientists expanded on this result in PLoS ONE. By examining 17 patients with unresponsive wakefulness syndrome (UWS), 8 patients in a minimally conscious state (MCS), and 25 healthy controls, the researchers were able to detect the brain differences along this gradient of consciousness. The key difference was an inability among the most unresponsive patients to "deactivate" their default network. This suggests that these poor subjects were trapped within a daydreaming loop, unable to exercise their executive regions to pay attention to the world outside. (Problems with the deactivation of the default network have also been observed in patients with Alzheimer's and schizophrenia.) The end result is that their mind's eye is always focused inwards.

The last bit of mind wandering research worth highlighting also comes from the Schooler lab. He's demonstrated that people who consistently engage in more mind-wandering -- Schooler gives subjects a slow section of War and Peace, and then times how long it takes before they start thinking about something else -- also score significantly higher on various measures of creativity. However, not all daydreams are equally effective at inspiring new ideas. In his experiments, Schooler distinguishes between two types of daydreaming. The first type occurs when people notice they are daydreaming only when prodded by the researcher. Although they’ve been told to press a button as soon as they realize their mind has started to wander, these people fail to press the button. The second type of daydreaming occurs when people catch themselves during the experiment – they notice they’re mind-wandering on their own. According to Schooler’s data, individuals who are unaware of their mind-wandering don't exhibit increased creativity.

The point is that it's not enough to simply daydream. Letting the mind drift off is the easy part. What's much more difficult (and more important) is maintaining a touch of meta-awareness, so that if you happen to come up with a useful new idea while in the shower or sitting in traffic you're able to take note; the breakthrough isn't squandered.

Taken together, these studies suggest that mind wandering is ubiquitous -- we spend nearly half our waking life in a daydream -- but it's also a talent we need to develop. (The worst case scenario, of course, is that a serious brain injury leaves us unable to escape from the daydreaming rabbit hole.) Instead of completely zoning out, we should work on staying a little more self-aware, ensuring there's still some activity in the executive areas of the brain. Ennui is a cognitive gift, but it must be properly unlocked. We can get better at being bored.

Image: Chandrahadi Junato/Flickr