In Praise of Idleness
Most of us have been led to believe that the off-task brain is a little like an idling engine — puttering along at rest until given a specific task to accomplish or a problem to focus on. But research involving the use of PET and MRI imaging technologies suggests that, in fact, our brains maintain an almost constant level of activity, even when we appear to be doing nothing.
According to Marcus Raichle, MD, a neurologist at Washington University School of Medicine in St. Louis, a number of interconnecting brain regions kick into a sort of neurological and metabolic hyperdrive whenever given a break from tasks that require more-directed, highly focused attention. You can see it on a PET scan: The same areas of the brain that light up when subjects allow their minds to wander from a problem or focused task promptly dim whenever they are asked to actively concentrate on something. And when those mind-wandering areas are active, they gobble glucose at an astonishing rate.
Based on the fact that the brain diverts attention from its demanding “downtime” activities only when called upon to divert blood, oxygen and glucose for more urgent purposes, Raichle and other brain researchers are concluding that whatever the brain is doing while apparently doing nothing may actually be profoundly important.
In a 2001 paper published in the Proceedings of the National Academy of Sciences, Raichle and his colleague Gordon Shulman, PhD, identified the cluster of regions in which this activity occurred, including the medial prefrontal cortex, hippocampus and posterior cingulate, which represent an arch through the midline of the brain. They dubbed these areas the “default network” and have continued to focus research efforts on precisely how the network operates — and for what purpose — ever since.
What’s clear so far is that the default network utilizes strong connections with the parts of our brains that process executive (decision-making) functions, memories, and content we deem to be of emotional significance or significant to our self-interest. And when active, parts of the network devour 30 percent more caloric energy (in the form of glucose) than nearly any other parts of the brain, suggesting that when it’s working, it’s working very hard indeed.
Precisely what it’s working on is the subject of ongoing research. Raichle and many of his fellow researchers hypothesize that the default network is responsible for processing the memories, observations and other random unsorted bits of material we’ve got floating around in our knowledge banks at any given time, potentially for the purposes of linking them or assessing their potential significance to our present and future circumstances
It may be that the default network is burning though glucose, in part, to create the amino acids and neurotransmitters it requires to build and maintain new synaptic circuits.
The act of daydreaming, in particular, seems to send the default network into action, and researchers now suspect this much-maligned activity may be one of the prime tools the brain employs in sorting and making sense of the chaotic bits and bytes we take in daily. In other words, giving your conscious mind a break now and then — not keeping it constantly focused on important matters — may be among the best ways to invite insights, ideas and solutions.
The Eureka Factor
You’ve probably heard plenty of people acknowledge that they get their best ideas in the shower. And you’ve no doubt heard the rumored story of Archimedes, who shouted his now-legendary “Eureka!” when he stepped into the bath, saw his bathwater rise and suddenly understood that the volume of water displaced must be equal to the volume of the part of his body he’d submerged, abruptly intuiting the answer to what had previously been an intractable mathematical problem.
There’s a reason so much genius has occurred in bathrooms, according to cognitive neuroscientist Mark Jung-Beeman, PhD, and it’s the same reason we often get great ideas while puttering in the garden, getting a facial, taking a walk or just waking up from a nap: Because these are precisely the types of circumstances in which we’re not trying to come up with genius ideas, or really any ideas at all. The body is relatively relaxed; the brain is being allowed to do whatever it likes, its circuits freed up for whatever associations and information-shuttling activities it deems worthwhile. And it’s those random associations that seem key both to large-scale breakthroughs and handy “aha!” moments.
Jung-Beeman, a researcher at Northwestern University in Evanston, Ill., has made a career of mapping the brain circuits involved in moments of spontaneous insight. And he has found that while the brain lays much of the groundwork for insight by expending focused attention on a particular problem, certain parts of the brain must actually relax and be allowed to wander a bit for the necessary connections and associations (most of which are churned up by the more loosely organized right hemisphere) to be made.
In studies of subjects attempting to solve complex puzzles, psychologist Joy Bhattacharya, PhD, a researcher at Goldsmiths, University of London, has been able to use electroencephalography (EEG) to successfully predict moments of insight up to eight seconds before the insights occur. He’s found that one key predictive indicator of an upcoming “aha!” is the presence of alpha waves (a brain-wave pattern associated with relaxation) emanating from the right hemisphere of the brain. Such activity makes the mind more receptive to new and unusual ideas, Bhattacharya suggests.
This explains, perhaps, why big-idea guys like Albert Einstein and mathematician Henri Poincaré have credited their best insights to the unconscious work their minds did while they were taking a break from what they ostensibly did best.
The upshot? Beyond a certain point, sitting for hours at your desk and working harder and longer to solve that problem or come up with that big idea may actually work against you. And that “certain point” may be mere minutes from now.