The Value of Mind Wandering in Solving Difficult Problems
Some problems can be solved best by taking a break from trying to solve them.
By Peter Gray Ph.D. Freedom to Learn
I begin this essay by listing five quite striking, possibly counterintuitive findings from research on problem solving.
1. People who show the symptoms of ADHD—notably, a tendency to be easily distracted from the task at hand—have been found repeatedly to be much better at solving certain kinds of problems than are people who don’t show these symptoms. I summarized and referenced some of the evidence for this in a previous essay (also see Boot, Nevicka, & Baas (2017).
2. People who, because of strokes or tumors, have suffered damage to the prefrontal lobes of the cortex (brain areas that help focus attention and help develop conscious problem-solving strategies) have been found to be much better than people with intact brains at solving certain kinds of problems (Reverberi et al., 2005).
3. Brain-intact people have been found to show great improvement at solving certain kinds of problems if a portion of their prefrontal lobes has been temporarily rendered less active by a process called transcranial direct current stimulation (which involves a slight electric current sent across the skull over the brain area to be made less active). (Luft et al, 2017.)
4. Dozens of experiments have shown that people who are stumped in solving certain kinds problem are subsequently much more likely to solve the problem if they take a break, in which they think about something else for awhile, than they are if they work continuously on the problem (for reviews, see Sio et al, 2017; Sio & Ormerod, 2009). This is called the “incubation effect.” A number of studies have shown that the incubation effect works best when, during incubation, the person is just daydreaming or working on some relatively easy set of tasks rather than focusing heavily on a new problem.
What are these “certain kinds of problems?” They are problems that cannot be solved through one’s routine, ingrained, well-trained ways of thinking. They are sometimes called “insight problems,” because when you finally do solve them the solution seems to jump out from nowhere, and you experience the classic “aha” phenomenon. Suddenly you see what you didn’t see before. It seems magical. From where did that solution come?
The solution must have come somehow from the unconscious mind. Our brain is an amazing machine, which is always working on many things at once. Our conscious experience of thought, which generally runs along a single track rather than many at once, reflects only a small portion of what the brain is doing. On this, if on nothing else, Freud was right: The conscious mind is just the tip of the iceberg. Apparently, when we stop consciously thinking about the problem that we have been unable to solve, the unconscious mind takes the problem on and continues to work on it in some way—not through the logical means of the conscious mind, but through some other kind of logic. There are various theories about what the unconscious mind is doing. One prominent theory is that it is checking out a broad range of potential links between elements of the problem and other information stored in memory, including links that are too remote for the conscious, logical mind to consider. Suddenly, the mind hits a link that works, that solves the problem, and this awakens the conscious mind—“Aha, I see it now!”
On the basis of this theory, the person with ADHD, or with a lesion in the prefrontal lobe, or with a temporarily suppressed prefrontal lobe, is more likely to solve such problems than are other people because they are less able to maintain fixed attention. They are more likely to allow their mind to wander and therefore more likely to allow these unconscious mechanisms to take over.
All the research I’ve referenced so far was done in the laboratory, with insight problems created specifically for research purposes. What about real-world problem solving? In a very recently published study, Shelly Gable, Elizabeth Hopper, and Jonathan Schooler, of the University of California, Santa Barbara. (2019), recruited 72 theoretical physicists and 113 professional writers (mostly screen writers) as participants in a study of problem solving related to their professions. Over a two-week period each participant was emailed a questionnaire, which asked them to describe the most creative idea, if any, they had that day related to their work. If they listed an idea, they were asked questions about what they were doing and thinking when they had the idea, and whether it entailed overcoming an impasse or felt like an “aha” moment, and how important and creative the idea was.
Of most interest for our purposes, the researchers found that approximately 20% of the creative ideas, for both physicists and writers, occurred at times when they were not thinking about the problem to which the idea pertained. It occurred while they were away from their work and thinking about something else. Moreover, these ideas were especially likely to be experienced as “aha” moments and to contain solutions to problems for which they had previously been at an impasse, that is, at a point where the problem had begun to seem unsolvable. So, the unconscious mind solves problems not just in the laboratory, but in people’s real professional lives as well.