The puzzles look easy, and mostly they are. Given three words — “trip,” “house” and “goal,” for example — find a fourth that will complete a compound word with each. A minute or so of mental trolling (housekeeper, goalkeeper, trip?) is all it usually takes.
But who wants to troll?
Let lightning strike. Let the clues suddenly coalesce in the brain — “field!” — as they do so often for young children solving a riddle. As they must have done, for that matter, in the minds of those early humans who outfoxed nature well before the advent of deduction, abstraction or SAT prep courses. Puzzle-solving is such an ancient, universal practice, scholars say, precisely because it depends on creative insight, on the primitive spark that ignited the first campfires.
And now, modern neuroscientists are beginning to tap its source.
In a just completed study, researchers at Northwestern University found that people were more likely to solve word puzzles with sudden insight when they were amused, having just seen a short comedy routine.
“What we think is happening,” said Mark Beeman, a neuroscientist who conducted the study with Karuna Subramaniam, a graduate student, “is that the humor, this positive mood, is lowering the brain’s threshold for detecting weaker or more remote connections” to solve puzzles.
This and other recent research suggest that the appeal of puzzles goes far deeper than the dopamine-reward rush of finding a solution. The very idea of doing a crossword or a Sudoku typically shifts the brain into an open, playful state that is itself a pleasing escape, captivating to people as different as former US president Bill Clinton, a puzzle addict, and the famous amnesiac Henry Molaison, or HM, whose damaged brain craved crosswords.
And that escape is all the more tantalizing for being incomplete. Unlike the cryptic social and professional mazes of real life, puzzles are reassuringly soluble; but like any serious problem, they require more than mere intellect to crack.
“It’s imagination, it’s inference, it’s guessing; and much of it is happening subconsciously,” said Marcel Danesi, a professor of anthropology at the University of Toronto and the author of The Puzzle Instinct: The Meaning of Puzzles in Human Life.
“It’s all about you, using your own mind, without any method or schema, to restore order from chaos,” Danesi said. “And once you have, you can sit back and say, ‘Hey, the rest of my life may be a disaster, but at least I have a solution.’”
For almost a century scientists have used puzzles to study what they call insight thinking, the leaps of understanding that seem to come out of the blue, without the incremental drudgery of analysis.
In one classic experiment, the German psychologist Karl Duncker presented people with a candle, a box of thumbtacks and the assignment of attaching the candle to a wall. About a quarter of the subjects in some studies thought to tack the box to the wall as a support — some immediately, and others after a few failed efforts to tack wax to drywall.
The creative leap may well be informed by subconscious cues. In another well-known experiment, psychologists challenged people to tie together two cords; the cords hung from the ceiling of a large room, too far apart to be grabbed at the same time.
A small percentage of people solved it without any help, by tying something like a pair of pliers to one cord and swinging it like a pendulum so that it could be caught while they held the other cord. In some experiments researchers gave hints to those who were stumped — for instance, by bumping into one of the strings so that it swung. Many of those who then solved the problem said they had no recollection of the hint, though it very likely registered subconsciously.