For about a month now, Wynn, 17, has been practicing at home using an unusual online program that prompts him to match graphs to equations, dozens upon dozens of them, and fast, often before he has time to work out the correct answer. An equation appears on the screen, and below it three graphs (or vice versa, a graph with three equations). He clicks on one and the screen flashes to tell him whether he’s right or wrong and jumps to the next problem. “I’m much better at it,” he said, in a phone interview from his school, New Roads in Santa Monica, Calif. “In the beginning it was difficult, having to work so quickly; but you sort of get used to it, and in the end it’s more intuitive. It becomes more effortless.”
For years school curriculums have emphasized top-down instruction, especially for topics like math and science. Learn the rules first — the theorems, the order of operations, Newton’s laws — then make a run at the problem list at the end of the chapter. Yet recent research has found that true experts have something at least as valuable as a mastery of the rules: gut instinct, an instantaneous grasp of the type of problem they’re up against. Like the ballplayer who can “read” pitches early, or the chess master who “sees” the best move, they’ve developed a great eye.
Now, a small group of cognitive scientists is arguing that schools and students could take far more advantage of this same bottom-up ability, called perceptual learning. The brain is a pattern-recognition machine, after all, and when focused properly, it can quickly deepen a person’s grasp of a principle, new studies suggest. Better yet, perceptual knowledge builds automatically: There’s no reason someone with a good eye for fashion or wordplay cannot develop an intuition for classifying rocks or mammals or algebraic equations, given a little interest or motivation.
“When facing problems in real-life situations, the first question is always, ‘What am I looking at? What kind of problem is this?’ ” said Philip J. Kellman, a psychologist at the University of California, Los Angeles. “Any theory of how we learn presupposes perceptual knowledge — that we know which facts are relevant, that we know what to look for.”
The challenge for education, Dr. Kellman added, “is what do we need to do to make this happen efficiently?”
Scientists have long known that the brain registers subtle patterns subconsciously, well before a person knows he or she is learning. In a landmark 1997 experiment, researchers at the University of Iowa found that people playing a simple gambling game with decks of cards reported “liking” some decks better than others long before they realized that those decks had cards that caused greater losses.. Some participants picked up the differences among decks after just 10 cards.
Experts develop such sensitive perceptual radar the old-fashioned way, of course, through years of study and practice. Yet there is growing evidence that a certain kind of training — visual, fast-paced, often focused on classifying problems rather then solving them — can build intuition quickly. In one recent experiment, for example, researchers found that people were better able to distinguish the painting styles of 12 unfamiliar artists after viewing mixed collections of works from all 12 than after viewing a dozen works from one artist, then moving on to the next painter. The participants’ brains began to pick up on differences before they could fully articulate them.
“Once the brain has a goal in mind, it tunes the perceptual system to search the environment” for relevant clues, said Steven Sloman, a cognitive scientist at Brown University. In time the eyes, ears and nose learn to isolate those signs and dismiss irrelevant information, in turn sharpening thinking.
Good teachers at all levels already have their own techniques to speed up this process — multiplication flash cards, tips to break down word problems, heuristic rhymes — but scientists are working to tune students’ eyes more systematically and to build understanding of very abstract concepts.
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