Recently, researchers have found even more positive news. The brain, as it traverses middle age, gets better at recognizing the central idea, the big picture. If kept in good shape, the brain can continue to build pathways that help its owner recognize patterns and, as a consequence, see significance and even solutions much faster than a young person can.

Image A really old brain — from a 19th-century textbook. Credit... Illustration from iphotostock.com

The trick is finding ways to keep brain connections in good condition and to grow more of them.

“The brain is plastic and continues to change, not in getting bigger but allowing for greater complexity and deeper understanding,” says Kathleen Taylor, a professor at St. Mary’s College of California, who has studied ways to teach adults effectively. “As adults we may not always learn quite as fast, but we are set up for this next developmental step.”

Educators say that, for adults, one way to nudge neurons in the right direction is to challenge the very assumptions they have worked so hard to accumulate while young. With a brain already full of well-connected pathways, adult learners should “jiggle their synapses a bit” by confronting thoughts that are contrary to their own, says Dr. Taylor, who is 66.

Teaching new facts should not be the focus of adult education, she says. Instead, continued brain development and a richer form of learning may require that you “bump up against people and ideas” that are different. In a history class, that might mean reading multiple viewpoints, and then prying open brain networks by reflecting on how what was learned has changed your view of the world.

“There’s a place for information,” Dr. Taylor says. “We need to know stuff. But we need to move beyond that and challenge our perception of the world. If you always hang around with those you agree with and read things that agree with what you already know, you’re not going to wrestle with your established brain connections.”

Such stretching is exactly what scientists say best keeps a brain in tune: get out of the comfort zone to push and nourish your brain. Do anything from learning a foreign language to taking a different route to work.