These genetic variations affect the brain’s regulation of dopamine, the neurotransmitter associated with the processing of rewards and new stimuli (and drugs like cocaine). The variations have been linked to faster reaction times, attention deficit hyperactivity disorder and a higher penchant for novelty-seeking and risk-taking.

But genes, as usual, are only part of the story. Researchers have found that people’s tendency for novelty-seeking also depends on their upbringing, on the local culture and on their stage of life. By some estimates, the urge for novelty drops by half between the ages of 20 and 60.

Dr. Cloninger, a professor of psychiatry and genetics at Washington University in St. Louis, tracked people using a personality test he developed two decades ago, the Temperament and Character Inventory. By administering the test periodically and chronicling changes in people’s lives over more than a decade, he and colleagues looked for the crucial combination of traits in people who flourished over the years — the ones who reported the best health, most friends, fewest emotional problems and greatest satisfaction with life.

What was the secret to their happy temperament and character? A trio of traits. They scored high in novelty-seeking as well in persistence and “self-transcendence.” Persistence, the stick-to-it virtue promoted by strong-willed Victorians, may sound like the opposite of novelty-seeking, but the two traits can coexist and balance each other.

“People with persistence tend to be achievers because they’ll keep working at something even when there’s no immediate reward,” Dr. Cloninger says. “They’ll think, ‘I didn’t win this time, but next time I will.’ But what if conditions have changed? Then you’re better off trying something new. To succeed, you want to be able to regulate your impulses while also having the imagination to see what the future would be like if you tried something new.”

The other trait in the trio, self-transcendence, gives people a larger perspective. “It’s the capacity to get lost in the moment doing what you love to do, to feel a connection to nature and humanity and the universe,” Dr. Cloninger says. “It’s sometimes found in disorganized people who are immature and do a lot of wishful thinking and daydreaming, but when it’s combined with persistence and novelty-seeking, it leads to personal growth and enables you to balance your needs with those of the people around you.”