Heading Home

Later that night, back at the Recapture Lodge, Mr. Kramer reclaims his laptop from the front desk. At first, he says he’ll wait to log on until he showers and rests. Then he decides to have a quick peek. He has received 216 e-mail messages, but nothing about the military grant.

“The $25 million saga continues,” he says, and logs off.

The next morning, he and Mr. Braver sit in the back of the car, heading to the airport, the pair of skeptics sharing beef jerky and a perspective. The trip didn’t transform them, but it did get them to change the way they think about their research  and themselves.

Mr. Braver says that when he retrieved his phone the night before, it dawned on him how much he turns to it in tiny moments of boredom: “Sometimes I do use it as an excuse to be antisocial.”

When he gets back to St. Louis, he says, he plans to focus more on understanding what happens to the brain as it rests. He wants to use imaging technology to see whether the effect of nature on the brain can be measured and whether there are other ways to reproduce it, say, through meditation.

Mr. Kramer says he wants to look at whether the benefits to the brain  the clearer thoughts, for example  come from the experience of being in nature, the exertion of hiking and rafting, or a combination.

Mr. Atchley says he can see new ways to understand why teenagers decide to text even in dangerous situations, like driving. Perhaps the addictiveness of digital stimulation leads to poor decision-making. Mr. Yantis says a late-night conversation beneath stars and circling bats gave him new ways to think about his research into how and why people are distracted by irrelevant streams of information.

Even without knowing exactly how the trip affected their brains, the scientists are prepared to recommend a little downtime as a path to uncluttered thinking. As Mr. Kramer puts it: “How many years did we prescribe aspirin without knowing the exact mechanism?”