Some years ago, a British university issued a study of children’s geographical knowledge of the area around their homes. In the 1960s, when all kids had bikes and no instructions other than to be home at suppertime, children knew the contours of an area extending four or five miles in any given direction. In the 2000s, with fearful parents who ferried them around amid overmanaged schedules, that territory had shrunk to two or three blocks.

That’s a tragedy in the making, because new places mean new experiences mean new knowledge. New knowledge means a better workout for the hippocampus, the part of the brain that governs our memory and our ability to plan ahead. A bigger hippocampus means a more active mind. The converse, of course, is true as well, yielding a world of dullards.

“The number and complexity of navigational tasks a person practices influences the amount of gray matter,” writes Brooklyn-based journalist M.R. O’Connor in her new book Wayfinding: The Science and Mystery of How Humans Navigate the World. That’s a conclusion she happened on while researching her book, which was born, she tells Kirkus, by way of a chance meditation on technology. “I looked at my phone one day and I thought, Wow, I used to not have this thing and had to get around on my own. Now I have this piece of technology, and I use it all the time. I don’t have to think about getting places….I wonder what it’s doing to my brain.”

O’Connor’s last book, Resurrection Science (2015), on the de-extinction movement, which employs modern science to the project of bringing creatures like the long-gone mammoth and saber-tooth tiger back to life, had a subtheme: What happens when technology meets conservation? Just so, Wayfaring looks at what happens to the brain when we are called on to, say, navigate by the stars, in the way of the Polynesian seafarers who crossed the Pacific thousands of years ago, and what happens when we allow such knowledge to die with the technological convenience of GPS, Waze, and their kin. It’s a complicated story, especially when old knowledge, once dead, is similarly made de-extinct. “There are forgotten heroes out there who are educating young people in traditional ways,” says O’Connor, “and it’s making their lives better.”

For one thing, she notes, children’s development hinges on a knowledge of how to get around in the world: There’s a solid connection between navigational skills and what she calls “brain freedom”—the autonomy that comes with knowledge, skill, and self-confidence. “How do we give our children the freedom and autonomy to explore?” she asks. The answer, in short, is that too often we don’t, leading to that contraction of geographical mastery—and it cheats children in the long run.

 On that note, an intriguing notion that O’Connor examines links the mental decline that often accompanies aging to the decline in navigating from place to place as one’s world shrinks: the smaller the space in which we roam, the smaller our thoughts. Says O’Connor, “I hadn’t been fully aware until I got into this book of the connection between navigation and memory, and I hadn’t realized how deep the connection to the hippocampus was. It’s not just where we store memory, but it’s also where we envision the future.”

If we don’t know where we are, we don’t know what lies ahead, in other words. O’Connor draws on neuroscience, mathematics, geography, and other sciences and talks with scholars, explorers, pilots, teachers, children, and some of those forgotten heroes—Polynesian elders who are teaching young people how to sail from place to place, “an act of self-control and authority,” as she writes, “taking control over identity by wrenching it away from missionaries, colonial governments, tourism economies—even scientists and anthropologists.”

The lesson from M.R. O’Connor’s book, a model of scientific journalism, seems clear: Turn off the GPS and the phone, grab a map, head out the door, explore at leisure, stretch your brain and your spatial memory—and grow your freedom.

Gregory McNamee is a contributing editor.