What do small children remember? And why do memories stick into adulthood?

Last August, I moved across the country with a child who was a few months shy of his third birthday. I assumed he’d forget his old life—his old friends, his old routine—within a couple of months. Instead, over a half-year later, he remembers it in unnerving detail: the Laundromat below our apartment, the friends he ran around naked with, my wife’s co-workers. I just got done with a stint pretending to be his long-abandoned friend Iris—at his direction.

We assume children don’t remember much, because we don’t remember much about being children. As far as I can tell, I didn’t exist before the age of 5 or so—which is how old I am in my earliest memory, wandering around the Madison, Wis. farmers market in search of cream puffs. But developmental research now tells us that Isaiah’s memory isn’t extraordinary. It’s ordinary. Children remember.

Up until the 1980s, almost no one would have believed that Isaiah still remembers Iris. It was thought that babies and young toddlers lived in a perpetual present: All that existed was the world in front of them at that moment. When Jean Piaget conducted his famous experiments on object permanence—in which once an object was covered up, the baby seemed to forget about it—Piaget concluded that the baby had been unable to store the memory of the object: out of sight, out of mind.

The paradigm of the perpetual present has now itself been forgotten. Even infants are aware of the past, as many remarkable experiments have shown. Babies can’t speak but they can imitate, and if shown a series of actions with props, even 6-month-old infants will repeat a three-step sequence a day later. Nine-month-old infants will repeat it a month later.

The conventional wisdom for older children has been overturned, too. Once, children Isaiah’s age were believed to have memories of the past but nearly no way to organize those memories. According to Patricia Bauer, a professor of psychology at Emory who studies early memory, the general consensus was that a 3-year-old child’s memory was a jumble of disorganized information, like your email inbox without any sorting function: “You can’t sort them by name, you can’t sort them by date, it’s just all your email messages.”

By those standards, Isaiah is a wizard of memory—the Joshua Foer of the preschool set. But it turns out that all children are Joshua Foer: Even very young children have bewilderingly good memories. Twenty years ago, a study on memories of Walt Disney World—the ne plus ultra memorable experience—surprised everyone involved: Children who’d been at Disney when they were only 3 years old could recount detailed memories of it 18 months later. Evidence has piled up ever since. A just-published paper on long-term recall found that a 27-month-old child who’d seen a “magic shrinking machine” remembered the experience some six years later.

Far from having no memories at all, very young children remember a lot like adults. In early infancy, the neural structures crucial for memory are coming online: the hippocampus, which is, very roughly, in charge of storing new memories; and the prefrontal cortex, which is, very roughly, in charge of retrieving those memories.

But these neural regions and their connecting pathways are still developing. And they capture only part of the present as it flows by.

Think of memory as like orzo, Bauer says. “It’s not like one big piece of lasagna noodle. Memories are made up of these little tiny bits of information that are coming in literally across the entire cortex. Parts of the brain are taking those little bits of information and knitting them together into something that’s going to endure and be a memory.” Adults have a fine-mesh net to catch the orzo. Babies have a big-holed colander: The orzo slips through. “What’s happening with the baby is that a lot of the information is escaping even as the baby is trying to get it organized and stabilized.” In early infancy, a lot of experiences never become memories—they slip away before they can be preserved.

Babies remember far more than anyone thought, in other words, but far less than any adult. It’s only around 24 months that children seem to get better colanders: They get better at catching the orzo—at organizing and processing information in a way that makes a memory out of an experience.