After a lesson, an echo lingers in a child's head: faces, objects, places. For the first time, scientists have watched this echo in children aged 6 to 17. They showed the children scenes and then simply asked them to rest for five minutes.
The younger the child, the broader the region of this replay in the front of the brain. In a six-year-old, the echo spreads across the whole frontal area; in a seventeen-year-old, it gathers into a single spot. But memory works equally well in everyone.
The echo after a lesson is not just words. It is a mechanism that keeps developing throughout childhood. While a child stares at the ceiling, the brain replays what was learned, turning a random episode into a personal story.
Children who thought about the task during rest remembered better, but their neural replay did not differ from those who did not think about it. This means that the brain consolidates memories even without conscious effort.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.