Amazing of human memory

Half a year ago, in order to encourage my daughter to learn ancient Chinese prose, I specifically selected seven articles, including (The Story of Yueyang Tower),(Records of Zuiweng Pavilion), (Ode to Apang Palace),(Ode to Red Cliff), (Preface to Tengwang Pavilion), (Preface to Lanting Pavilion), (Ode to Returning Home) Reciting these articles in person and giving demonstration lectures, but you know how difficult it is for an adult to recite and remember these articles after years of not reading them, but after that period of time. A few months later, when I suddenly find that the difficult recitation before was so simple now, all the beautiful sentences were displayed in my mind, and could be expressed clearly and naturally. It was amazing. Although I hadn’t recited and read continuously for several months, they were so strong and clear that they appeared in my mind, even better than when I first recited them. What is the reason for this?😂