A study from Albert Einstein College of Medicine, published in PLOS Biology, links late-adolescent brain remodeling in mice to temporary instability in contextual memory circuits. The work centers on the retrosplenial cortex and perineuronal nets, protective lattice-like structures that stabilize neural circuitry. Researchers report that perineuronal nets diminish during late adolescence before rebuilding in adulthood, coinciding with a period when memories formed earlier become temporarily harder to retrieve with less precision. They describe effects confined to the retrosplenial cortex rather than the hippocampus. The study proposes a biological mechanism for why access to established memories can change during development, aligning the mouse timeline with human data that indicates continued brain maturation into mid-to-late 20s. Senior author Jelena Radulovic, MD, PhD, and lead author Hui Zhang, PhD, describe the association between behavior and circuit stabilization changes as a key explanatory step for developmental memory dynamics.