Keck School of Medicine of USC Dec 3 2025 Researchers at the Mark and Mary Stevens Neuroimaging and Informatics Institute (Stevens INI) at the Keck School of Medicine of USC have identified a previously unknown pattern of organization in one of the brain's most important areas for learning and memory. The study, published in  Nature Communications, reveals that the CA1 region of a mouse's hippocampus, a structure vital for memory formation, spatial navigation, and emotions, has four distinct