We are interested in determining how brain plasticity contributes to behavior during development and in adulthood. We explore several mechanisms of structural plasticity, including neurogenesis, synaptogenesis, glial reactivity, and the extracellular matrix, to determine their contributions to neuronal oscillations and behavioral functions of the hippocampus, including social and non-social memory, and avoidance behavior. We use experience, genetic modifications, and hormone manipulations to probe plasticity mechanisms in the service of understanding behavioral change.