Environmental enrichment—with infrastructure, unfamiliar odors and tastes, and toys and puzzles—is often used in zoos, laboratories, and farms to stimulate animals and increase their wellbeing. Stimulating environments are better for mental health and cognition because they boost the growth and function of neurons and their connections, the glia cells that support and feed neurons, and blood vessels within the brain. But what are the deeper molecular mechanisms that first set in motion these large changes in neurophysiology? That’s the subject of a recent study in Frontiers in Molecular Neuroscience.