Virtual-reality technology is being used to decode the inner workings of the human brain. By tasking people and rodents with solving puzzles inside virtual spaces, neuroscientists hope to learn how the brain navigates the environment and remembers spatial information. In this documentary, Shamini Bundell visits three neuroscience labs that are using virtual-reality technology to explore the brain. She uncovers the many benefits — and unsolved challenges — of performing experiments in virtual worlds.