The use of stem cells is a very interesting tool for the in vitro study of molecular mechanisms involved in neurodegenerative diseases since, from them, new cells could be generated that would be used to try to restore those that do not function correctly as a consequence of the pathology. The ultimate goal of much of the brain research is to discover treatments to stop or reverse neurodegenerative diseases, as well as the discovery of early markers of the disease that allow acting on them before their symptoms develop.