PSEN1 and Cognitive impairment: A variety of AD mouse models have been generated, such as for example APP/PS1, B6C3-Tg, 5xFAD, 3xTg, APPSw-NSE (www.alzforum.org) [50,52,53,54,55] of which the APP/PS1 model is most widely used featuring amyloid plaque generation, mild to robust neuronal cell loss and cognitive impairments [51,56,57,58,59,60,61,62] and reporting on cognitive improvement after NSC transplantation [56,57,61,62].