MAPT and frontotemporal dementia: In order to model tau pathology in mice and explore behavioral changes induced by tau overexpression, we injected mouse neonates in the lateral ventricles (ICV injection, postnatal day 2) with AAV2/6-pgk vectors either encoding the WT form of human 4R0N tau (AAV-WT), or encoding the P301S mutant tau associated with frontotemporal dementia (AAV-P301S) (Fig. 1a).