Alzheimer's disease affects 100 000 people in Sweden. There is no cure and the need is great. The disease is caused by the accumulation of the protein tau in neurons in the brain, which causes the cells to die. In addition, the cell's cleaning machinery - autophagy - is disrupted. Our hypothesis is that it is precisely the defective autophagy that causes the accumulation of tau. This project is about finding out if this is true by removing the autophagy function in mice with tau pathology and seeing if the pathology gets worse. As a therapy, we will try to see if increasing autophagy in brain cells has a positive effect and improves tau pathology. This has never been investigated in vivo before and we hope to contribute to the understanding of Alzheimer's.