Increased expression and function of cell cycle proteins in Alzheimer’s disease (AD) brain signifies exit of neurons from the G0 phase of the cell cycle. However we propose that neurons do not actively progress through various stages of the cell cycle and likely do not exit G1. Instead, we believe that multiple intracellular signaling pathways activated during AD induce cell cycle proteins to regulate cell death pathways and contribute to the formation of neurofibrillary tangles.