Alzheimer's is a form of dementia that causes memory loss and confusion. In the early stages, which last 2-4 years, patients lose interest in activities and show short-term memory loss, though past memories remain. Towards the end of this stage, patients cannot perform jobs or schedules. The second stage lasts several years and is characterized by extreme confusion and memory failure, where patients recognize faces but avoid unfamiliar people to reduce confusion. Restlessness becomes frequent, especially in afternoons.