Alzheimer’s Day 2021: A hallmark of Alzheimer’s disease is gradual deterioration of memory. Here’s all you need to know about the disease on World Alzheimer’s Day 2021 Alzheimer’s disease is the most common form of dementia, which is an umbrella term used to describe general loss of memory, thinking skills and other day-to-day functions (such as cooking, paying bills, cleaning and even dressing). A hallmark of Alzheimer’s disease is gradual deterioration of memory. But it is a biological disease, which means that, besides seeing outwards symptoms such as memory loss, we can also measure the breakdown that occurs in the brain as a consequence of disease progression. Alzheimer’ s is identified by the presence of two proteins in the brain, known as amyloid and tau. Amyloid proteins aggregate into sticky clumps called “plaques”. And tau proteins tend to form “tangles”. While it is still unclear how amyloid and tau interact to cause the disease, these plaques and tangles seem to play ...