GlossaryPlaque: Abnormal clusters of chemically “sticky” proteins called beta-amyloid that build up between nerve cells.Tangle: Aggregates of hyperphosphorylated tau protein that are most commonly known as a primary marker of Alzheimer's disease Dementia: A chronic disorder of the mental processes caused by brain disease or injury and marked by memory disorders, personality changes, and impaired reasoning. Published on Nov 18, 2014Last Updated on Nov 25, 2019