This slide shows a neuritic plaque, one of the most important histological hallmarks of Alzheimer's disease. The plaque occurs in large numbers in the cerebral cortex. It usually contains a core of amyloid materials, which is called beta-amyloid protein, with a corona of irregular or dystrophic nerve endings, described as neurites.

The presence of a few neuritic plaques can be seen in normal ageing. The presence of a large number of neritic plaques is usually due to Alzheimer's disease.