In the medical world, a prion is a proteinaceous infectious protein called cellular prion protein (PrPc). PrPc is naturally located on cells that are found within the central nervous system, but it can be found on the surface of other tissues as well. Somehow, the folding of the protein becomes abnormal. The mis-folded proteins become templates for other proteins. The newly mis-folded proteins also become templates and cause other proteins to become mis-folded. This process continues until a plaque-like mass of the proteins is formed within the central nervous system that interferes with normal synapses. The brain cells eventually die. What appears to be a hole within the brain occurs where a mass of brain cells are lost. As the process continues, the brain may take on a spongy-like appearance. This can lead to brain disorders such as scrapie, encephalopathy, bovine spongiform (also known as “mad cow disease”), and Creutzfeldt-Jakob disease. Symptoms of such diseases include changes in memory, movement, intelligence, and behavior.