S100 is a family of small vertebrates, calcium-binding proteins. One of them is S100B protein, mostly in astrocytes. These cells are also a source of S100B released into the intercellular space. S100B protein involved in the regulation of many processes such as cytoskeletal protein phosphorylation, proliferation, and differentiation of cells. Conducted over 40 years, studies have shown that S100B has a positive effect on learning. But there is also evidence to suggest that excess S100B can lead to memory disorders. It is possible that increased S100B secretion by astrocytes may be jointly responsible for the memory deficits observed in the early stages of Alzheimer's disease.