Global brain atrophy (Human Phenotype Ontology term HP_0002283) is unlocalized atrophy of the brain with decreased total brain matter volume and increased ventricular size. Also known as: Diffuse brain atrophy, Generalised brain atrophy, Generalised brain degeneration, Generalised cerebral atrophy, Generalized brain atrophy, Generalized brain degeneration, Generalized cerebral atrophy.