In layman’s terms, dementia is a description of a person who is dull and stupid. The medical definition of dementia is a syndrome of acquired, progressive intellectual disability. It refers to a state in which a person’s intelligence develops to a normal level and then declines for a variety of reasons, affecting daily living, social and work abilities. Dementia is usually characterized by memory loss, decreased language function, decreased ability to visually perceive spatial location and determine orientation, and often personality changes, behavioral aberrations and emotional abnormalities. Although the elderly person with dementia is generally awake, he or she is unable to recognize and remember information in the environment and respond normally accordingly. Alzheimer’s is not a single disease; it has a variety of causes and can be described as a large family. The number one member of this family is Alzheimer’s disease dementia, also known as senile dementia, which is a type of degenerative brain degeneration. Other common types of dementia include vascular dementia, Lewy body dementia, frontotemporal dementia, and others. In short, dementia is a group of syndromes with multiple etiologies leading to similar clinical manifestations.