Dementia

Dementia is a description of the state of a person's mental functioning and not a specific disease. Dementia involves a decline in mental function from a previously higher level, severe enough to interfere with daily life. A person with dementia has two or more of these specific difficulties. Dementia develops when parts of the brain responsible for learning, memory, decision-making, or language are affected by infection or disease. The most common cause of dementia is Alzheimer's disease.