Dementia isn't a specific disease. Instead, dementia describes a group of symptoms affecting memory, thinking and social abilities severely enough to interfere with daily functioning.
Dementia indicates problems with at least two brain functions, such as memory loss and impaired judgment or language, and the inability to perform some daily activities such as paying bills or becoming lost while driving.
Though memory loss generally occurs in dementia, memory loss alone doesn't mean you have dementia. There is a certain extent of memory loss that is a normal part of aging.
Many causes of dementia symptoms exist. Alzheimer's disease is the most common cause of a progressive dementia. Some causes of dementia may be reversible.