(Science: neurology, psychiatry) An organic mental disorder characterised by a general loss of intellectual abilities involving impairment of memory, judgment and abstract thinking as well as changes in personality.
It does not include loss of intellectual functioning caused by clouding of consciousness (as in delirium) nor that caused by depression or other functional mental disorder (pseudodementia). Dementia may be caused by a large number of conditions, some reversible and some progressive, that cause widespread cerebral and damage or dysfunction. The most common cause is alzheimers disease, others are cerebrovascular disease (multi infarct dementia), central nervous system infection, brain trauma or tumours, pernicious anaemia, folic acid deficiency, Wernicke Korsakoff syndrome, normal pressure hydrocephalus, and, neurological diseases such as huntington disease, multiple sclerosis and parkinsons disease.
Origin: L. Mens = mind