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The loss, usually progressive, of cognitive and intellectual functions, without impairment of perception or consciousness; caused by a variety of disorders including severe infections and toxins, but most commonly associated with structural brain disease. Characterized by disorientation, impaired memory, judgment, and intellect, and a shallow labile affect. SYN: amentia (2). [L. fr. de- priv. + mens, mind]
- catatonic d. d. with catatonic symptoms.
- epileptic d. d. occurring in an individual afflicted with epilepsy, and thought to be a result of prolonged seizures, the epileptogenic brain lesion, or antiepileptic drugs.
- hebephrenic d. d. with hebephrenic symptoms.
- paralytic d. d. and paralysis resulting from a chronic syphilitic meningoencephalitis. SYN: d. paralytica.
- d. paralytica SYN: paralytic d..
- d. praecox any one of the group of psychotic disorders known as the schizophrenias; formerly used to describe schizophrenia as a single entity. [L. precocious]
- presenile d., d. presenilis 1. d. of Alzheimer disease developing before age 65; 2. SYN: Alzheimer disease.
- secondary d. chronic d. following and due to a psychosis or some other underlying disease process.
- vascular d. a steplike deterioration in intellectual functions with focal neurologic signs, as the result of multiple infarctions of the cerebral hemispheres. SYN: multi- infarct d..
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de·men·tia di-'men-chə n a usu. progressive condition (as Alzheimer's disease) marked by the development of multiple cognitive deficits (as memory impairment, aphasia, and inability to plan and initiate complex behavior)
de·men·tial -chəl adj
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n.
a chronic or persistent disorder of behaviour and higher intellectual function due to organic brain disease. It is marked by memory disorders, changes in personality, deterioration in personal care, impaired reasoning ability, and disorientation. Presenile dementia occurs in young or middle-aged people. The most common causes of dementia are Alzheimer's disease, frontotemporal dementia (e.g. Pick's disease), and dementia due to diffuse cortical Lewy body disease. Another common form, multi-infarct dementia, results from the destruction of brain tissue by a series of small strokes. It is important to distinguish these organic conditions from psychological disorders that cause the same symptoms (see pseudodementia).
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de·men·tia (də-menґshə) [de- + L. mens mind] [DSM-IV] a general loss of cognitive abilities, including impairment of memory as well as one or more of the following: aphasia, apraxia, agnosia, or disturbed planning, organizing, and abstract thinking abilities. It does not include loss of intellectual functioning caused by clouding of consciousness (as in delirium), depression, or other functional mental disorder (pseudodementia). Causes include a large number of conditions, some reversible and some progressive, that result in widespread cerebral damage or dysfunction. The most common cause is Alzheimer disease; others include cerebrovascular disease, central nervous system infection, brain trauma or tumors, vitamin deficiencies, anoxia, metabolic conditions, endocrine conditions, immune disorders, prion diseases, Wernicke-Korsakoff syndrome, normal-pressure hydrocephalus, Huntington chorea, multiple sclerosis, and Parkinson disease.Medical dictionary. 2011.