Dementia

Dementia (from Latin de- "apart, away" + mens (genitive mentis) "mind") is the progressive decline in cognitive function due to damage or disease in the brain beyond what might be expected from normal aging.

Particularly affected areas may be memory, attention, language, and problem solving. Especially in the later stages of the condition, affected persons may be disoriented in time (not knowing what day of the week, day of the month, month, or even what year it is), in place (not knowing where they are), and in person (not knowing who they are).

Symptoms of dementia can be classified as either reversible or irreversible depending upon the etiology of the disease. Less than 10% of cases of dementia have been reversed. Dementia is a non-specific term encompassing many disease processes, just as fever is attributable to many etiologies.

Without careful assessment, delirium can easily be confused with dementia and a number of other psychiatric disorders because many of the signs and symptoms are also present in dementia (as well as other mental illnesses including depression and psychosis)
Sources: Wikipedia | Starbulletin
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