An alteration in mental status refers to general changes in brain function, such as confusion, amnesia (memory loss), loss of alertness, loss of orientation (not cognizant of self, time, or place), defects in judgment or thought, poor regulation of emotions, and disruptions in perception, psychomotor skills, and behavior. While an altered mental status is obviously characteristic of a number of psychiatric and emotional conditions, medical conditions and injuries that cause damage to the brain can also cause mental status changes. Confusion, lethargy, delirium, dementia, encephalopathy, and organic brain syndrome are all terms that have been used to refer to conditions hallmarked by mental status changes.
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