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Key Terms

anosognosia
not having insight or awareness into disease
auditory hallucination
altered perception of hearing in the absence of external stimuli
bizarre delusion
fixed false beliefs with content that is not reasonably possible in this world
cognitive symptoms
deficits in ability to think or reason
delusion
fixed false belief that cannot be changed in the mind of those who hold them despite evidence to the contrary
formication
hallucination that bugs are crawling on the skin
gustatory hallucination
false perception involving taste
hallucination
perception of sensory experiences without natural external stimuli, including auditory, visual, tactile, gustatory, and olfactory types
negative symptoms
“take away” from a person’s personality, including cognitive decline and apathy
non-bizarre delusion
fixed false belief containing content that is plausible but inconsistent with evidence
olfactory hallucination
false sensory experience involving the sense of smell
positive symptoms
changes to behaviors or content of thought, or the presence of symptoms, including hallucinations and delusions
psychosis
severe mental condition where a person loses the ability to recognize reality or has lost contact with external reality, causing a loss of function and disorganization of personality
schizophrenia
severe mental illness and disturbance involving a collection of cognitive, affective, and behavioral symptoms that negatively impact social, educational, or occupational functioning
tactile hallucination
false sensory perceptions involving the sense of touch
visual hallucination
false sensory experience that is seen
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