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false belief based upon a misinterpretation of reality. It is not, like a hallucination, a false sensory perception, or like an illusion, a distorted perception. Delusions vary in intensity, and are not uncommon among substance abusers, particularly those who use amphetamines, cocaine, and hallucinogens. They also occur frequently among individuals who have been diagnosed with Alzheimer's diseaseAlzheimer's disease
, degenerative disease of nerve cells in the cerebral cortex that leads to atrophy of the brain and senile dementia and, ultimately, death. The disease is characterized by abnormal accumulation of plaques and by neurofibrillary tangles (malformed nerve
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, Huntington's diseaseHuntington's disease,
hereditary, acute disturbance of the central nervous system usually beginning in middle age and characterized by involuntary muscular movements and progressive intellectual deterioration; formerly called Huntington's chorea.
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, or schizophreniaschizophrenia
, group of severe mental disorders characterized by reality distortions resulting in unusual thought patterns and behaviors. Because there is often little or no logical relationship between the thoughts and feelings of a person with schizophrenia, the disorder has
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, and during the manic stage of bipolar disorder (see depressiondepression,
in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disorder, also called major depression, and bipolar disorder, whose sufferers are
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). Some common delusions include persecutory delusions, in which the individual falsely believes that others are plotting against him; delusions of thought broadcasting, where the individual believes his thoughts can be transmitted to others; delusions of thought insertion, in which the individual believes that thoughts are being implanted in his mind; and delusions of grandeur, in which the individual imagines himself an unappreciated person of great importance.


A conviction based on faulty perceptions, feelings, and thinking.


Borkman, John Gabriel
suffers from delusions of power. [Nor. Lit.: John Gabriel Borkman]
Bowles, Sally
night-club entertainer thinks she has the makings of a great film actress. [Br. Lit.: Isherwood Berlin Stories in Drabble, 498]
Clamence, Jean-Baptiste
living with his own good and evil. [Fr. Lit.: The Fall]
Dubois, Blanche
felt she and Mitch were above others. [Am. Lit.: A Streetcar Named Desire]
Jones, Brutus
self-styled island emperor experiences traumatic visions. [Am. Lit.: Emperor Jones]
Lockit, Lucy
steals jailer-father’s keys to free phony husband. [Br. Lit.: The Beggar’s Opera]
Pan, Peter
little boy, refuses to grow up; resides in Never Never Land. [Children’s Lit.: Peter Pan]
opium of the people
Marx’s classic metaphor for religion. [Ger. Hist.: Critique of Hegel’s “Philosophy of Right”]
hides head, thinking itself concealed. [Animal Symbolism: Brewer Dictionary, 788]


Psychiatry a belief held in the face of evidence to the contrary, that is resistant to all reason
References in periodicals archive ?
When she was discharged, she still had the delusion of "I am an angel because I don't have a gender" but it gradually disappeared with time.
However, in recent years, it is experiencing a historic moment: the end of delusions.
In these cases, any destabilization of the delusion might lead once again to distress and fear associated with anomalous perceptual experiences.
While The Disease Delusion excels at helping readers understand what's really behind their health woes, the book is light on what to do about it.
The Fregoli Delusion is all about delusion, reality, and a very real syndrome that affects a crime investigation and teaches the two investigators a thing or two about psychology: ""Fregoli syndrome is actually quite rare," Caldwell said.
Opinion polls show varied results and it creates delusion and misleads people.
It is far less frightening to fearfully lie (and act accordingly) than to acknowledge her delusion about herself and to accept responsibility for her dysfunctional and violent behaviors.
Another sufferer from this delusion is Willy Russell, who has continually stated (most recently on a screen in the Museum of Liverpool) that the theatre in Liverpool only started with himself and a few other local writers in the seventies.
Over the years, I have made peace with the ignorance and audacity of the average American, but hearing such drivel from the mouth of an individual who, supposedly by his position and title, must be better informed than the average guy in the street, made me realise delusions are a universal part of the human psyche.
If the Egyptians trade accusations of treason and continue to weave delusions over secret agreements and more, or boycott the presidential elections or promote the story of "remnants [of the former regime]" versus Islamists, rather than viewing this as being a choice between a civil state and religious state, then this -- unfortunately -- means that Egypt is on the verge of a severe setback and not a corrective movement
Khamenehi may still, however, be operating under a delusion about what Obama is saying.
We still bear the consequences from this delusion because the government, even the citizens, secretly wish or look for this opportunity.