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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 ?
3) The submissive father accepted the patient's delusions rather than risk jeopardising their relationship.
Challenging a patient regarding their delusions is likely pointless, as the patients' minds cannot be changed.
12] We are reporting a case of a young man developing a primary delusion in the backdrop of general Lok Sabha election against a national leader thus depicting the role of socio-demographic background influencing the onset of primary delusion.
This 50-year-old female had experienced seizures for 10 years and developed manic-like symptoms, delusions of jealousy, persecution and being watched, auditory hallucinations, irritable mood, and violent and disorganized behavior for the past 3 years.
delusion of hermaphroditism (one has merged in the same body with another person of the opposite sex)
He reported that his organs were destroyed, that he was hollow inside, and that he was a rotten and smelly flesh (negation delusion regarding the body, including the organs).
An individual lacking capacity can never be subject to an insane delusion or undue influence because those doctrines describe invalidating circumstances on all, or portions, of an otherwise valid will; the doctrines of insane delusions and undue influence apply to wills executed by a testator with capacity.
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.
Safety behaviors are thus reinforced, leading to maintenance and even support of delusion.
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.
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.