Delusions of Misidentification Flashcards
Delusion
A fixed belief that is not amenable to change in light of conflicting evidence.
Three features of delusions
Run counter to beliefs held by others within the same socio-cultural environment, defy rational counter-argument, are maintained despite overwhelming counter evidence.
Delusions of misidentification
Disorders in which there is a mistaken belief in the identity of oneself, other people, places or objects.
Capgras Syndrome
The belief that a person, usually closely related to the patient, has been replaced by imposter(s) with a close resemblance to the original(s).
Capgras case - de Bruxelles (1999) reported
Following a car crash Alan Davies became convinced that his wife of 31 years died in the accident and had been replaced by someone with whom he did not want to share his life.
Capgras case - de Pauw & Szilecka (1988)
A young man w/ Capgras syndrome decapitated his stepfather to look for batteries and microfilm as he believed he was a robot replacing his stepfather.
Capgras - Forstl et al (1991)
Only 18% of 260 cases of Capgras’ syndrome noted physical violence.
Fregoli Syndrome
The belief that strangers are in fact known people in disguise - a person who is well known to the patient is actually pretending to take on the appearance of a stranger.
de Pauw et al (1987)
A woman who suffered a right temporo-parietal infarct was convinced she was pursued by a disguised cousin and his female accomplice - she was committed to a hospital for her own safety after she started haranguing passers by who she accused of being them.
Fregoli case - Ruff & Volpe (1981)
A woman who after the removal of a subdural haematoma, claimed that the patient in the bed next to her was her husband.
Fregoli case - Feinberg et al. (1999)
A man developed numerous Fregoli-type misidentifications after suffering a traumatic brain injury with right frontal and left temporoparietal contusions.
Intermetamorphosis
The belief that someone has changed physically and psychologically into another person.
Intermetamorphosis case - Courbon & Tusques (1932)
A 49 year old woman who claimed that objects and animals seemed altered. People could change gender as she looked at them. Many people looked like her son and aunt. She could distinguish them from her true son only by examining their feet.
Reverse intermetamorphosis
The belief that there has been a change of oneself into another person.
Reverse intermetamorphosis case - Breen et al. (2000)
A woman who had the delusional belief hat she was her father and occasionally her grandfather. She would only respond to her fathers name and signed his name when asked to sign forms. She consistently gave her fathers history when questioned about her personal history.
