Capgras delusion
psychiatric disorder (syndrome) in which a person holds a delusion that a family member has been replaced by an identical imposter
Capgras delusion or Capgras syndrome (CS) is a psychiatric disorder in which a person holds a delusion that a friend, spouse, parent, other close family member, or pet has been replaced by an identical impostor. It is named after Joseph Capgras (1873–1950), the French psychiatrist who first described the disorder.
The Capgras delusion is classified as a delusional misidentification syndrome, a class of beliefs that involves the misidentification of people, places, or objects. It can occur in acute, transient, or chronic forms. Cases in which patients hold the belief that time has been "warped" or "substituted" have also been reported.
The delusion most commonly occurs in individuals diagnosed with a psychotic disorder, usually schizophrenia; it has also been seen in brain injury, dementia with Lewy bodies, and other forms of dementia. It presents often in individuals with a neurodegenerative disease, particularly at an older age; it has also been reported as occurring in association with diabetes, hypothyroidism, and migraine attacks. In one isolated case, the Capgras delusion was temporarily induced in a healthy subject by administration of ketamine. It occurs 50% more frequently in females when compared to males.
History
Capgras syndrome is named after Joseph Capgras, a French psychiatrist who first described the disorder in 1923 in his paper co-authored by Jean Reboul-Lachaux.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 6, 2026. The linked authority identifier is Q838018. The Library of Congress control number is sh2005005156. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1873, 1950 and 1923.
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This entry incorporates text from “Capgras delusion” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.