Introduction and aims: Features of the Capgras delusion, the most common among the delusional misidentification syndromes, are reviewed. We describe its phenomenology in psychiatric and organic diseases, its prevalence and comorbidity with other reduplicative disorders and review aetiological models in order to elucidate the origins of the delusion from both the cognitive psychology and psychodynamics precepts, as the neuropsychiatry and anatomical basis.
Development: According to cognitive models, Capgras syndrome cannot be exclusively conceived as a dysfunction in facial recognition but in recognizing a person globally considered. Feeling of familiarity is absent due to the inability to integrate successive memories about a person along episodic experiences, thus generating delusional doubles in accordance to the patient's needs or drives. From the neuropsychiatry point of view Capgras delusion arises from the failure in reconciling information about identification of the person and its associated emotions by the disconnection between frontal lobes and right temporo-limbic regions (hippocampus), in addition to bilateral frontal damage. Delusions are more commonly associated with right hemisphere lesions because of the impairment of several functions such as self monitoring, reality monitoring, memory and feelings of familiarity as well as the necessary preservation of the left hemisphere.
Conclusions: Aetiology of Capgras delusion should include the conjoint involvement of clinical, neuropsychiatric and neuropsychological data with different theoretical models.