Reduplicative paramnesia: longitudinal neurobehavioral and neuroimaging analysis.

Reduplicative paramnesia (RP) is a delusion in which the patient perceives familiar places, objects, or events to have been duplicated. The current case describes the development of RP in an 81-year-old male following a large right frontal lobe infarction. As the patient had been hospitalized previously with hemorrhagic contusions, neurologic, neuropsychological, and neuroimaging data were obtained both prior to and following RP onset. Psychophysiologic data were obtained following the development of the delusion. Both premorbidly and at follow-up, neuropsychological functioning was characterized by significant impairments of learning and memory and frontal-executive functions. Language and visuospatial skills and motor speed were intact both before and after RP onset. The case is described within the context of preexisting theories of RP, and it is surmised that the delusion is secondary to temporal-limbic-frontal dysfunction giving rise to a distorted sense of familiarity and impaired ability to resolve the delusion via reasoning.