Reduplicative Paramnesia

Reduplicative paramnesia is a delusional misidentification syndrome in which a person believes that a familiar place, most often their own home or the hospital in which they are being treated, has been duplicated, so that it now exists simultaneously in two or more separate locations, or has been physically relocated to a different site than where it actually stands. The Swiss neurologist Arnold Pick provided one of the earliest detailed clinical descriptions of the phenomenon in the late nineteenth century, working with patients who had sustained significant brain damage. The condition is strongly associated with organic neurological injury, particularly damage involving the right cerebral hemisphere and the frontal lobes, and is most often observed in patients with dementia, following a stroke, or after traumatic brain injury, though isolated cases have also been reported in primary psychiatric illness. Clinicians and researchers generally group reduplicative paramnesia together with other delusional misidentification syndromes, including Capgras delusion and Fregoli delusion, both already documented elsewhere in this section, since all three share an underlying disruption in how the brain integrates familiarity and identity, whether of a person or of a place, with the correct, single real-world referent for that familiar thing. Unlike a simple confusion or memory lapse, the belief in reduplicative paramnesia tends to be firmly and persistently held even when the person is shown direct evidence, such as being taken to see that only one version of the place actually exists.