Reduplicative misidentifications syndromes (RMS) are rare memory disorders characterized by the subjective conviction that
a place, person or event is duplicated. Even if RMS often follow a right frontal lesion, several studies have stressed the
importance of bilateral hemispheric pathology. Moreover, from a psychological perspective, there is uncertainty if this symptom
should be considered just as a kind of confabulation or if it should be associated with personal psychosocial and behavioral
aspects. We report a patient who developed normal pressure hydrocephalus and RMS one year after a post-traumatic right frontal
lesion. At the first neuropsychological evaluation, we found mild impairment of all function, associated with the presence
of reduplicative paramnesia. After the ventricle-peritoneal shunt intervention, we observed a progressive improvement of all
functions but the frontal ones. The memory deficit became less specific and the RMS disappeared. We therefore postulate that
a focal right frontal lesion is not sufficient to cause RMS per se. Our clinical report suggests that paramnesic events held
on reasonable ground, not being just a kind of confabulation.
Key words Reduplicative misidentification syndromes - Memory disorders - Focal brain damage
Received: 22 May 2000 / Accepted in revised form: 17 November 2000