Abstract
Objective:
Reduplicative paramnesia (RP) is thought to be related to other delusional misidentification syndromes (DMS) such as Capgras syndrome. DMS are thought to occur when brain lesions disrupt cortical functioning. This study tests this hypothesis and tries to understand whether focal lesions are as important in the etiology of RP as they are in other types of DMS.
Method:
The computed tomography (CT) scans of 10 consecutive psychiatric inpatients with RP and another principal psychiatric diagnosis were compared with those of control patients without RP matched for age, sex, and principal psychiatric diagnosis. The scans were assessed blindly by a neuroradiologist using a previously published rating scale for the presence of lesions in 11 discrete anatomic areas. The differences between the 2 groups were examined statistically using log-linear analysis.
Results:
Statistical analysis revealed that index patient cortical atrophy, cortical fissure enlargement, and deep brain atrophy distinguished the 2 groups significantly (P < 0.05).
Conclusions:
Bilateral anterior cortical, brain stem, and cerebellar vermis atrophy and dysfunction may be important in the pathogenesis of RP in particular and of DMS in general.