Pathogenesis of reduplicative paramnesia.

The incidence of reduplicative paramnesia was sampled with a structured interview in 50 consecutive alcoholic inpatients. Four had reduplicative paramnesia (RP group) and 46 did not (non-RP group). Three of four patients in RP group had acute right hemispheric lesions and none had a left hemispheric lesion; 19 non-RP patients had left hemispheric lesions, 2 had right, and 25 had none. These data are in keeping with the previous suggestions that the neuroanatomical basis for reduplicative paramnesia is an acute right hemispheric lesion superimposed on chronic diffuse or bifrontal deficit.