Anosognosia, completion and confabulation: The neutral-personal dichotomy

Unawareness of defects or anosognosia has been closely associated with confabulation in neurological patients. In order to understand better the relationship between anosognosia and confabulation we have reviewed a range of phenomena from perceptual completion to elaborate confabulations such as delusional misidentifications. Using this literature and an analysis of selected cases we propose that all confabulations can be grouped into two forms, neutral and personal, both of which may contribute to the production of anosognosia. Further, we suggest personal forms can be largely equated with the delusional misidentification syndromes with which they share a common neuroanatomy and similar mechanisms. We propose that some aspects of anosognosia can best be viewed as delusional misidentification of personal illness, which is associated with paralimbic, especially caudal orbitofrontal lesions. We further suggest a new term - Delusional Missociation Syndromes - to describe the perturbation in relatedness of the self seen in these forms of personal confabulation.