Prosopagnosia and the Delusional Misidentification Syndromes

Delusions of Transformation of the Self

“…Findings regarding radical facial changes suggest that in these patients facial recognition deficits may develop especially when strong affective mechanisms are associated with certain ob jects (i.e., the self or significant other). Our findings, which are suggestive of serious facial misrecognition in syndromes of the self are also consistent with previous studies of misidentification syndromes of others which show that many of these patients suffer from facial recognition deficits as suggested by neu ropsychological testing [31,32], Facial recog nition processing is associated with nondomi nant cerebral function [33], The frequent finding that misidentification syndromes are associated with nondominant hemisphere dysfunction lends support to the idea that misidentification syndromes are at least par tially caused by cerebral deficits associated with facial processing and other forms of topographical processing [31,32,34].…”

The Delusional Misidentification Syndromes

“…MMPI eva lua tions reveal significa nt d epression , paranoia , isolation a nd co nst ricted expression of e mo tio ns (36) . Rorsch ach testing shows unu su al expe rie nces of th e e nviro nme n t (37); respo nses are d et e rmined by sm all det ail s of th e pictures (p iecemea l-st yle perception), whi ch suggests th e presen ce of right hemispheric a nd front al lobe dysfuncti on (38).…”

What Is Meant by ‘Misidentification’ in Delusional Misidentification Syndromes?

“…After the first description of CS by Capgras and ReboulLachaux [5], the syndrome was mainly discussed as a psychiatric condition, in contrast to reduplicative paramnesia, which is always discussed as a neurologic symptom. Recently, however, some authors have suspected an organic etiology of CS especially in relation to prosopagnosia [6]. Although CS might partly be explicable in terms of a dysfunction of higher visual information processing, in some patients who explicitly insist that the impostor resembles the original exactly the syndrome cannot be explained by a dysfunction of (at least overt) visual information processing.…”