Nosological and Aetiological Aspects of Misidentification Symptoms
Stein Opjordsmoen, Nils Retterstøl Department of Psychiatry, Ullevål University Hospital University of Oslo Oslo, Norway
Delusional Misidentification Syndromes (DMS)
Belief in duplicates and replacements
(Christodoulou & Malliara-Loulakaki, 1981)
DMS
1. 2. Capgras delusion Frégoli delusion
3. 4.
Intermetamorphosis delusion Subjective doubles delusion
1, 2 and 3: Delusion containing a non–self person 4: Doppelgänger Syndrome-delusion referring to the person’s own self
(Christodoulou & Malliara-Loulakaki, 1981; Ellis et al., 1994)
DMS
Different modalities of duplicates/replacements
• • • • • • Person Self Parts of the body Objects Place Time and event
A continuum of misidentification symptoms Differentiation of inappropriate familiarity based on the severity of disturbance of reality testing, as measured by its intensity, duration and pervasiveness
(Sno, 1994)
Is misidentification
• A delusion? • A perceptual disturbance? • A cognitive dysfunction?
- (perception of changed environment misinterpreted as delusional misidentification) - (defective boundaries between the individual and the outer world)
DMS
Psychodynamic Organic
• Projection • Splitting of internalised object representation • Regression • Ambivalence • Symbolic aspects • Adaptive aspects • Altered face recognition processing • Frontal lobe abnormalities • Temporal lobe abnormalities • Right hemisphere dysfunction • Disorders of memory • Impaired connectivity
DMS and nosology
• • • • schizophrenia other psychoses paranoia/delusional disorder? organic [toxic, functional impairment (schizophrenia?), structural abnormalities]
Conclusion on status of DMS
• Some obviously organic • Some obviously functional (?) • Many somewhere in between with interplay between individual psychology, cognition and perception
- Heterogeneous neuropsychiatric conditions