title: Isolated prospective confabulation in Wernicke-Korsakoff syndrome: a case for reality filtering.
abstract: A 57-year-old man suffered severe amnesia and disorientation, accompanied by content-specific confabulation, due to an alcoholic Wernicke-Korsakoff syndrome. For months, he was deeply concerned about a single obligation that he thought he had to respond to, but which he had already assumed 20 years previously. This monothematic, prospective confabulation was associated with failures of reality filtering as previously documented in behaviorally spontaneous confabulation and disorientation: the patient failed to suppress the interference of currently irrelevant memories and to abandon anticipations that were no longer valid (impaired extinction capacity). Magnetic resonance imaging showed damage to the mamillary bodies and the dorsomedial thalamic nucleus. Positron emission tomography (FDG-PET) showed extended orbitofrontal hypometabolism. We suggest that isolated prospective confabulation shares the core feature (acts and thoughts based on currently irrelevant memory), mechanism (failure of reality filtering), and anatomical basis (orbitofrontal dysfunction) with behaviorally spontaneous confabulations.
authors.affiliation: Laboratory of Cognitive Neurorehabilitation, Department of Clinical Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland. armin.schnider@hcuge.ch
authors.forename: Armin
authors.initials: A
authors.lastname: Schnider
authors.forename: Louis
authors.initials: L
authors.lastname: Nahum
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Pignat
authors.forename: Béatrice
authors.initials: B
authors.lastname: Leemann
authors.forename: Karl-Olof
authors.initials: KO
authors.lastname: Lövblad
authors.forename: Michael
authors.initials: M
authors.lastname: Wissmeyer
authors.forename: Radek
authors.initials: R
authors.lastname: Ptak
mesh_terms: D000437:Alcoholism / Q000150:complications / Q000523:psychology; D001921:Brain / Q000473:pathology; D003702:Delusions / Q000523:psychology* / Q000534:rehabilitation; D005108:Extinction, Psychological; D019788:Fluorodeoxyglucose F18; D006801:Humans; D020915:Korsakoff Syndrome / Q000473:pathology / Q000523:psychology* / Q000534:rehabilitation; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D061212:Memory, Episodic; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D011597:Psychomotor Performance / Q000502:physiology; D019275:Radiopharmaceuticals / Q000378:metabolism; D057190:Stroop Test; D014706:Verbal Learning; D014888:Wechsler Scales
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18