title: Using theories of delusion formation to explain abnormal beliefs in Body Dysmorphic Disorder (BDD).
abstract: Body Dysmorphic Disorder (BDD) is characterised by overvalued or delusional beliefs of 'imagined ugliness'. Delusional beliefs have been explained by a number of cognitive theories, including faulty perceptions, biases in attention, and corruption of semantic memory. Atypical aesthetics may also influence beliefs in BDD. In fourteen BDD patients, compared to controls (n=14), we examined these theories of beliefs in a cognitive test battery consisting of perceptual organisation and visual affect perception tasks, a Stroop task using body words, a sentence verification task, a fluency task, and an attractiveness task. BDD patients performed similar to controls on tasks measuring information (bias) processing and aesthetics. However, BDD showed abnormal abilities on semantic processing involving sentence verification and category fluency. There was only a trend finding of impaired performance on perceptual processing tasks in BDD. The findings suggest that the delusional beliefs in BDD may be explained by impaired semantic processing.
authors.affiliation: Brain and Psychological Sciences Research Centre, Faculty of Life and Social Sciences, Swinburne University of Technology, Melbourne, Australia; Monash Alfred Psychiatry research centre (MAPrc), The Alfred Hospital and Monash University Central Clinical School, 607 St Kilda Rd, Melbourne, Australia; Departments of Behavioural Science and Psychiatry, University of Melbourne, Melbourne, Australia; Department of Psychiatry, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Susan L
authors.initials: SL
authors.lastname: Rossell
authors.affiliation: School of Psychological Sciences, Faculty Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia. Electronic address: izelle.labuschagne@monash.edu.
authors.forename: Izelle
authors.initials: I
authors.lastname: Labuschagne
authors.affiliation: Departments of Behavioural Science and Psychiatry, University of Melbourne, Melbourne, Australia.
authors.forename: Judy
authors.initials: J
authors.lastname: Dunai
authors.affiliation: Brain and Psychological Sciences Research Centre, Faculty of Life and Social Sciences, Swinburne University of Technology, Melbourne, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Kyrios
authors.affiliation: Departments of Behavioural Science and Psychiatry, University of Melbourne, Melbourne, Australia; Department of Psychiatry, St Vincent's Hospital, Melbourne, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Castle
mesh_terms: D000328:Adult; D001288:Attention; D057215:Body Dysmorphic Disorders / Q000523:psychology*; D001828:Body Image / Q000523:psychology*; D016022:Case-Control Studies; D003702:Delusions / Q000523:psychology*; D005260:Female; D006801:Humans; D007092:Imagination; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012649:Self Concept
keywords: Body Dysmorphic Disorder; Cognition; Delusions; Perception; Semantics