title: Body distortions in Anorexia Nervosa: Evidence for changed processing of multisensory bodily signals.
abstract: Body size and shape distortion is a core feature of Anorexia Nervosa (AN) - patients experience their body as fat while objectively being very thin. The cause of this distortion is unclear and disturbances in body perception could be involved. Body perception comprises estimating shape and location of one's body and requires integrating multisensory signals. We investigated if and how body location perception is changed and tested 23 AN patients and 23 healthy controls (HC) in a Rubber Hand Illusion (RHI) reaching paradigm. We presented two types of multisensory conflicts (visual-proprioceptive hand location; visual-tactile touch synchrony) and tested if the impact of visual-proprioceptive and visual-tactile signals on hand location perception differs between AN and HC groups. We found significant group differences in shifts of reaching trajectories, indicating that the influence of proprioceptive signals on hand location estimates is reduced in AN. Hand location estimates were relatively more biased towards external visual information, and shorter illness durations predicted a larger visual bias. Although touch synchrony also significantly influenced hand location estimates, this effect did not differ between groups. Our findings provide compelling evidence that multisensory body location perception - specifically the processing of visual-proprioceptive signals - is changed in AN.
authors.affiliation: Perception in Action Research Centre & Department of Cognitive Science, Faculty of Human Sciences, Macquarie University & ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia. Electronic address: Regine.Zopf@mq.edu.au.
authors.forename: Regine
authors.initials: R
authors.lastname: Zopf
authors.affiliation: Perception in Action Research Centre & Department of Cognitive Science, Faculty of Human Sciences, Macquarie University & ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia.
authors.forename: Erika
authors.initials: E
authors.lastname: Contini
authors.affiliation: Wesley Eating Disorder Centre, Wesley Hospital, Sydney, Australia.
authors.forename: Chris
authors.initials: C
authors.lastname: Fowler
authors.affiliation: Eating Disorder Unit, Northside Hospital, Sydney, Australia.
authors.forename: Naresh
authors.initials: N
authors.lastname: Mondraty
authors.affiliation: Perception in Action Research Centre & Department of Cognitive Science, Faculty of Human Sciences, Macquarie University & ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Williams
mesh_terms: D000328:Adult; D000856:Anorexia Nervosa / Q000523:psychology*; D057215:Body Dysmorphic Disorders / Q000523:psychology; D001828:Body Image / Q000523:psychology*; D016022:Case-Control Studies; D005260:Female; D006225:Hand; D006801:Humans; D007088:Illusions; D010469:Perceptual Distortion; D010812:Physical Stimulation / Q000379:methods; D011434:Proprioception; D012408:Rubber; D014110:Touch; D055698:Touch Perception; D014796:Visual Perception; D055815:Young Adult
chemical_list: D012408:Rubber
keywords: Anorexia Nervosa; Body perception; Hand location; Multisensory; Proprioception; Reaching; Rubber hand illusion paradigm