title: Ownership illusions in patients with body delusions: Different neural profiles of visual capture and disownership.
abstract: The various neurocognitive processes contributing to the sense of body ownership have been investigated extensively in healthy participants, but studies in neurological patients can shed unique light into such phenomena. Here, we aimed to investigate whether visual capture by a fake hand (without any synchronous or asynchronous tactile stimulation) affects body ownership in a group of hemiplegic patients with or without disturbed sensation of limb ownership (DSO) following damage to the right hemisphere. We recruited 31 consecutive patients, including seven patients with DSO. The majority of our patients (64.5% overall and up to 86% of the patients with DSO) experienced strong feelings of ownership over a rubber hand within 15 sec following mere visual exposure, which correlated with the degree of proprioceptive deficits across groups and in the DSO group. Using voxel-based lesion-symptom mapping analysis, we were able to identify lesions associated with this pathological visual capture effect in a selective fronto-parietal network, including significant voxels (p < .05) in the frontal operculum and the inferior frontal gyrus. By contrast, lesions associated with DSO involved more posterior lesions, including the right temporoparietal junction and a large area of the supramarginal gyrus, and to a lesser degree the middle frontal gyrus. Thus, this study suggests that our sense of ownership includes dissociable mechanisms of multisensory integration.
authors.affiliation: Department of Neurology, Rouen University Hospital, France; Clinical, Educational & Health Psychology Research Department, Division of Psychology & Language Sciences, University College London, UK.
authors.forename: Olivier
authors.initials: O
authors.lastname: Martinaud
authors.affiliation: Clinical, Educational & Health Psychology Research Department, Division of Psychology & Language Sciences, University College London, UK; Academic Unit of Neuropsychiatry, King's College London, UK.
authors.forename: Sahba
authors.initials: S
authors.lastname: Besharati
authors.affiliation: School of Life and Medical Sciences, University of Hertfordshire, UK.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Jenkinson
authors.affiliation: Clinical, Educational & Health Psychology Research Department, Division of Psychology & Language Sciences, University College London, UK. Electronic address: a.fotopoulou@ucl.ac.uk.
authors.forename: Aikaterini
authors.initials: A
authors.lastname: Fotopoulou
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001828:Body Image / Q000523:psychology*; D003702:Delusions / Q000523:psychology*; D005260:Female; D006801:Humans; D007088:Illusions / Q000523:psychology*; D065812:Interoception / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000209:etiology / Q000523:psychology*; D011434:Proprioception / Q000502:physiology*; D020521:Stroke / Q000150:complications; D014796:Visual Perception / Q000502:physiology
keywords: Anosognosia for hemiplegia; Asomatognosia; Insula; Interoception; Motor awareness; Premotor cortex; Proprioception; Rubber hand illusion; Sense of body ownership; Visual capture