title: Neural basis of limb ownership in individuals with body integrity identity disorder.
abstract: Our body feels like it is ours. However, individuals with body integrity identity disorder (BIID) lack this feeling of ownership for distinct limbs and desire amputation of perfectly healthy body parts. This extremely rare condition provides us with an opportunity to study the neural basis underlying the feeling of limb ownership, since these individuals have a feeling of disownership for a limb in the absence of apparent brain damage. Here we directly compared brain activation between limbs that do and do not feel as part of the body using functional MRI during separate tactile stimulation and motor execution experiments. In comparison to matched controls, individuals with BIID showed heightened responsivity of a large somatosensory network including the parietal cortex and right insula during tactile stimulation, regardless of whether the stimulated leg felt owned or alienated. Importantly, activity in the ventral premotor cortex depended on the feeling of ownership and was reduced during stimulation of the alienated compared to the owned leg. In contrast, no significant differences between groups were observed during the performance of motor actions. These results suggest that altered somatosensory processing in the premotor cortex is associated with the feeling of disownership in BIID, which may be related to altered integration of somatosensory and proprioceptive information.
authors.affiliation: Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands ; Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, New York, United States of America.
authors.forename: Milenna T
authors.initials: MT
authors.lastname: van Dijk
authors.forename: Guido A
authors.initials: GA
authors.lastname: van Wingen
authors.forename: Anouk
authors.initials: A
authors.lastname: van Lammeren
authors.forename: Rianne M
authors.initials: RM
authors.lastname: Blom
authors.forename: Bart P
authors.initials: BP
authors.lastname: de Kwaasteniet
authors.forename: H Steven
authors.initials: HS
authors.lastname: Scholte
authors.forename: Damiaan
authors.initials: D
authors.lastname: Denys
mesh_terms: D000328:Adult; D001828:Body Image; D001921:Brain / Q000503:physiopathology; D005121:Extremities / Q000294:innervation*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology; D009415:Nerve Net / Q000503:physiopathology; D009420:Nervous System / Q000503:physiopathology*; D010296:Parietal Lobe / Q000503:physiopathology; D011597:Psychomotor Performance / Q000502:physiology; D020886:Somatosensory Disorders / Q000503:physiopathology*; D014110:Touch; D055815:Young Adult