title: Sensations of skin infestation linked to abnormal frontolimbic brain reactivity and differences in self-representation.
abstract: Some patients experience skin sensations of infestation and contamination that are elusive to proximate dermatological explanation. We undertook a functional magnetic resonance imaging study of the brain to demonstrate, for the first time, that central processing of infestation-relevant stimuli is altered in patients with such abnormal skin sensations. We show differences in neural activity within amygdala, insula, middle temporal lobe and frontal cortices. Patients also demonstrated altered measures of self-representation, with poorer sensitivity to internal bodily (interoceptive) signals and greater susceptibility to take on an illusion of body ownership: the rubber hand illusion. Together, these findings highlight a potential model for the maintenance of abnormal skin sensations, encompassing heightened threat processing within amygdala, increased salience of skin representations within insula and compromised prefrontal capacity for self-regulation and appraisal.
authors.affiliation: Department of Psychiatry, Brighton and Sussex Medical School, UK; Sussex Partnership Foundation NHS Trust, UK. Electronic address: j.eccles@bsms.ac.uk.
authors.forename: J A
authors.initials: JA
authors.lastname: Eccles
authors.affiliation: Department of Psychiatry, Brighton and Sussex Medical School, UK; Sackler Centre for Consciousness Science, University of Sussex, UK.
authors.forename: S N
authors.initials: SN
authors.lastname: Garfinkel
authors.affiliation: Department of Psychiatry, Brighton and Sussex Medical School, UK; Sussex Partnership Foundation NHS Trust, UK; Sackler Centre for Consciousness Science, University of Sussex, UK.
authors.forename: N A
authors.initials: NA
authors.lastname: Harrison
authors.affiliation: Sackler Centre for Consciousness Science, University of Sussex, UK; School of Psychology, University of Sussex, UK.
authors.forename: J
authors.initials: J
authors.lastname: Ward
authors.affiliation: Queen Mary University of London, UK; Department of Dermatology, Barts and the London NHS Trust, London, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Taylor
authors.affiliation: Department of Dermatology, Barts and the London NHS Trust, London, UK.
authors.forename: A P
authors.initials: AP
authors.lastname: Bewley
authors.affiliation: Department of Psychiatry, Brighton and Sussex Medical School, UK; Sussex Partnership Foundation NHS Trust, UK; Sackler Centre for Consciousness Science, University of Sussex, UK.
authors.forename: H D
authors.initials: HD
authors.lastname: Critchley
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D006225:Hand / Q000503:physiopathology; D006801:Humans; D007088:Illusions / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010465:Perception / Q000502:physiology*; D010775:Photic Stimulation; D012677:Sensation / Q000502:physiology; D012876:Skin Diseases, Parasitic / Q000503:physiopathology* / Q000523:psychology*; D012879:Skin Physiological Phenomena; D013001:Somatoform Disorders / Q000503:physiopathology*; D014796:Visual Perception / Q000502:physiology
keywords: Delusional infestation; Interoception; Neuroimaging; Psychodermatology; Rubber hand illusion