Merel Prikken, PhD; Anouk van der Weiden, PhD; Heleen Baalbergen, MSc; Manon H.J. Hillegers, MD, PhD; René S. Kahn, MD, PhD; Henk Aarts, PhD; Neeltje E.M. van Haren, PhD
Background: Schizophrenia is a disorder of basic self-disturbance. Evidence suggests that people with schizophrenia may have aberrant experiences of body ownership: they may feel that they are not the subject of their own body experiences. However, little is known about the development of such disturbances.
Methods: Using a rubber hand illusion paradigm, we assessed body ownership in patients with schizophrenia (n = 54), healthy controls (n = 56), children/adolescents at increased familial risk of developing schizophrenia (n = 24) or mood disorders (n = 33), and children/adolescents without this risk (n = 18). In this paradigm, a rubber hand (visible) and a participant’s real hand (invisible) were stroked synchronously and asynchronously; we then measured subjective illusory experiences and proprioceptive drift.
Results: All groups showed the expected effect of the rubber hand illusion: stronger proprioceptive drift and increased subjective illusory experiences after synchronous versus asynchronous stroking. The effect of synchronicity on subjective experiences was significantly weaker in patients with schizophrenia than in healthy controls, and subjective ratings were positively correlated with delusions in patients. We found no significant differences between children/adolescents with and without increased familial risk.
Limitations: Large individual differences raised questions for future research.
Conclusion: We found subtle disturbances in body-ownership experiences in patients with schizophrenia, which were associated with delusions. We found no evidence for impairments in children/adolescents at increased familial risk of developing schizophrenia or a mood disorder. Longitudinal data might reveal whether impairments in body ownership are predictive of psychosis onset.
Submitted Mar. 27, 2018; Revised Jun. 12, 2018; Accepted Aug. 2, 2018; Published online Dec. 7, 2018
Affiliations: From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn).
Competing interests: M. Hillegers reports grants from the Brain and Behavior Foundation (NARSAD) during the conduct of the study. N. van Haren reports grants from the Netherlands Organization for Scientific Research during the conduct of the study and personal fees from Janssen-Cilag outside the submitted work. No other competing interests declared.
Contributors: M. Prikken, A. van der Weiden, M. Hillegers, H. Aarts and H. van Haren designed the study. M. Prikken, A. van der Weiden and H. Baalbergen acquired the data, which M. Prikken, A. van der Weiden, R. Khan, H. Aarts and N. van Haren analyzed. M. Prikken wrote the article, which all authors reviewed. All authors approved the final version to be published and can certify that no other individuals not listed as authors have made substantial contributions to the paper.
Correspondence to: M. Prikken, Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, Netherlands; email@example.com