Evaluation of self-disturbance in patients with schizophrenia using the rubber hand illusion technique

Abstract

In cognitive science, self-disturbance in schizophrenia is regarded as an unusual sense of body ownership. This study examined the possibility of discriminating self-disturbance between patients with schizophrenia and healthy individuals using the rubber hand illusion (RHI). We evaluated RHI in inpatients with schizophrenia with mainly negative symptoms (« = 26) and normal control subjects (>? =10). The group with schizophrenia had a significantly higher score than the control group on only the following item: "It seemed as if I might have an extra left hand," suggesting that patients with schizophrenia have strong self-disturbance. This mdicates that it is difficult for them to have an appropriate sense of body ownerslup and normal reality testmg. The RHI evaluation might be useful as an assessment tool for schizophrenia since it is easy to use for evaluating self-disturbance, even when not recognized by patients with schizophrenia themselves. This study supports the usefulness of the RHI evaluation as a tool for assessmg self-disturbance m patients with schizophrenia.