Predisposition to out-of-body experience (OBE) is associated with aberrations in multisensory integration: Psychophysiological support from a "rubber hand illusion" study.

People who have spontaneous out-of-body experiences in everyday life show differences in how their brains integrate sensory information. In a rubber hand illusion experiment with 180 participants, those prone to out-of-body experiences did not show the typical fear response to a threat directed at the rubber hand when the brushing was asynchronous, unlike control participants who reacted more strongly during synchronous stimulation. This suggests that imprecise top-down tuning in multisensory integration, possibly through predictive coding mechanisms, may underlie aberrant self-consciousness even in nonclinical populations.

Study at a glance

Abstract

It has been argued that disorders in body-ownership and aberrant experiences in self-consciousness are due to biases in multisensory integration. Here we examine whether such biases are also associated with spontaneous out-of-body experiences (OBEs) in a nonclinical population. One-hundred and 80 participants took part in a rubber hand illusion (RHI) experiment with synchronous and asynchronous visual and tactile stimulation. A realistic threat was delivered to the rubber hand after a fixed period of stimulation. Self-report exit questionnaires measured the subjective strength of the illusion and psychophysiological measures (skin conductance responses/finger temperature) provided an objective index of fear/anxiety toward the threat. Control participants reported a stronger RHI, and revealed larger threat-related skin conductance responses during synchronous compared with asynchronous brushing. For participants predisposed to OBEs, the magnitude of the skin conductance was not influenced by brushing synchrony-fear responses were just as strong in the asynchronous condition as they were in the synchronous condition. There were also no reliable effects of finger temperature for either group. Collectively, these findings are taken as support for the presence of particular biases in multisensory integration (perhaps via predictive coding mechanisms) in which imprecise top-down tuning occurs resulting in aberrant experiences in self-consciousness even in nonclinical hallucinators. (PsycINFO Database Record