Modulation of Bodily Self-Consciousness by Self and External Touch

IEEE Trans Haptics. 2021 Jul-Sep;14(3):615-625. doi: 10.1109/TOH.2021.3067651. Epub 2021 Sep 9.

Abstract

The full body illusion (FBI) is a bodily illusion based on the application of multisensory conflicts that induce changes in bodily self-consciousness (BSC). This has been used to study cognitive brain mechanisms underlying body ownership and related aspects of self-consciousness. Typically, such paradigms employ external passive multisensory stimulation, thus neglecting the possible contributions of self-generated action and haptic cues to body ownership. In this article, the effects of both external and voluntary self-touch on BSC were examined with a robotics-based FBI paradigm. We compared the effects of classical passive visuotactile stimulation and active self-touch (in which experimental participants had a sense of agency over the tactile stimulation) on the FBI. We evaluated these effects using a questionnaire, crossmodal congruency task, and measurements of changes in self-location. The results indicated that both synchronous passive visuotactile stimulation and synchronous active self-touch induced illusory ownership over a virtual body, without significant differences in their magnitudes. However, the FBI induced by active self-touch was associated with a larger drift in self-location towards the virtual body. These results show that movement-related signals arising from self-touch impact the BSC not only for hand ownership but also for torso-centered body ownership and related aspects of BSC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Image
  • Consciousness
  • Humans
  • Illusions*
  • Self Concept
  • Touch
  • Touch Perception*
  • Visual Perception