Visuospatial viewpoint manipulation during full-body illusion modulates subjective first-person perspective

Abstract

viewpoint had no effect on self-identification, but depended on the viewed object and visuotactile synchrony. Selflocation depended on visuospatial viewpoint (first experiment) and visuotactile synchrony (second experiment). Our results show that the visuospatial viewpoint from which the virtual body is seen during FBIs modulates the subjective 1PP and that such viewpoint manipulations contribute to spatial aspects of BSC. We compare the present data with recent data revealing vestibular contributions to the subjective 1PP and discuss the multisensory nature of BSC and the subjective 1PP.

Viewing one’s body during encoding boosts episodic memory

“…Finally, based on these data we argue that the brain mechanisms of BSC are linked to those of autonoetic consciousness that are of fundamental relevance to EAM. Autonoetic consciousness is the ability to mentally travel back in subjective time and recollect one's previous experiences 2, [18][19][20] and the present data suggest that multisensory bodily processing during encoding and remembering are not only of relevance for the conscious bodily experiences of self-identification, self-location, and first-person perspective 37,36,39,[44][45][46][47] , but also autonoetic consciousness.…”

“…This novel theoretical and experimental approach is based on behavioral 36,37 , neuroimaging [38][39][40] and clinical data 39,41 and involves the processing and integration of different bodily stimuli to the sense of self: bodily self-consciousness (BSC); for review see 42,43 . BSC includes conscious experiences such as self-identification and self-location 37,36,44,45 , as well as the firstperson perspective 39,46,47 . This work was based on clinical observations in neurological patients with so-called out-of-body experiences characterized by changes in the sense of self, in particular of the experienced self-location and perspective from an embodied first-person perspective to a third-person perspective 39,41 and has been able to induce milder, but comparable, states in healthy subjects using virtual reality (VR) technology to provide multisensory stimulation 36,39,47 .…”

Vestibular modulation of peripersonal space boundaries

“…Indeed, PPS appears to index the experienced position of the bodily self, as compared to the actual position of a person's body (Noel et al ., ; Salomon et al ., ). Self‐location, as indexed via PPS or other measures (e.g., Pfeiffer et al ., , ), is one important component of bodily self‐consciousness (Blanke & Metzinger, ). Another cornerstone of bodily self‐consciousness is the first‐person perspective, that is, a conscious experience of facing the world from a given, embodied location and with a give direction, which is thought to depend on multisensory‐vestibular information [(Ionta et al ., ; Pfeiffer et al ., , ), see (Pfeiffer et al ., ) for a review].…”

“…Self‐location, as indexed via PPS or other measures (e.g., Pfeiffer et al ., , ), is one important component of bodily self‐consciousness (Blanke & Metzinger, ). Another cornerstone of bodily self‐consciousness is the first‐person perspective, that is, a conscious experience of facing the world from a given, embodied location and with a give direction, which is thought to depend on multisensory‐vestibular information [(Ionta et al ., ; Pfeiffer et al ., , ), see (Pfeiffer et al ., ) for a review]. Hence, the demonstration that PPS representation, the space of the bodily self (Noel et al ., ) is molded by an array of sensory modalities including the vestibular system, may represent an important avenue of confluence between the study of self‐location and first‐person perspective (Blanke, ; Pfeiffer et al ., ; Blanke et al ., ; Pfeiffer, ).…”

Multisensory Integration in Self Motion Perception

“…-Insert Figure 5 about here -Multisensory integration and mandatory fusion of visual and vestibular cues as well as vestibulartactile interactions are largely driven by the functional necessity for accurate self-motion perception, gaze stabilisation and balance maintenance (Mergner and Rosemeier, 1998;Wexler et al, 2001). Next to self-motion perception, these processes are also important for the perception of one's body in space allowing self-identification with one's body, as well as the construction of a first-person perspective (Ionta et al, 2011;Pfeiffer et al, 2013;Pfeiffer et al, 2014), and are subtended by an anatomical pathway combining visual, vestibular and tactile information already at the level of the brainstem and the thalamus up to the cortex (Lopez and Blanke, 2011). Our work opens an avenue for a more controlled and systematic study of vestibular effects on perception, cognition, and self-consciousness.…”