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

Area of Science:

• Neuroscience
• Psychology
• Human-Computer Interaction

Background:

• Self-consciousness relies on integrating multisensory bodily signals.
• Full-body illusion (FBI) experiments manipulate multisensory conflict to alter bodily self-consciousness (BSC).
• Key aspects of BSC include self-identification, self-location, and first-person perspective (1PP).

Purpose of the Study:

• To investigate how different visuospatial viewpoints affect the full-body illusion (FBI).
• To determine the impact of visuospatial viewpoint on self-identification, self-location, and 1PP within FBIs.
• To compare the effects of viewpoint manipulations when viewing a virtual body versus a non-body object.

Main Methods:

• Adapted a robotic visuotactile stroking protocol for FBI experiments.
• Participants viewed a virtual body from different posterior viewpoints using a head-mounted display.
• Control conditions included viewing a non-body object and asynchronous/synchronous visuotactile stroking.

Main Results:

• Visuospatial viewpoint significantly modulated subjective 1PP ratings when a virtual body was present, but not with a non-body object.
• Self-identification was unaffected by viewpoint but influenced by the viewed object and visuotactile synchrony.
• Self-location was dependent on both visuospatial viewpoint and visuotactile synchrony.

Conclusions:

• The visuospatial viewpoint during FBIs is a critical factor in modulating the subjective 1PP.
• Viewpoint manipulations contribute to understanding the spatial aspects of bodily self-consciousness.
• This research underscores the multisensory nature of BSC and 1PP, with implications for virtual reality and neuroscience.