Drift and ownership toward a distant virtual body.

Area of Science:

• Neuroscience
• Psychology
• Human-Computer Interaction

Background:

• Body ownership illusions involve participants feeling a connection to a virtual body (VB).
• Previous research suggested ownership is possible with synchronous visual and tactile stimuli, but this was debated.
• The dispute centered on whether results reflected self-recognition or true somatic body ownership.

Purpose of the Study:

• To investigate the role of visuotactile synchrony in establishing body ownership over a VB.
• To differentiate between self-recognition and somatic ownership in body ownership illusions.
• To examine physiological and behavioral responses to a threat in the context of body ownership.

Main Methods:

• Thirty participants experienced real-time VB movement synchronized with their own upper body motion.
• Participants received tactile stimulation on their back, either synchronous or asynchronous with visual stimuli on the VB.
• A threat (descending fan) was introduced, and physiological (heart rate deceleration) and behavioral (head movement) responses were recorded.

Main Results:

• Referral of touch to the VB was significantly greater in the synchronous condition.
• No other significant differences were found between synchronous and asynchronous groups initially.
• In the synchronous group, physiological responses (HRD, head movement) correlated with perceived drift illusions (forward/backward).

Conclusions:

• Visuotactile synchrony enhances the referral of touch, supporting its role in body ownership illusions.
• The brain may generate drift illusions to resolve the conflict of somatic feelings with a distant body.
• Body ownership contributes to these illusions, suggesting a complex interplay between perception and embodiment.