The vagus nerve as a gateway to body ownership: taVNS reduces
susceptibility to a virtual version of the cardiac and tactile rubber
hand illusion
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) has been shown
to influence cognitive and emotional function and enhance interoceptive
awareness. This study investigates if taVNS effects extend to the
experience of body ownership, as measured via susceptibility to the
rubber hand illusion (RHI) in a virtual reality setting. The experiment
involved 27 participants who underwent real and sham stimulation in two
separate sessions while experiencing synchronous or asynchronous
visuo-cardiac and visuo-tactile feedback on a virtual arm in place of
their own. Results indicated that active compared to sham taVNS
decreased sensitivity to the illusion in both cardiac and tactile
trials, suggesting that the stimulation might enhance body ownership,
making individuals more attuned to their real bodily signals and less
susceptible to bodily illusions. Additionally, physiological measures
such as heart rate (HR), heart rate variability (HRV), and skin
sympathetic nervous activity (SKNA) were assessed to explore the
autonomic effects of taVNS. The findings contribute to the understanding
of the vagus nerve’s role in integrating visceral and somatosensory
signals, with implications for clinical applications in conditions
characterized by altered interoception and body ownership.