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. Specifically, a greater proprioceptive drift difference (PDD) toward the rubber hand was observed for synchronous compared to asynchronous trials only during sham (t(26) = −4.58, pbonf < 0.001) but not during active (pbonf = 1.00) stimulation. A similar pattern was also observed for subjective ownership, where synchronous trials led to greater subjective ownership than asynchronous trials only during sham (t(26) = −3.52, pbonf = 0.010) but not during active (pbonf = 1.00) stimulation. These findings suggest that 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. We observed a decrease in HR during active stimulation (t(26) = 4.30, pbonf < 0.001), and an increase in SKNA during both sham (t(26) = −4.40, pbonf < 0.001) and active stimulation (t(26) = −4.85, pbonf < 0.002). These 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.

Bodily organs such as the heart and the lungs play a crucial role in maintaining physiological homeostasis in a continuous closed-loop interaction with the brain. Beyond their vital role, recent developments have emphasized the remarkable contribution of bodily signals to high-level brain functions. A direct route by which bodily signals influence brain functioning is via modulation of electrophysiological dynamics, which in turn influences the integration and processing of emotional and self-related information regulating our conscious experience. Drawing on electrophysiological investigations, we provide a comprehensive picture of the electrophysiology of interoception and its contribution to emotion, self and bodily consciousness, with a focus on cardiac, respiratory and gastric interoception. We provide evidence that altered neurophysiological responses in interoception might underlie deficits in psychopathology. We also summarize the limited evidence on the development of the electrophysiology of interoception during infancy and adolescence, as well as describing some attempts to investigate causality in the neural mechanisms underpinning interoception. A number of important areas for further research are highlighted.

l model based on synthetic data generation of electroencephalography and electrocardiography signals. Our findings show that sympathovagal activity plays a leading and causal role in initiating the emotional response, in which ascending modulations from vagal activity precede neural dynamics and correlate to the reported level of arousal. The subsequent dynamic interplay observed between the central and autonomic nervous systems sustains the processing of emotional arousal. These findings should be particularly revealing for the psychophysiology and neuroscience of emotions. “What Is an Emotion?” by William James ( 1 ), published more than a century ago, started the scientific debate on the nature of emotions. However, a shared and definitive theory of emotions is not in place yet, and the very definition of emotions and their nature is still a matter of debate. While more “classical” theories point to emotions as “the functional states of the brain that provide causal explanations of certain complex behaviors—like evading a predator or attacking prey” ( 2 ), other theories suggest how they are constructions of the world, not reactions to it ( 3 ). Namely, emotions are internal states constructed on the basis of previous experiences as predictive schemes to react to external stimuli. The role of bodily activity in emotions is often questioned. Despite the vast literature showing bodily correlates with emotions, a long-lasting debate about the relationship between bodily states and emotions persists ( 4 ). For instance, a feeling is defined as the subjective metarepresentation and labeling of physiological changes (such as an increase in heart rate, the increase of blood pressure, or changes in peristalsis) ( 5 ) that are strictly related to the body state on the one hand and to emotions on the other. To this extent, emotions are complex psychological phenomena in which feelings are interpreted and labeled. In a particular psychopathological condition known as alexit

indicate that muscle activ- ity plays a causal role in the subjective experience of emotion. But for the most … something that happens as a result of the subjective experience of an emotion; that is, it is not merely … Inner processes such as cognition and the subjective experience of emo- tion moved closer to the pale of