Interoception and Empathy Impact Perspective Taking

Adopting the perspective of another person is an important aspect of social cognition and has been shown to depend on multisensory signals from one's own body. Recent work suggests that interoceptive signals not only contribute to own-body perception and self-consciousness, but also to empathy. Here we investigated if social cognition - in particular adopting the perspective of another person - can be altered by a systematic manipulation of interoceptive cues and further, if this effect depends on empathic ability. The own-body transformation task (OBT) - wherein participants are instructed to imagine taking the perspective and position of a virtual body presented on a computer screen - offers an effective way to measure reaction time differences linked to the mental effort of taking an other's perspective. Here, we adapted the OBT with the flashing of a silhouette surrounding the virtual body, either synchronously or asynchronously with the timing of participants' heartbeats. We evaluated the impact of this cardio-visual synchrony on reaction times and accuracy rates in the OBT. Empathy was assessed with the empathy quotient (EQ) questionnaire. Based on previous work using the cardio-visual paradigm, we predicted that synchronous (vs. asynchronous) cardio-visual stimulation would increase self-identification with the virtual body and facilitate participants' ability to adopt the virtual body's perspective, thereby enhancing performance on the task, particularly in participants with higher empathy scores. We report that participants with high empathy showed significantly better performance during the OBT task during synchronous versus asynchronous cardio-visual stimulation. Moreover, we found a significant positive correlation between empathic ability and the synchrony effect (the difference in reaction times between the asynchronous and synchronous conditions). We conclude that synchronous cardio-visual stimulation between the participant's body and a virtual body during an OBT task makes it easier to adopt the virtual body's perspective, presumably based on multisensory integration processes. However, this effect depended on empathic ability, suggesting that empathy, interoception and social perspective taking are inherently linked.

Right insular damage decreases heartbeat awareness and alters cardio-visual effects on bodily self-consciousness

Javier Bello Ruiz, Olaf Blanke, Bruno Herbelin, Marta Lukowska, Roberta Ronchi

Recent evidence suggests that multisensory integration of bodily signals involving exteroceptive or interoceptive information modulates bodily aspects of self-consciousness such as self-identification and self-location. In the so-called full body illusion subjects watch a virtual body being stroked while they perceive tactile stimulation on their own body inducing illusory self-identification with the virtual body and a change in self-location towards the virtual body. In a related illusion, it has recently been shown that similar changes in self-identification and self-location can be observed when an interoceptive signal is used in association with visual stimulation of the virtual body (i.e., participants observe a virtual body illuminated in synchrony with their heartbeat). Although brain imaging and neuropsychological evidence suggest that the insular cortex is a core region for interoceptive processing (such as cardiac perception and awareness) as well as for self-consciousness, it is currently not known whether the insula mediates cardio-visual modulation of self-consciousness. Here we tested the involvement of insular cortex in heartbeat awareness and cardio-visual manipulation of bodily self-consciousness in a patient before and after resection of a selective right neoplastic insular lesion. Cardio-visual stimulation induced an enhanced alteration of bodily self-consciousness; in addition, cardio-visual manipulation was associated with an experienced loss of the spatial unity of the self (illusory bi-location and duplication of his body), not observed in healthy subjects. Heartbeat awareness was found to decrease after insular resection. Based on these data we propose that the insula mediates interoceptive awareness as well as cardio-visual effects on bodily self-consciousness and that insular processing of interoceptive signals is an important mechanism for the experienced unity of the self.

Pergamon-Elsevier Science Ltd2015

Embodiment Sensitivity to Movement Distortion and Perspective Taking in Virtual Reality

Henrique Galvan Debarba

Despite recent technological improvements of immersive technologies, Virtual Reality suffers from severe intrinsic limitations, in particular the immateriality of the visible 3D environment. Typically, any simulation and manipulation in a cluttered environment would ideally require providing feedback of collisions to every body parts (arms, legs, trunk, etc.) and not only to the hands as has been originally explored with haptic feedback. This thesis addresses these limitations by relying on a cross modal perception and cognitive approach instead of haptic or force feedback. We base our design on scientific knowledge of bodily self-consciousness and embodiment. It is known that the instantaneous experience of embodiment emerges from the coherent multisensory integration of bodily signals taking place in the brain, and that altering this mechanism can temporarily change how one perceives properties of their own body. This mechanism is at stake during a VR simulation, and this thesis explores the new venues of interaction design based on these fundamental scientific findings about the embodied self. In particular, we explore the use of third person perspective (3PP) instead of permanently offering the traditional first person perspective (1PP), and we manipulate the user-avatar motor mapping to achieve a broader range of interactions while maintaining embodiment. We are guided by two principles, to explore the extent to which we can enhance VR interaction through the manipulation of bodily aspects, and to identify the extent to which a given manipulation affects the embodiment of a virtual body. Our results provide new evidence supporting strong embodiment of a virtual body even when viewed from 3PP, and in particular that voluntarily alternating point of view between 1PP and 3PP is not detrimental to the experience of ownership over the virtual body. Moreover, detailed analysis of movement quality show highly similar reaching behavior in both perspective conditions, and only obvious advantages or disadvantages of each perspective depending on the situation (e.g. occlusion of target by the body in 3PP, limited field of view in 1PP). We also show that subjects are insensitive to visuo-proprioceptive movement distortions when the nature of the distortion was not made explicit, and that subjects are biased toward self-attributing distorted movements that make the task easier.

EPFL2017

Embodiment Sensitivity to Movement Distortion and Perspective Taking in Virtual Reality

Henrique Galvan Debarba

EPFL2017

Right insular damage decreases heartbeat awareness and alters cardio-visual effects on bodily self-consciousness

Javier Bello Ruiz, Olaf Blanke, Bruno Herbelin, Marta Lukowska, Roberta Ronchi

Pergamon-Elsevier Science Ltd2015