Multisensory integration across exteroceptive and interoceptive domains modulates self-experience in the rubber-hand illusion

Identifying with a body is central to being a conscious self. The now classic “rubber hand illusion” demonstrates that the experience of body ownership can be modulated by manipulating the timing of exteroceptive(visual and tactile)body-related feedback. Moreover,the strength of this modulation is related to individual differences in sensitivity to internal bodily signals(interoception). However the interaction of exteroceptive and interoceptive signals in determining the experience of body-ownership within an individual remains poorly understood.Here, we demonstrate that this depends on the online integration of exteroceptive and interoceptive signals by implementing an innovative “cardiac rubber hand illusion” that combined computer-generated augmented-reality with feedback of interoceptive (cardiac) information. We show that both subjective and objective measures of virtual-hand ownership are enhanced by cardio-visual feedback in-time with the actual heartbeat,as compared to asynchronous feedback. We further show that these measures correlate with individual differences in interoceptive sensitivity,and are also modulated by the integration of proprioceptive signals instantiated using real-time visual remapping of finger movements to the virtual hand.Our results demonstrate that interoceptive signals directly influence the experience of body ownership via multisensory integration,and they lend support to models of conscious selfhood based on interoceptive predictive coding

It Feels Like It's Me:Interpersonal Multisensory Stimulation Enhances Visual Remapping of Touch From Other to Self

Abstract Understanding other people's feelings in social interactions depends on the ability to map onto our body the sensory experiences we observed on other people's bodies. It has been shown that the perception of tactile stimuli on the face is improved when concurrently viewing a face being touched. This Visual Remapping of Touch (VRT) is enhanced the more similar others are perceived to be to the self and is strongest when viewing one's face. Here, we ask whether altering self-other boundaries can in turn change the VRT effect. We used the enfacement illusion, which relies on synchronous interpersonal multisensory stimulation (IMS), to manipulate self-other boundaries. Following synchronous, but not asynchronous, IMS, the self-related enhancement of the VRT extended to the other individual. These findings suggest that shared multisensory experiences represent one key way to overcome the boundaries between self and others, as evidenced by changes in somatosensory processing of tactile stimuli on one's own face when concurrently viewing another person's face being touched

Embodying the Other: Effects of Experiencing the Rubber Hand Illusion in Virtual Reality on Implicit Racial Biases

Research on the Rubber Hand Illusion (RHI) has recently begun to explore induced body ownership exercises as a means for experimentally changing implicit social attitudes. Similarly, recent innovations in Virtual Reality (VR) have lead researchers to begin investigating VR as a tool for empathy training and perspective taking. The present study addresses these two fields of research by replicating the RHI in VR, with the goal of inducing body ownership over virtual hands of racial outgroups. A race Implicit Association Test was administered to measure racial biases before and after the illusion. It was predicted that participants who experienced the illusion with the virtual hand of a race different than their own would show greater changes in performance on the post-illusion Implicit Association Test. By and large, results did not show a significant difference between the different hand conditions, though there was a marginally significant effect of racial membership on the strength of ownership during the illusion. Future research should focus on assessing pre-existing implicit attitudes, in order to clarify the question concerning which types of people benefit the most from these body ownership exercises that aim to change social biases

More than skin deep: body representation beyond primary somatosensory cortex

The neural circuits underlying initial sensory processing of somatic information are relatively well understood. In contrast, the processes that go beyond primary somatosensation to create more abstract representations related to the body are less clear. In this review, we focus on two classes of higher-order processing beyond somatosensation. Somatoperception refers to the process of perceiving the body itself, and particularly of ensuring somatic perceptual constancy. We review three key elements of somatoperception: (a) remapping information from the body surface into an egocentric reference frame (b) exteroceptive perception of objects in the external world through their contact with the body and (c) interoceptive percepts about the nature and state of the body itself. Somatorepresentation, in contrast, refers to the essentially cognitive process of constructing semantic knowledge and attitudes about the body, including: (d) lexical-semantic knowledge about bodies generally and one’s own body specifically, (e) configural knowledge about the structure of bodies, (f) emotions and attitudes directed towards one’s own body, and (g) the link between physical body and psychological self. We review a wide range of neuropsychological, neuroimaging and neurophysiological data to explore the dissociation between these different aspects of higher somatosensory function

The neuroscience of body memory: Recent findings and conceptual advances

The body is a very special object, as it corresponds to the physical component of the self and it is the medium through which we interact with the world. Our body awareness includes the mental representation of the body that happens to be our own, and traditionally has been defined in terms of body schema and body image. Starting from the distinction between these two types of representations, the present paper tries to reconcile the literature around body representations under the common framework of body memory. The body memory develops ontogenetically from birth and across all the life span and is directly linked to the development of the self. Therefore, our sense of self and identity is fundamentally based on multisensory knowledge accumulated in body memory, so that the sensations collected by our body, stored as implicit memory, can unfold in the future, under suitable circumstances. Indeed, these sets of bodily information had been proposed as possible key factors underpinning several mental health illnesses. Following this perspective, the Embodied Medicine approach put forward the use of advanced technologies to alter the dysfunctional body memory to enhance people’s well-being. In the last sections, recent experimental pieces of evidence will be illustrated that targeted specifically bodily information for increasing health and wellbeing, by means of two strategies: interoceptive feedback and bodily illusions

Changing bodies changes minds:owning another body affects social cognition

Research on stereotypes demonstrates how existing prejudice affects the way we process outgroups. Recent studies have considered whether it is possible to change our implicit social bias by experimentally changing the relationship between the self and outgroups. In a number of experimental studies, participants have been exposed to bodily illusions that induced ownership over a body different to their own with respect to gender, age, or race. Ownership of an outgroup body has been found to be associated with a significant reduction in implicit biases against that outgroup. We propose that these changes occur via a process of self association that first takes place in the physical, bodily domain as an increase in perceived physical similarity between self and outgroup member. This self association then extends to the conceptual domain, leading to a generalization of positive self-like associations to the outgroup

Mindfulness-based meditation, interoceptive awareness and heart rate variability

La tesi di dottorato dal titolo “Mindfulness based meditation, Interoceptive awareness and Heart rate variability (tutor: prof. Antonino Raffone; cotutor: prof.ssa Maria Casagrande) affronta la relazione tra l'esperienza del corpo che si svolge sia esplicitamente, limitata alla sua dimensione più sottile e cioè la consapevolezza interocettiva, che implicitamente nel corso dell'esperienza emotiva, e la variabilità della frequenza cardiaca intesa come indicatore di adattamento all'ambiente e di regolazione emotiva, eventualmente modulate dalla meditazione di consapevolezza declinata in diversi contesti. Dopo un primo capitolo introduttivo in cui descrivo per sommi capi l’evoluzione nel tempo degli studi sulla meditazione, nei primi capitoli vengono definiti ed approfonditi gli elementi oggetto di studio. Il secondo capitolo è perciò dedicato alla meditazione mindfulness, alle sue origini buddhiste ed alle sue misure, le sue diverse declinazioni sia nei percorsi strutturati quali MBSR e MBCT che nei più recenti approcci terapeutici di psicoterapia cognitiva di terza generazione. Il terzo capitolo è dedicato alla consapevolezza interocettiva ed alle sue misure. Il quarto capitolo alla variabilità cardiaca, inclusa la descrizione dei parametri che rendono possibile il suo studio, con un’attenzione particolare al valore di indice di regolazione emotiva mediata dal vago ed alla descrizione delle sue misure. Quindi i successivi quattro capitoli sono dedicati alla presentazione dei diversi studi fatti con due gruppi in due diversi contesti, e cioè nel corso di un percorso MBSR e di un ritiro di Insight, riportando il processo delle analisi, i risultati e le conclusioni. Infine nell’ultimo capitolo ho inserito una discussione sull’insieme del lavoro fatto, incluse le problematicità riscontrate e le possibilità di approfondimento in studi successivi

The neuroscience of body memory: From the self through the space to the others.

Abstract Our experience of the body is not direct; rather, it is mediated by perceptual information, influenced by internal information, and recalibrated through stored implicit and explicit body representation (body memory). This paper presents an overview of the current investigations related to body memory by bringing together recent studies from neuropsychology, neuroscience, and evolutionary and cognitive psychology. To do so, in the paper, I explore the origin of representations of human body to elucidate their developmental process and, in particular, their relationship with more explicit concepts of self. First, it is suggested that our bodily experience is constructed from early development through the continuous integration of sensory and cultural data from six different representations of the body, i.e., the Sentient Body (Minimal Selfhood), the Spatial Body (Self Location), the Active Body (Agency), the Personal Body (Whole Body Ownership – Me); the Objectified Body (Objectified Self – Mine), and the Social Body (Body Satisfaction – Ideal Me). Then, it is suggested that these six representations can be combined in a coherent supramodal representation, i.e. the "body matrix", through a predictive, multisensory processing activated by central, top–down, attentional processes. From an evolutionary perspective, the main goal of the body matrix is to allow the self to protect and extend its boundaries at both the homeostatic and psychological levels. From one perspective, the self extends its boundaries (peripersonal space) through the enactment and recognition of motor schemas. From another perspective, the body matrix, by defining the boundaries of the body, also defines where the self is present, i.e., in the body that is processed by the body matrix as the most likely to be its one, and in the space surrounding it. In the paper I also introduce and discuss the concept of "embodied medicine": the use of advanced technology for altering the body matrix with the goal of improving our health and well-being